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hi can any one help. iv got a 1999 s4 and went petrol station yesterday and on way home car just felt slow and sounded different.also started drinking fuel.its had new maf last year.new audi tt diverter valves.and a custom mrc remap.was thinking boost leak but not sure.thanxs

Could be an egt, when they fail the car overfuels to protect the engine.

You need to get someone with VagCom to scan it.

s4bainsy wrote:hi can any one help. iv got a 1999 s4 and went petrol station yesterday and on way home car just felt slow and sounded different.also started drinking fuel.its had new maf last year.new audi tt diverter valves.and a custom mrc remap.was thinking boost leak but not sure.thanxs

Has it gone into limp mode? Do you have a boost guage? Do you have VAG COM?

Where are you in the UK?

just booked her in at unit 20 on monday.dont think car is making any boost.there going to give it a boost leak test and vag com.thanxs

Similar problem.

yorkie wrote:Could be an egt, when they fail the car overfuels to protect the engine.

You need to get someone with VagCom to scan it.

Whats an egt?
Vagcom showed overfuelling, boost fluxuations/negative deviations cant remember what else. While mech had it it also ran up to 4k rpm and boost was fluttering, as if hitting limiter.
I had a emergency checkin and had to run up to aberdeen in it.
Engine management light came on and dropped into limp, pulled in and shut down. Cooled for a couple of mins but had to keep going to make checkin.
Started up and ran as before but not in limp. had to repeat this several times.
Left the car for 4/5 days while offshore and the run down was perfect (except the power loss)
Boost leak testing tomorrow (if its dry) and servicing asap.
Anything else that you lot can think of?

egt sensor, lives in the turbo, measures ex temp, had 1 go on mine , same probs, get vag com on it. usually caused by a bad maf thats not reading correct air flow so car runs lean, burns out egt and lambda sensors.

Cheers for that, will have to see how it performs tomorrow.
I did a full service on it today, oil/filter, air fliter, fuel filter, pollen filter, plugs etc.
Went to do the afterrun mod and failed miserably at pulling the old switch out (scared i mangle it and cant get it out)
Audi gave me the wrong brake fluid reservoir (mines cracked) so taking that in tomorrow morning, picking up new one and TBB.
While servicing i had a wee feel about the hoses. Stuck my hand up underneath the TBB and its split underneath at just before the big jubilee, probably the full underside.

MilkybarKid wrote:Stuck my hand up underneath the TBB and its split underneath at just before the big jubilee, probably the full underside.

There's your boost leak(or at least, there's one boost leak)! Unplug the N75 (brown connector just to the left of the back of the Y-pipe) before you drive it, otherwise you risk overspinning and killing the turbos.

Did that by chance when i was checking all the sensors/connections before i sparked up, cheers bud could have been costly, and as you say "or at least, there's one boost leak"
I found another while changing it this morning, the small barb connection on ns dump valve has a small hole in it (possibly from when i took off the TBB) so need to check that out properly in the morning.
Took it a run up to loch lomond today and difference is night and day. leak test tomrrow and ill see if ive sprung any more.

BTW totally off topic this (and sorry for the thread hijack) but supercharged 1.8 and v6 engines should never be allowed in jet skis!!! jet skis by name....

Turbo failure after around 1000+miles.
Down to the pod for vw action, ran beautifully, took it easy down, 70 all the way (truthfully).
Regd to race on sunday, started raining, waited an hour and still nothing happening, packed up and left.
Got to the junction outside the grounds, checked who was whistling behind me, thought it was the corrado vr6 behind me, sounded like it was SCd.
Pulled away from the junction and "wooooooooooooooooooo" "<beep>."
Now locked up in my garage, had to be replaced by the gto til i get it sorted