'96 A4 1.8T sudden power loss under full load!

[Poikanen]

Hi, Only just joined so be gentle!!
I have recently test driven a 1996 A4 1.8T Sport. Its not a new car I know but I don't buy new cars & as its only 2 grand, it seems on the money!

A brief history is as follows. Bloke buys said car & 18 months ago cam belt snaps! Head rebuilt with new valves etc.

Late last year the car just stops!?

A mechanic friend removes the head & sees 3 pistons at the top which on a 4 potter is not good!
He struggles to find an engine & is quoted 1400ish quid for a rebuild with new crank, con rod, all bottom end shells & has bores honed & completely re-ringed. Owner says "OOps".
Turns out he still owes money to Mr Finance. The finance company recover their cash & offer my mate the car as payment for stripping the engine. He says Yes.

My mates boss pays for engine rebuild & I see it on the front for £2600. I ask him what he'd take & can have it for 2 grand.
I take it for a spin & am being gentle after the major internal surgery but when its warm I give it the gun just to see how they go & under hard acceleration, the turbo comes in & it violently cuts out as if I'd turned the key off during take off!

I don't have a lot of experience with turbo'd motors nor does my mates boss as it goes!
Everything seems to be piped up correctly & I've checked the boost control valve with the values given on autodata. It too seems fine.
I am drawn towards the wastegate actuator rod cos it looks like it has been repaired after being broken!
Does this rod need to be a certain length to control boost pressure?
I'm guessing it does & either the car is overboosting & shutting off or it thinks its overboosting & is doing the same.
Any ideas please without making this an expensive car & suffering main dealer labour rates??

Please help. Am i in the right area or should i walk away now??
Thanks for looking. Jonny.

 

[Poikanen]

Been on blower to Audi & am told if I take the car in to Doncaster dealer, a diagnostic is up to 100 quid. This is fine I say but can you tell me that it won't be more expensive & i will drive away knowing what the problem is?

"No" & "How long is a piece of string" is the reply. Could be a million things & cost nearly as much I'm guessing!
Thanks for nowt then!

I'm looking for a boost valve now so i can physically see what the boost is & if it is exceptionally high when it cuts out. Can a boost valve be inserted into the pipe from the wastegate with a t-piece? or does it have to go somewhere else. I'll cable tie it to the wipers for the sake of a quick road test. I've looked on Turbo Technics website & they tell you how to drive the car to check boost levels.

Does anyone know what boost 1.8T's run at & whats low or high please?

I've also emailed 4 rings spares as he isn't far away & thought a replacement wastegate & actuator removed from a car that doesn't appear to have been molested would be a good thing to try.

Please tell me if you think I'm wasting my time trying to suss this myself but i'm trying to think logically & save a few quid. I wiill give up though if enough people tell me! Honest!

Jonny.

 

[audi5e]

sounds like this car has a bit of a history. maybe it would be wise to stay away.

Not sure of turbo problems myself, so it could be a simple fix? but then again, like the audi guy said, it could also be friggin expensive?

others may have a different opinion.

 

[foolish3uk]

0.6 bar of boost is the spec, if it gets plugged in to vag com it should list a fault creating easy diagnosis,

 

[audi5e]

Audi has a technical support email address (can't remember off hand what it is) on their web site. You could try contacting them to get the length of the rod.

They have been reasonably helpful in the past. Also you are dealing with the manufacturer's tech guys direct instead of some dealer service adviser who is unlikely to have those kinds of specs.

 

[PaulJC84]

Check if the actuator moves. It may be stuck open.

And check the spark plugs.

Cheers.