Engine sat for 2 month, now 2 issues

My high compression 4.2 was running very nicely before it sat for 2 months while I replaced the water pump and swapped over to the T5.

1 - The first issue is when I hit the starter. I used to hit the starter and crack the throttle, and it would start right up. I never use the AED.

Now, to get it to start I have to turn the starter with throttle closed, and every time it backfires out of the AED. I can see the puff of gas / smoke blast straight up from between the carbs (hood open). Once it does that it usually starts. After a minute or two giving it some revs it’ll idle nicely. The pump stops clicking and the floats dont over flow, and the mixture is good (I have O2 sensors). Is my AED flooding or is something stuck?

2 - My PCV hose is connected to my intake forward of the carbs. Before, it might have a teeny bit of oil in there but nothing remarkable. I never noticed much coming out of that hose, tho honestly I never investigated it much. I’ve now noticed that with the hose disconnected there’s visible puffing. Not a huge amount but consistent puffs coming out of the hose, and noticeable oil / fuel on the fitting. What possible could cause such a change in blowby from just sitting for 2 months? I turned the engine periodically too, it wasn’t completely still. Could something else be causing this, or did I lose some compression? Or is a bit of puffing from the hose normal?


Probably sulking from not being used for so long, have you taken it out to its favourite piece of road and given it a bit of a run.
Try showing it a bit of love and see if she responds, you know how ladies can sulk sometimes.

Mine’s a bloke. Name’s Wilson. Comes good if we drive to the pub with the cricket on the radio.

Tweety was a “he;” just could never see a car as brutish as it could be, be a she.


OK folks. I’ve now taken the car for 2 one hour plus rips around town, and an hour on the highway. Same issues. What to check on the AED? It spits gas at startup and is hard to start. Smells like fuel. Then once the engine runs for a minute it clears out. Float issue? Is there some way to take the unit apart and see what’s going on in there? I’ve never used it and never bothered to touch it…

I presume you are talking about a HS8 equipped 4.2 with AED, not older ASC.

If so, there is a kit that converts the AED itself to manual choke operation
some on here have fitted that

Mine has the AED entirely removed, and replaced by a manual choke parts that lowers jets.

It gives precision & fully variable control over engine richness during warm up, which is very desirable imo

It’s dual HD8’s with an AED. I have it unplugged. I’m going to look at the manual and see if in the meantime I can lean it out as much as possible to try to stop it from filling with fuel. The floats stop the pump, so the bowls aren’t overfull, just seems like something isn’t quite right with the AED.

I’ve been doing some reading about converting away from the AED, I believe my carbs do have the movable jets but they are set to be static. Perhaps that’s a good option.

I have and AED on my Series 1 XJ6, some time ago I got the below off eBay. I have yet to fit it up on my original/spare AED. It sits on the top and use cams to work the mixture and air volume.


That’s what was on my S11, threw it away a few months ago and just rigged the choke cable to lower the rear carb jet, luckily we only have mild winter temps in Auckland so just a little cranking to get her to start.
When I have the XJR back on the road I might think about getting the set up to operate both jets.
Replacement diff for the XJR arrives on Monday.

Our temps are mild also in Sydney. In winter my AED runs too long. I will set this up as I have all I need to do it. Good luck against the Poms on Sunday.

I live in Socal and have never used the AED, I just crank a few times till the engine starts, hold the revs at about 1000 for 30 seconds, and then it idles fine and warms up. I never used the AED. I took it apart, cleaned everything, and made sure everything was ‘closed’. On startup, same thing, big puff of fuel from the needle and air holes. Then started up and ran fine… Now I’m thinking it’s not the carbs but something going on with the engine that is building up pressure and releasing before the motor starts?

OK, any thoughts would be appreciated, not sure what else to check. I’ve driven the car every weekend for 2+ months, including hard runs on the highway. It runs beautifully once it starts, but EVERY time I cold start it it does this. Turns over and starts to fire, when I let off the button it coughs and POP blasted a cloud of air/fuel back through the carbs. It seems to puff out from the AED. I let it dissipate for a few seconds, hit the starter again, and usually it starts and runs. Sometimes it’ll puff a second time, then start. Everything is tight, doesn’t seem to be an air leak or any loose wires or any other issues. Once the car fires it runs smoothly and evenly. Thoughts?

Slightly lean on cold start? I used to run an engine in SoCal with the AED off. Had spitback at cold start, so increased fuel richness. Ran for quite a while just fine that way. Then got interested in how rich it was at warm idle and found the warm idle was too rich. Added AED and leaned out to correct fuel A/F at warm idle, no more spitback now either. I added the AED but wired with manual control under the dash.

That’s what I’m guessing but strangely enough once it catches it runs / idles around 12.5 A/F until it gets a bit warmer, which is right on. I’ve tried with the AED on and same issue. I just popped off my air box and suspect an air leak on the rear carb is making it too lean at crank but once it fires the carb balances out the mix? I’m going to fix my air box and try that.