If you have a vacuum leak it can be more prominent at idle as there is a greater dilution of air.
If you have cleaned the oil out of your plug bores i would move on to your smoke test.
If it is always the same cylinders you could swap coil pack with two known good cylinders to rule that out.
My cats are bad and you can tell by testing in going and outgoing temps but if i give it a goof thrashing it sorts itself.

Check for vacuum leak first as you have mentioned that clip on pipe before but can be around the throttle body seal or many other places.

The fuel trim indicates air again i would say, so you are looking at MAF and O2 sensors but again check for air leaks first
 
Spraying brake/carb cleaner or (carefully) easistart around the manifold, throttle body, intake ducting and PCV valve can also give similar results - if the rev note changes when applied, there could be a leak!
 
Hi all - not had a chance to do the smoke test yet booked for next week however it’s stalling now and progressively getting worse, it doesn’t alway out a code in the only code I’ve had this week is multiple fuel trim 2 limit reached, however it is stalling more and more often, usually on riding up to a junction or letting off the accelerator to go around a corner, it did it 3 times in 30mins today. I disconnected the maf if anything it got a little worse... any ideas?
 
Hmmm....yep....

Does it stall like just die....or is it as similar to being in a manual car and you forget to press the clutch and it kind struggles, stutters, judders and dies!?
 
danwilderspin said:
Urm I didn’t pay that much attention I will next time are there different answers for both?
Click to expand...
Yep....one is fuel, spark and air....and the other is the gearbox Torque Converter Lock Up Clutch not letting go and stallign the car.
 
Ok saint unless it very unlucky and it’s both it definitely just dies, I started it from warm and it stalled wotought going into gear did it three times until I feathered the throttle and out in reverse, it was very lumpy reversing until I got going. I have maf disconnected and it seems to be doing similar so maybe time to rule that out. From cold it never stalls which is normally how we drive her, morning and evening i imagine the emission controls with the high idle is the reason for that now
 
Ok - more drama this morning seems to be getting worse - maf still disconnected -

Started it from cold stalled straight away.
Started again kept revs on and out into drive with foot down and the revs would not climb?? Then tried reverse and it crawled back ok then out into drive and it slowly sprung into life, all the while shaking like it had dropped a bank! No eml though! Any ideas? What the chance of a bank 1 cam sensor or a crank sensor?
 
Hmmmmm.....are you getting any error codes akin to ..... Bank 'X' Cam 'Y' timing to retarded.....?
 
Nope no timing faults whatsoever.

This evening I am going to reroute the right air cable that comes off the maf elbow as I think it’s wrong hence why it’s right.

Also going to plug maf back in, clean the icv and do an oil/filter change as I dumped some oil treatment in about 4K a go for treating noisy lifters which wasn’t the problem in the end.

Don’t know if it will all help or not.

It’s booked in next Tuesday for a smoke test then I can rule in or out air leaks
 
Right this got real bad now... driving back home started her up died about 4 times until I held throttle. It then started backfiring massively from somewhere under the car so loud everyone was looking at me. Turned it off and filmed this video backfire is quite quiet on the video. Faults are now not mixture related but maybe as maf was disconnected, I have cylinder 1/2 misfire and severel cylinder misfire codes.



Argh..

Again once you get going and it sorts itself out it’s fine?
 
Final point for now - managed to re route the hose going from back of engine to the intake elbow as it was very tight maybe leaking, also swapped cyl 1 and 3 cool to see if the misfire follows if it comes back, but since connected the maf back its ran fine, no eml stalling etc , however the original two codes were back - additive fuel trim 1 and 2 limit reached.

Also squirted contact cleaner around the whole intake boot, no leak there. I guess I will have to wait for the smoke test Tuesday if it doesnt throw anything up I’m tempted with a new maf and I will take it back if it doesn’t fix and move on from there...
 
Have a read up on testing your cats using a laser thermometer but I still think it’s air related
You could do with running live data on it
 
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