Boost issues.

[alg]

Is it sorted ??

[mcandmar]

I doubt its your issue but check the ignition switch at the key. I had one go faulty and would cut the engine if the key was wiggled around, hitting large pot holes or speed ramps too quick would also do it with the weight of the key ring hanging from it. Would explain the random cuts, and difficulty starting.

[alg]

My wire to the WGFV broke in the plug. This gave 0.4 boost & intermittent full boost & clicked when tested initially. Then Mihnea played with it enough to make it fail & Doug soldered it. Any help ?

Or you could come & look at my lovely RS2 & make an offer !!


Oh & no codes on vagcom.

I am going to miss all this

[Error404]

Hopefully you went direct to Bosch for the knock sensors Jase as per the OEM parts thread? - 1/3 the price of the stealer

I've no experience of motronic faults but had a knock sensor go bad a while ago on the CQ without any fault codes or owt, started with a bit of chugging occasionally, and then developed into the whole rev range becoming a flat spot

Hope the knock sensors sort it, and at least you'll have loads more good spares once its sorted

[Paulgo]

Hope you get it sorted matey - and these sort of problems do get ya down when you just cant get to the root of the it! Got to be one of the things you've got left to try and sure you'll have her back to best by the weekend

[Rusty]

Sounds like wiring as you've replaced all the sensors. I had a plug go funny and had na intermittent starting issue, it was the crank position sensor. Might be worth wiggling a few of the connectors at teh back of the bay and seeing what happens, otherwise take each plug apart, check it and re-assemble, might cure the problem like I did...

[s2_bo]

Just another thought, could it be that the WGFV even though new is not working?
I recently bought on from audi and it turned out to be dead. Had it replaced and now its fine..

I doubt its that but maybe worth a try.

[S2central.net]

I doubt its an FPR issue - if it was low pressure and therefore running lean enough to cause excessive knock at high boost (which in turn results in active boost shutdown) - it should also be throwing up mixture adaptation faults on the ECU. You do have to hate these cars sometimes... But then if they were as easy to work on as a Ford Fiesta then everyone would want one

[macspring]

Jas11n,

Not worth anything I know, but I feel your annoyance with it.

Wishing you and it a speedy recovery.

It will be interesting for all to note what it turns out to be, when you nail it.

Good luck.

[A80Avant]

if you want to try out an FPR i have a new one 4bar

[Jas11n]

Thanks for suggestion all. At this stage I'm not ruling anything out.
I'd not be in the least bit surprised if it turned out to be a blown sidelight bulb

is it worth having a look at the cats? i know you replaced them recently but wonderd if they might have broken down?

Hmm, good thought. I'll take both off and have a look.

Absolutely sure its air tight including PCV system ?

Yup, as tight as me.

Jase,

Is it possible that the cutting out was due to an immobiliser fault in your original ECU or key reader and that once you changed to your non immobiliser ECU you lost the cutting out fault but gained the boost limit issue due to some wiring incompatability/country code sort of issue from fitting a non immobiliser ECU into an immobiliser loomed car.

Sorry if it's a rubbish suggestion...............

John

I still haven't ruled out an ECU problem Johne. It keeps on rearing it's head when I'm pouring over the possibilities. I'm going to try my bro's immo ECU at the weekend. I'll need to match it to mine, but that's easy enough in vag-com.

Fuel pressure reg?

Would low fuel pressure limit boost constantly to 0.4bar?

[A90TURBO]

Fuel pressure reg?

[johne]

Jase,

Is it possible that the cutting out was due to an immobiliser fault in your original ECU or key reader and that once you changed to your non immobiliser ECU you lost the cutting out fault but gained the boost limit issue due to some wiring incompatability/country code sort of issue from fitting a non immobiliser ECU into an immobiliser loomed car.

Sorry if it's a rubbish suggestion...............

John

[S2central.net]

Thanks for the feedback guys.
Fitted the new MFTS today and as suspected..........no change.
Waiting on the new knock sensors arriving and I'll test the wastegate diaphram tomorrow with a vacuum pump down at my local specialists (just incase the caps full of hydrochloric acid or something, knowing my luck at the minute )

Mmmmmm - this is a funny one... Was gonna suggest when I saw MFTS missing from your initial list.

Could well be knock sensors - they only give fault codes if they go open or short circuit - if they provide rubbish info the ECU doesn't complain...

Absolutely sure its air tight including PCV system ?

[gavs20v]

is it worth having a look at the cats? i know you replaced them recently but wonderd if they might have broken down?