P38A I may have a reprieve......

......in typical Ebay fashion, the P38 was sold, then the buyer has been a little lacklustre in replies.

After chatting with the other half, and as it isn't costing us any money currently - not taxed, MOT'd or insured at the moment - and I have so far managed to keep the head of site at bay regards removing from the site - and my own frustrations that I haven't yet been able to get to the bottom of the problem, she said we may as well keep it at the moment. Man, I love that woman!

Any how - here's the current skinny......

MAF unplugged:

• Will rev unloaded up to 5k and then begin to pop and fart, backfire through the intake etc
• Loads of white smoke of unburnt fuel from exhaust, on the over run after a revving session, will pop thriugh exhaust
• Not keen on heavy acceleration, but with light throttle control will get up to 50

MAF plugged in:

• Will not rev unloaded past 3k, with banging and popping, won't hold a steady high rpm without faltering revs dropping and popping and backfiring
• Doesn't like to drive unless you very very lightly use the throttle
• Not so much white smoke and nowhere near as much of unburnt fuel in the exhaust

I have tried a new (aftermarket) MAF, and it ran worse.....

Unplug the MAF while running and she'll stall....

Will not start with MAF unplugged UNLESS you keep the revs above 500rpm for the first few seconds and then she'll idle.....

So I whilst I was initially thinking Cam wear, the fact that unplugging the MAF has a dramatic effect on the running then it is most likely not a mechanical issue causing the huge majority of the running problems but either a MAF issue, an O2 sensor issue or a combination of both.....

Thoughts? (before she changes her mind and insists we sell it again!)

If you sell it M8 you'll regret it, i guarantee it, i also said that in your other thread!

fate wah! she doesn't want to leave ya!


It doesn't seem to be mechanical as your video showing the cam, showed it was in good condition..

And mucking about with the MAF wouldn't affect the running.

Could be a combination of O2 and MAF and various other sensors..

Have you had the injectors checked?

Ignition system in ok order?

Could also be a crank sensor sħitting itself.

Ant I have some where knocking about a brand new genuine o2 sensor your welcome to try it I will have a dig around the garage tomorrow mate

Happy for you.
And if you still have then you can figure out what the trouble is .
If sold you would spend a long time thinking of "what ifs"

Congrats!
Its going to be something of an "Aha!" moment when you resolve it, I bet.

Keep going.... we all want a positive result for you.

+1 on the injectors.
If you can get a multi trace scope on them you could check the pulse widths are all the same and that would suggest that the ecu is OK.
Could it not just be an injector leaking fuel all the time? That would manifest on gas as well.
That said, popping and farting normally is more to do with timing (of fuel or spark or cam) allowing the explosions to escape into the inlet or exhaust but excess fuel can cause it too.

I think he's already had noid lights on the injectors.

New MAF makes no difference but have we checked the cables and connectors are sound?