[v12-engine] Weird ignition problem - v12 6.0L

V12-Engine
21

In reply to a message from George Balthrop sent Sat 3 Nov 2012:

George, Bob, Dave and others who have followed along.
7 hours after I took the video of the sparks from the coil,
I went back to the garage, opened the door, turned the key
and it fired right away.
This would be the first time since September when the engine
came to life upon 1-2 seconds of cranking.

Temperature in the garage – 60 F
Will there be unburned fuel in the cylinders from the
earlier test, probably not, the fact is I have not touched
anything else.

This morning I tested the resistance of my flywheel sensor,
the crankshaft sensor and the new one I have already gotten.
They all measured 670-680 Ohms.

I inspected the flywheel sensor – it was a bit oily but no
cracks and other debris, cleaned and reinstalled.

Where does this leave us?

Thanks,
Steve–
The original message included these comments:

Sorry for the fire drill. When I asked of the CTS you had checked
resistance on was the one on the B Bank (EFI), I didn’t realize that
your 95 didn’t have the A bank CTS for the Marelli ignition that the
5.3L Marelli cars had. It appears that no 6.0L car had the A bank CTS,
but rather used an Air Temperature Sensor for the Marelli digital
ignition.
In any event, I would doubt that ANY temperature sensor has anything to
do with your delayed cold start problem.
George Balthrop, Clifton, VA USA

–
'95 XJS V12 6.0L, saphire/tan
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22

In reply to a message from sbobev sent Sun 4 Nov 2012:

The main thing you have now cleaned the sensor which relates to
FF77 and so now you just need to make sure it is all running ok and
then you just need to wait for a few days for you to be able to
test it . I still think it could have had fuel in the cylinders as
i nhave had a flooded car that would not start in the next morning
in colder weather. The flywheel to sensor gap needs to be correct
and any dirt / oil between them will not help .

I would take it for a short drive to worm it up if you can and then
just let it stand for a few days and lets us know what it does .–
95 XJR6, 94 XJS 6.0 coupe, 04 XK8 ,99 Ka
Croydon , SURREY, United Kingdom
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23

Hi Steve,

If the car started normally for the first time, and NO parts were
changed since the last time it took 7 to 10 seconds to fire, then it is
likely that the problem was caused by a bad, loose or dirty connection.
Of course it may be an intermittent problem which will recur.

Please think back carefully an list any connector that was
disconnected, reconnected, cleaned, etc. in that interval between last
long crank and the fast/proper start.

You mention disconnecting the two coil king leads from the top of the
distributor cap to run the spark test. In that test did you
IMMEDIATELY, when cranking of the starter first began, get a strong,
blue spark from EACH coil wire to ground, and did that spark continue
to look the same at all times as the starter cranked?

Was that test BEFORE you disconnected anything else, such as the
flywheel sensor connector or the crankshaft sensor connector (to
measure resistance)?

Did you separate either the flywheel sensor connector or the crankshaft
position sensor connector BEFORE you started the engine and it fired
immediately?

Did you clean any of the connectors, or find any evidence of corrosion,
rust, etc. on the pins or sockets?

Knowing the sequence of the events described above would allow a better
guess as to where the problem was located, but it appears that it was a
corroded, loose or dirty connector which has been at least temporarily
corrected.

George Balthrop, Clifton, VA USA
89 and 85 XJ-S Coupes; 89 XJ40 VDP-----Original Message-----
From: sbobev shelxtl@yahoo.com

7 hours after I took the video of the sparks from the coil,
I went back to the garage, opened the door, turned the key
and it fired right away.

This would be the first time since September when the engine
came to life upon 1-2 seconds of cranking.

This morning I tested the resistance of my flywheel sensor,
the crankshaft sensor and the new one I have already gotten.
They all measured 670-680 Ohms.

I inspected the flywheel sensor – it was a bit oily but no
cracks and other debris, cleaned and reinstalled.

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24

In reply to a message from George Balthrop sent Sun 4 Nov 2012:

Hello George:

Prior to this development on Saturday night, nothing, I mean
NOTHING was connected/reconnected/cleaned, but the two leads
from the coils.
The test (link to the video is above) clearly shows that
both coils give strong spark immediately upon cranking. Did
you see it?

There was a 7 hour period between this spark-test and the
successful startup – NOTHING was
connected/reconnected/cleaned – I was out with my wife and
the kids. The hypothesis for ‘‘fix’’ due to a bad connector
does not seem possible.

The flywheel sensor was resistance-tested on the next day
and I have not done anything else. All connectors looked
very good and aside from some engine oil on the flywheel
sensor, there was nothing abnormal that I could see.

All further tests will have to wait until the next weekend,
I am afraid. Given all the feedback, the flywheel sensor
and a possible fueling issue (recall – car does not run
poorly cold/warm, just requires long crank), I cannot think
of anything else.

One earlier observation we have not addressed, which still
bothers me is the fact that 2-3 weeks ago, when I was
testing all vacuum connections, I tested the vacuum tube to
the EFI ECU in the boot and forgot to re-attach it. It was
not a start from cold, but the engine fired and run normal
(slightly higher RMPs because it was breathing through the
tube, but not codes and no obvious signs of troubles).

I’d like to get an affirmative answer from someone else with
a Marelli car – is it possible for the engine to start/run
with the vacuum tube to the EFI ECU in the boot
disconnected?

If this is NOT possible, then I(we) know that the EFI ECU is
misbehaving.

Thanks for all responses,
Steve–
The original message included these comments:

If the car started normally for the first time, and NO parts were
changed since the last time it took 7 to 10 seconds to fire, then it is
likely that the problem was caused by a bad, loose or dirty connection.
Of course it may be an intermittent problem which will recur.
Please think back carefully an list any connector that was
disconnected, reconnected, cleaned, etc. in that interval between last
long crank and the fast/proper start.
You mention disconnecting the two coil king leads from the top of the
distributor cap to run the spark test. In that test did you
IMMEDIATELY, when cranking of the starter first began, get a strong,
blue spark from EACH coil wire to ground, and did that spark continue

–
'95 XJS V12 6.0L, saphire/tan
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25

Hi Steve,

Actually, removing the two coil king leads, testing spark and then
re-inserting the king leads into the distributor cap IS disconnecting
and reconnecting those TWO connectors. In fact, if you have an
ignition fault, one of the first things one should try (since it is so
quick and easy) is to twist and push ALL the HT wire connectors on top
of the cap and at the coils.

My Lucas CEI 89 shutdown during operation one day (only time it has
ever quit on me), and in less than a minute I had it running again
(with no problems since) simply by performing that procedure. In my
case it was probably a loose HT lead connection where the king lead
attaches to the coil, as opposed to the other end where you
disconnected from the distributor cap, but the same principle applies.

The facts that (1) you instantly got a good spark from each coil king
lead when you cranked the starter during the test, and also (2) the car
started immediately the next time you tried to start the car after
reconnecting the king leads (even though it was ~7 hours later, but
with no other intervening event where you disconnected anything), would
suggest that a loose/corroded king lead connection at the cap MAY have
been the cause of your delayed firing on starter cranking.

The one thing that makes that theory a bit questionable to me is that
you have TWO different coil king leads, and the likelihood of BOTH
being loose or corroded is slim. Considering the fact that the engine
should start and run on just ONE bank further casts doubt on that
theory. However, when you DID have the problem, the engine did
ultimately start after 7 to 10 seconds of starter cranking, so perhaps
loose or corroded king lead(s) WAS the problem.

In that scenario, you have a WEAK spark from one coil during cranking
due to a loose or corroded HT connection, but once the engine starts
and the alternator output increases system voltage, the spark improves
and the engine performs normally. Is that actually what happened? No
one can say for sure – just start it/drive it as often as possible
and see if the problem returns :wink:

MAP VAC LINE DISCONNECTED FROM EFI ECU:

Did you drive the car with the vacuum line disconnected, or just run
the engine at idle with increased idle speed due to vacuum leak?

Although there may be a reason why the MAP sensor function in the 6.0L
with Marelli is different than that in the 5.3L Lucas ignition, I can’t
think of one immediately. I know that with the 5.3L Lucas system, the
engine runs very rich, usually with black smoke from the exhaust, even
at an idle. It WILL at least start with that vacuum line open.

The reason it would be expected to run rich as I understand it, is that
manifold vacuum drops when the throttle is opened, so the lack of
vacuum to the MAP sensor in the ECU causes overfueling as the ECU
“thinks” the throttle has suddenly opened and provides increased
injector pulse duration, even though the air being drawn into the
cylinders remains the same (except for the slight increase via the open
vacuum hose) as the throttle plates are NOT opened.

Of course, your 6.0L has either the 26CU or 36CU (probably the latter)
so it may function quite differently from the 6CU and 16CU with which I
am familiar, as far as the MAP sensor is concerned.

If your engine is performing normally at all levels of acceleration and
idle, I would NOT be concerned about an ECU problem.

Perhaps someone with a 6.0L similar to Steve’s can test this and let us
know?

George Balthrop, Clifton, VA USA
89 and 85 XJ-S Coupes; 89 XJ40 VDP-----Original Message-----
From: sbobev shelxtl@yahoo.com

Prior to this development on Saturday night, nothing, I mean
NOTHING was connected/reconnected/cleaned, but the two leads
from the coils.

The test (link to the video is above) clearly shows that
both coils give strong spark immediately upon cranking. Did
you see it?

There was a 7 hour period between this spark-test and the
successful startup – NOTHING was
connected/reconnected/cleaned… The hypothesis for ‘‘fix’’ due to a
bad connector
does not seem possible.

The flywheel sensor was resistance-tested on the next day
and I have not done anything else. All connectors looked
very good and aside from some engine oil on the flywheel
sensor, there was nothing abnormal that I could see…

One earlier observation we have not addressed, which still
bothers me is the fact that 2-3 weeks ago, when I was
testing all vacuum connections, I tested the vacuum tube to
the EFI ECU in the boot and forgot to re-attach it. It was
not a start from cold, but the engine fired and run normal
(slightly higher RMPs because it was breathing through the
tube, but not codes and no obvious signs of troubles).

I’d like to get an affirmative answer from someone else with
a Marelli car – is it possible for the engine to start/run
with the vacuum tube to the EFI ECU in the boot
disconnected?

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26

In reply to a message from George Balthrop sent Mon 5 Nov 2012:

Hi George:
I would not dare to disagree with you, but it this case I
had gone through everything ignition-related without any
success – before I posted. My initial message may not
clearly state it, but all ignition wires were removed and
tested for spark, I had verified the CST, firing order,
vacuum lines etc.
This did NOT change anything.

When I said NOTHING, I meant nothing after the thread begun
and after you suggested to test during cold cranking before
messing with the flywheel sensor.

BTW, I am yet to confirm that the successful start on
Saturday is reproducible.

So far we’ve got the following – last problem-free cold
ignition in early August. Passed emissions in Wilmington
Delaware on August 7. From mid-August to early September the
car is locked in the garage while I travelled abroad.

When I returned, the first FF77 appeared during a long and
painful cold start. Car re-started/run OK after that until
the next cold start. The 7-10 seconds cold-cranking was
filmed and shared with many of you.

The cold starts (6 or 7 since than) have been long until the
day before yesterday (November 3rd).

I wish I could drive it more often, but with a newborn –
well, the XJS is not exactly the car you drive you baby in.

Best regards,
Steve–
The original message included these comments:

Actually, removing the two coil king leads, testing spark and then
re-inserting the king leads into the distributor cap IS disconnecting
and reconnecting those TWO connectors. In fact, if you have an
ignition fault, one of the first things one should try (since it is so
quick and easy) is to twist and push ALL the HT wire connectors on top
of the cap and at the coils.
The facts that (1) you instantly got a good spark from each coil king
lead when you cranked the starter during the test, and also (2) the car
started immediately the next time you tried to start the car after
reconnecting the king leads (even though it was ~7 hours later, but
with no other intervening event where you disconnected anything), would

–
'95 XJS V12 6.0L, saphire/tan
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27

In reply to a message from George Balthrop sent Mon 5 Nov 2012:

George:
My EFI ECU is the 36-type.
And yes, I did drive the car back-and-forth to work (ca. 15
miles combined) before I realized the extremely stupid
mistake I’d made.

I did NOT notice any black smoke or problems running. No
codes, although the JDHT ROM says that the PCMF needs
fluctuating MAP signal, otherwise it should come with DIC
FF13.

As you perhaps saw in the video, the engine, once warmed up
can be revved above 5000 RPMs and there is no popping,
vibrations (with tube re-attached, I connected it at once as
soon as I realized it). Thus, I’d also think the ECU is not
a suspect, but what else is left?

I am sorry for the long posts, but the scientist in me
really, really needs an answer.

Best regards,
Steve–
The original message included these comments:

MAP VAC LINE DISCONNECTED FROM EFI ECU:
Did you drive the car with the vacuum line disconnected, or just run
the engine at idle with increased idle speed due to vacuum leak?
Although there may be a reason why the MAP sensor function in the 6.0L
with Marelli is different than that in the 5.3L Lucas ignition, I can’t
think of one immediately. I know that with the 5.3L Lucas system, the
engine runs very rich, usually with black smoke from the exhaust, even
at an idle. It WILL at least start with that vacuum line open.
The reason it would be expected to run rich as I understand it, is that
manifold vacuum drops when the throttle is opened, so the lack of
vacuum to the MAP sensor in the ECU causes overfueling as the ECU

–
'95 XJS V12 6.0L, saphire/tan
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28

Hi Steve,

There may never BE an ANSWER :wink:

That’s the frustrating thing about an intermittent or corroded/dirty
connection – it may cause an anomaly such as slow cold start, and then
once current starts flowing at higher voltage after startup, everything
is fine. The connection can also heat up as a result of the resistance
to current flow, and then make a better connection.

Testing when it’s running or starting as it should doesn’t provide ANY
clues in MOST such situations. If the worst it does is to start after
10 seconds of cold starter cranking, then you have a VERY small test
window. You then have to wait for hours before the anomaly occurs
again and you have another brief test window.

BTW, did you ever try shutting off the engine immediately after cold
start, and trying again in ~ 15 to 30 minutes to see if the delay
occurs then?

Sometimes the best approach is to simply take any reasonable remedial
action available, such as cleaning all possible connectors, or
inspecting/cleaning relay contacts, until the problem goes away.
Sometimes you can only be sure what the problem was when it gets worse,
and the intermittent problem becomes permanent, and the car won’t start
at all.

IIRC, (1) you never had a problem of ANY kind once the engine fired
after cold cranking, (2) you never had to crank it longer than ~ 10
seconds before it ultimately fired, and (3) you never had a slow start
if the engine had been run at least an hour prior to starting?

Also, the fact that the problem first occurred after the car had NOT
been started for over a month, is consistent with a loose, dirty or
corroded connection somewhere. That could be a CPS or Flywheel sensor
connector, the ignition switch, the splice in the ignition wire feed to
the coils and amps, or even a connection somewhere in the fuel pump
circuit. It could also include the main ECU connectors for the EFI or
the Ignition. It could be corroded contacts in the EFI Main Relay or
the Fuel Pump 1 relay. And the list goes on.

If I were in your situation, I would just try to start it and drive it
locally twice a week for ~ 5minutes each time (to reach normal
operating temp) and create a log to record any anomalies (or lack
thereof) precisely. If it takes more than 3 seconds to start, I would
repeat the coil HT spark test on starter cranking to see if you
immediately get spark when the starter first begins to crank.

If that test produces proper spark immediately, I would then apply the
ground jumper to pin 85 of Fuel Pump 1 relay to see if the relay runs
immediately upon turning the key to run position, or if it takes a few
seconds for the relay contacts to close and the pump to run. Unless I
missed something, we have NOT ruled out a bad EFI Main relay or Fuel
Pump 1 relay, where pitted contacts produce a delayed pump or delayed
EFI power-up upon cranking.

If the 36CU is like the earlier 6CU & 16CU with which I am familiar,
when you turn the key to the run position but do NOT start, the pump is
supposed to run for a second or two and then shut off. It is then
supposed to begin running again when the starter relay is engaged. On
cars with crank sensors, a signal from one of them indicating the
engine is turning may well provide the same feature.

So one thing you CAN do when it is starting correctly is to listen to
that pump and determine when it runs after turning the key to run
position, and then during starter cranking. You will then know what it
is SUPPOSED to do, and can tell if it doesn’t happen when starting is
delayed.

Any bad connection in the fuel pump circuit which delays fuel pump
operation would cause your problem, so you might try to develop a test
that meets your criteria to monitor pump operation.

One simple preventive maintenance approach would be to pull the fuel
pump 1 relay, pull the cover off, and inspect the contacts for wear.
Same for the Main Relay if the pump relay is OK.

I don’t have any magic bullet for your situation thus far. I would
just be glad it’s not that bad, NOT fear the worst, and continue to
monitor it.

Please let us know if anything changes, or of any new findings.

George Balthrop, Clifton, VA USA
89 and 85 XJ-S Coupes; 89 XJ40 VDP-----Original Message-----
From: sbobev shelxtl@yahoo.com

the scientist in me really, really needs an answer

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29

In reply to a message from George Balthrop sent Mon 5 Nov 2012:

George:
All is true. How would I know if the engine will fire
properly or not to test? :slight_smile:
On Saturday, when I did it, I was assuming the same long
cold cranking scenario, yet, I did show good spark and
started normal several hours later.

Also, the link I sent to you offlist to file MVI_1978.AVI
shows startup after I ran the engine for 5 minutes and
turned it off and waited 90 minutes. Engine had not cooled
completely, but was in C at the gauge. Started normal.

Intermittent is not the right word here, there is a clear
pattern. I will do more monitoring and will report back,
although if you are right, the dirty connection might have
cured itself for the time being.

Another possibility, which I discussed off-list with Dave
and Grant Francis is ‘‘lazy’’ fuel pump, where 2 seconds does
not allow enough fuel to prime the rail. Given the long
periods of inactivity, depressurization of the fuel lines is
quite likely, and if the pump does not work (yes, this could
also be pump relay), we’ve got the problem. However, I
tried cycling the ignition key several times to on/off for
2-3 sec to get more fuel pumped and this did NOT change
anything.

Can someone confirm that the 36CU does the same function
with the key in ON-position as the 6CU or 16CU by providing
2 seconds of fuel pumping? Dave, do you know?

As of the ground to the fuel pump relay, I sent you an email
off-list, which you may not have seen.
I looked up some of your older post and I am somewhat
unclear.
Your suggestion is to leave the relay in place and at the
base, where the brown/pink wire comes in, to connect a wire
going to a good ground point.
If this is correct, will the negative battery terminal be
OK, Should I leave the jumper there when I crank after 10
seconds?
Many thanks
Steve–
The original message included these comments:

There may never BE an ANSWER :wink:
Testing when it’s running or starting as it should doesn’t provide ANY
clues in MOST such situations. If the worst it does is to start after
10 seconds of cold starter cranking, then you have a VERY small test
window. You then have to wait for hours before the anomaly occurs
again and you have another brief test window.
BTW, did you ever try shutting off the engine immediately after cold
start, and trying again in ~ 15 to 30 minutes to see if the delay
occurs then?
IIRC, (1) you never had a problem of ANY kind once the engine fired
after cold cranking, (2) you never had to crank it longer than ~ 10

–
'95 XJS V12 6.0L, saphire/tan
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30

Hi Steve,

REASON FOR JUMPER:
What the ground jumper is supposed to do is bypass the fuel pump
circuit in the EFI ECU, so that the fuel pump runs at ALL times when
the key is in the run position, and it is NOT for constant use, just
for test purposes.

There is 12V+ to pin 86 of the relay base (one side of the
electromagnet) of the fuel pump relay at all times when the key is in
the run position. What the fuel pump circuit in the ECU does is
provide a ground to pin 85 of the relay base (the other side of the
relay electromagnet) when the pump is supposed to run, so application
of this ground makes the pump run whenever the key is in Run position.

The ECU (at least on the 6CU and 16CU with which I am familiar) is
supposed to provide a ground under the three following conditions: (1)
a “priming burst” (to achieve fuel rail pressure) for one to two
seconds when the ignition switch is first turned to the run position;
(2) during starter cranking, and (3) at any time the engine is running
and a speed signal is being generated.

What applying the ground jumper is intended to do for test purposes in
your case is to make sure the fuel pump has run long enough before
starter cranking to generate proper rail pressure (a pressure gauge at
the rail would do the same thing, but takes longer to plumb in and
costs more if you don’t already have one). You can also listen to the
pump and see if it begins to run immediately when the key is turned to
run (confirms the pump relay is working correctly).

METHODS OF APPLYING JUMPER:
You need to have the relay pins in contact with the base sockets. You
can either leave the relay fully seated in the socket and make contact
with the Pink/Brown wire below pin 85 of the relay base, or pull the
relay half-way off the base (half the length of each pin is still
inserted into the base), and put an alligator clip on the half-exposed
pin 85. Whichever method you use, make sure you do NOT contact any of
the other wires or pins with the ground wire, as all of them will be
12V+ at some point in the operation, and you will make a short and ruin
something if the ground wire contacts any other pin.

You can attach the other end of the ground jumper either to the battery
ground (-) terminal, or any bolthead or clean (unpainted) metal in the
chassis.

George Balthrop, Clifton, VA USA
89 and 85 XJ-S Coupes; 89 XJ40 VDP-----Original Message-----
From: sbobev shelxtl@yahoo.com

Your suggestion is to leave the relay in place and at the
base, where the brown/pink wire comes in, to connect a wire
going to a good ground point.
If this is correct, will the negative battery terminal be
OK, Should I leave the jumper there when I crank after 10
seconds?

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31

In reply to a message from George Balthrop sent Mon 5 Nov 2012:

Gentlemen:
I just wanted to provide an update, although, there is no
progress and perhaps George is right, there may never be an
answer.
I had two SUCCESSFUL cold startups this weekend. WITHOUT
doing anything else (in addition to what I’ve already
described).

However, I noticed something which might be a clue. The
engine was just started and cold-running, rmps were in the
1100-1200 range. Perhaps only 15-20 seconds had elapsed,
when I pressed on the accelerator and the rmps increased to
above 2000 for a second or two. All was normal up until I
removed my foot from the pedal and the engine was supposed
to return to idle.

Well, it kind of did, but the rpms dipped to may be 500 or
so and it looked like it was going to die, I stepped on the
accelerator again, and it revved. No popping, just had hard
time idling for another 15-20 seconds.

After that, all was good and it ran fine for 15 minutes in
the driveway. I drove 10 miles, all was good.

Could the the rough cold-running after the throttle was
opened (and the vacuum decreased) be an indicator that the
MAP sensor of the EFI ECU is acting up? Recall that I
reported starting/running the engine with this vacuum line
disconnected?

Does anyone know if a fully functional 36CU will allow this
to happen?

Best regards,
Steve–
The original message included these comments:

There may never BE an ANSWER :wink:
That’s the frustrating thing about an intermittent or corroded/dirty
connection – it may cause an anomaly such as slow cold start, and then
once current starts flowing at higher voltage after startup, everything
is fine. The connection can also heat up as a result of the resistance
to current flow, and then make a better connection.
Testing when it’s running or starting as it should doesn’t provide ANY
clues in MOST such situations. If the worst it does is to start after
10 seconds of cold starter cranking, then you have a VERY small test
window. You then have to wait for hours before the anomaly occurs
again and you have another brief test window.

–
'95 XJS V12 6.0L, saphire/tan
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32

Reviving this old thread of mine. The engine has been acting like possessed for the last year or so.
Sometime will be starting and running flawlessly, sometimes will start fine but then will drop fueling for the B-bank altogether.

The long cranking problem that is described in the previous posts appeared to be gone. Until recently.
I noticed a new pattern – cranking time from cold appears to correlate with the amount of fuel in the tank.

Low fuel – longer cranking
Tank full – normal cranking

ONLY from cold. No difference when warm.

With low fuel in the tank, cycling the ignition key several times (as discussed previously, to purge lines after an overnight stay) does nothing. Notice that I have installed a permanent fuel pressure gauge and I know that the pump works and pressurizes the system

Set-up:

IMG_2122
IMG_21221080×810 201 KB

Pressure:

IMG_2125
IMG_21251080×722 119 KB

The 6.0L V12 has a 3 bar FPR, but I never reach 45 psig before the engine is cranked
Once it fires, the pressure is modulated based on the manifold vacuum (this is what I have at idle):

IMG_2124
IMG_21241074×766 139 KB

I have replaced everything ignition-related. Two 36CUs, injectors cleaned not too long ago, new fuel filter.

The only two components related to fueling that have not been replaced are the FPR (NLA part) and the fuel pump(s).

In the past members suggested “lazy” or “tired” fuel pump.

Could the return of this long cold cranking and the relationship between the time starter motor spins the engine before it fires and the amount of fuel in the tank be the sign that one of the pumps is on its way out?

Can I switch the pump that runs all the time with the one that is energized only above 2800 rpm, provided they are the same? By switch I mean just swapping the connectors external to the reservoir (I don’t want to deal with the two submerged pumps unless there is a solid evidence that either pump is not doing its job)

Best regards,
Steve

PS The fuel pressure remains steady for at least an hour post shut-down, so I am reasonably sure the check valve is good.

33

Hi, new to the forum. I was just wondering if you ever found a solution to your intermittent stalling/no-run condition with FF77 code? I’m having similar trouble and searching for ideas.

34

Welcome to JL. As indicated in my earlier posts, the FF77 is gone and the long cranking upon start-up is sometimes happening, sometimes not. Not sure what it is/was. As you can see, everything was touched/replaced.
Probably I had a dirty/corroded connector somewhere.

The electronics of these cars are now 25 years old. Quirky and temperamental at times. I’ve learned that the car will never behave as new, even though everything ignition-related is new.

Best of luck,