Scooby has developed a fault over the last two weeks.
Details: MY95 UK 56Kmiles
de cat downpipe
BOV
ITG panel filter
scoobyECU
@ 75mph cruise speed it will hesitate/ stutter once after a short period at this speed then ok for a short distance then stutter again.
Also the idle is dipping down to almost 0 when coming to a halt, then after one dip settles at 800/900 rpm. This appears to be more apparent when stopping from 70mph than 30mph
Nothing showing on knocklink but appear to be getting more "popping" lately
Can anyone shed any light please ?
Cheers

 

Low reading lambda causing ECU to heavily over fuel in closed loop mode?

Richard

 

...excessively rich AFR due to VTA dump valve?
...or knackered MAF due to ITG panel filter?

 

Is there any way to check which of these it may be without buying lots of new bits ?

 

Personally, my money's on the MAF. If you've got torx bits, you could remove it. Be gentle though, as it's fragile. Check if the element is covered in gunk. You could try cleaning it, however, you may be better off getting a replacement...

 

or try a mate's MAF for 10 mins to see if it clears the problem.
IIRC on the pre 99 MAF's you have to buy the whole housing - which ain't cheap.
Ask the dealer if you can try b4 you buy.

Chris

 

Yep, I think this is the first step but I may need it for a day or 2, rather than 10 mins as its not happening that often yet!!!

 

I thought the older MAF's didn't fail as regularly as my99/00? Is it happening only at low loads, or also on boost? If on boost, it could be lots of other things too - are you sure your knocklink is working.... ?

Richard
PS: since when did ITG panels start knackering MAF's?

 

That was sarcasm, wasn't it...?!

 

be4 yu do anything connect yur diagnostic connectors under the steering column and above the pedals .2 are green and 2 are black.the black ones are yur diagnostic mode if yu like.once connected drive the car for a minute park up and count the CELs.(check enginge light flashes) long flashes indicate 10s and quick flashes indicate 1s .if it flashes quickly constantly then yu have no error codes .if it does produce a code yu can find which sensor it is either by searching or give the code here and i can tell yu what it is.better than guessing m8

 

Had the car on the select monitor yesterday - No error codes.
Idle was being caused by BOV not closing fully. -still have hesitation though
I have dissasembled & cleaned the MAF, It looks fine - not too dirty.
It appears to be happening @ 3100prm in 5th,
I have "borrowed" a coil pack to see if any of them are cracked/shorting out.
Knocklink flashes when sensor tapped in engine bay so I wouls say this is working Ok?