I’ve owned this car since 1999, had it serviced regularly, and usually drive 15 miles twice a month at least, each time. When I bought the car in 1999, engine was rebuilt and I’d say it’s the smoothest running series 3 Xj6 I’ve ever driven.
So, yesterday, Friday, I set out on a 15 mile drive to visit with some friends. I hadn’t driven the car for nearly three weeks. So, when I started it up, the engine had a rough idle which I attributed to the necessity of tightening up the crimp connectors coming from the ‘pigtail’ section of the CTS connected to the wires leading to the ECU in the boot. I’ve had to do this every few years. After the engine began to warm up after two minutes of idling, smooth operation returned so I decided to tighten the connectors later after returning home and the engine had cooled down. Today I decided to take a drive to confirm if the problem had been rectified. I started up the car and pulled out of my garage and was pleased to find the engine behaving as it should. However, after two minutes of driving, the engine lost power and stalled. I pulled over wondering what could be wrong. I remembered that 9 years ago I encountered a similar problem on my 1986 car. At that time, I called auto club to give me a tow home. The driver at that time said the problem might be the fuel pump. He took out a wrench and used it to softly tap on the fuel pump for several minutes, after which he instructed me to start up the engine. It sprang to life. He told me to continue my drive home, park the car in my garage, and not take it out again until I’d replaced the fuel pump and fuel filter, which I did. That car has been running well ever since. Today, I foolishly drove the '87 car five miles more since after tapping on the fuel pump and switching fuel tanks, the car was running smooth as could be, and I decided it would be a good idea to top up both tanks with fresh fuel. I parked in a shopping center for about an hour, and then began to drive home. After a minute of driving, the hesitation and stalling began once more. I didn’t want to call the auto club just yet, so I got out of the car, went in to the boot, and tapped the fuel pump repeatedly with a wrench. Each time I did this I was able to get the car started and drive a mile or two before it would stall again. I did make it home eventually, but before I contact one of the ‘usual suspects’ to purchase a new fuel pump and fuel filter, does the filter which was last replaced back in 2014 ( I found the receipts), sound like it would be the culprit here,since the car has been driven close to 50,000 miles since then? Advice would be most welcome. Thanks
Mel,
1st up i needed a coffee & a lay down - exhausting reading all that, any upgrades with fuel mainly fuel pump it’s best to replace fuel filter to bolster you warranty on a fuel pump, you certainly have a vital mechanics tool in your kit & that’s something to hit things with…normally called a “bommie knocker”…is the fuel pump a serviceable type?
If I’ll be replacing the fuel pump I’d definitely replace the filter as well. Before I order parts, I’d just like to hear encouragement and/ or validation the pump and/ or filter are the culprits here, rather than the possibility of the culprit being the fuel pressure regulator, which I’m hoping is not a problem since when the engine runs smoothly after giving the fuel pump a good whacking, the fuel pump and filter would seem to be the defective components. I don’t know if the fuel pump is in fact ‘serviceable’, I’d just as soon be inclined to purchase a new one since this one has been in the car for almost ten years. Thank you for your patience.
Easy first step, Mel; select ‘D’ and turn key to ‘crank’ - the engine won’t crank but you should hear the pump running. If it does; select ‘P’ and crank - if the engine starts, so be it. Repeat whenever problem occurs - it sounds like an intermittent fault…
When the pump fails to run; banging on it adds insult to injury - check if the pump has power. If ‘yes’, replace the pump - it has failed. Maybe clogged by debris from the tank - which in itself may cause intermittent faults…
The main point is to sort out whether you have a pump problem, electric or mechanical - or if there is a problem with fuel supply to the pump. The latter would almost certainly relate to ‘dirty’ fuel - tank debris intermittently clogging pump or changeover valve. The solution then is the drain taps, clearing debris - but nominally selecting the other tank ‘should’ result in instant engine recovery…
The main filter would not cause such intermittent faults, but assembled dirt in it would not be helpful…
And of course; do not neglect other sources of such intermittent engine problems…
I just revisited my file of receipts and found to my amazement, the fuel pump and fuel filter were not replaced in 2014 but rather in 2004 which would be 40000 miles and close to 20 years ago. The pump is getting power, and I did make it home eventually albeit with several unscheduled stops on the way. So With these new details which have come to light,would you agree the purchase of a new pump and filter would be advisable with a reasonable chance of success? Thanks
Mel R
the submersible pumps you can just replace the motor into the old housing, age gets to everything including us,the good thing is you can replace the parts on a car…our bodies??? well that’s a different story
Did it actually run when tested, Mel - and the engine started…?
The pump has served you well for a long time and can be retired with honour - the filter is scheduled maintenance replacement. Little is lost by replacing them…
However, success depends on the parts being the cause. ‘Obviously’ the engine is starved of fuel, which may be a clogged changeover valve etc - a fuel pressure test may reveal a faulty pump - but not conclusively eliminate other factors…
The easy way is simply to change the pump and see what happens - with a ‘reasonable’ chance of success…
I will order pump & filter and report back when installation has been done. Thank you, Frank.
Mel R.
Frank_Andersen
July 9
MRCHB:
…The pump is getting power,
Did it actually run when tested, Mel - and the engine started…?
would you agree the purchase of a new pump and filter would be advisable with a reasonable chance of success?
The pump has served you well for a long time and can be retired with honour - the filter is scheduled maintenance replacement. Little is lost by replacing them…
However, success depends on the parts being the cause. ‘Obviously’ the engine is starved of fuel, which may be a clogged changeover valve etc - a fuel pressure test may reveal a faulty pump - but not conclusively eliminate other factors…
The easy way is simply to change the pump and see what happens - with a ‘reasonable’ chance of success…
Pumps do fail. On most of us, they fail due to leaking fuel, not because of pumping issues, though.
So, I’d be inclined to check the state of fuel supplied to the pump. If it is dirty, the problem might be upstream and a new pump might quickly be shot again.
Not wanting to discourage you, but it might be helpful to identify the problem (right or left tank), then running one tank empty and peeking in with a USB endoscope.
Thank you Aristedes. I think Bosch 69536 will be the way to go, it’s offered on Rock Auto.com at a reasonable price. I contacted one of the ‘usual suppliers’ I’ve worked with for years, and for reasons I cannot comprehend they claimed my car uses a ‘submersible’ type pump which is absolutely wrong, so I think I’ll have to purchase a Bosch 69536 from a different vendor. Thanks for the note.
Mel R
I’m still waiting for the new fuel pump and filter to arrive. Meanwhile, for curiosity I started up the car today. It ran perfectly and I let it run for 10 minutes waiting for it to reach operating temperature. I even turned the air conditioner on and it still ran well, I then even switched fuel tanks and it continued to run flawlessly I wasn’t about to risk taking it for a drive after the difficulty I encountered several days ago but at least I’m convinced my fuel tanks and switches are not compromised and I’m guessing the old fuel pump and maybe filter are on their last legs, and I’m hopeful the new pump and filter will solve the problem. Thanks
Mel, old fuel is poison for your car, at least drain tanks and purge all fuel lines. Make damn sure tanks are clean and replace all filters. Add two in the trunk from each tank if you don’t already have them.
Your fuel pump is in the same state of failure as a dodgy starter motor. It could push fuel for another 100 miles, or another 100 inches before finally and decidely stopping forever. In the automotive diagnostic world one of the most satisfying scenarios is a fuel delivery problem that is ‘fixed’ by tapping on the pump. The car is parked, and a new pump is ordered.
I’m inclined to agree with you Paetersen. I’m actually feeling ‘lucky.’ as I did indeed experience the ‘most satisfying scenario’ having made it home to my garage. New pump and filter should arrive in a few days, at which time I plan on installing them. Though I appreciate Slofut’s admonition regarding the fuel tanks and fuel lines, I believe the old fuel pump and or the fuel filter are the culprits here. This car is driven several times a month, always filled at the same reputable petrol station regularly along with my other cars, and I don’t think ‘old fuel’ is an issue here. I’ll post an update once the new parts have arrived and been installed. Thanks to all for your advice & encouragement.
Busch new fuel pump and new fuel filter arrived yesterday, installed both of them, went for a scenic drive today, no problem encountered, all is good. Thanks for your recommendations.
Cheers
Mel R
