chuckles4kq

My early 89 200t (mc single knock 10v) engine is really crapping out at 4000 rpm. ALSO, when I floor it, it will just stutter & choke. But that only happens under load when driving (uphill is worse). IF I keep a light foot on the accelerator, i can drive the car. But it's annoying me because there's so much power (and enjoyment) that's missing out. The computer blinks out a 4-4-4-4 every time I check it. Residual fuel pressure is being held overnight, and I even went as far as to punch a hole through the fuel filter since I thoguht it might have gotten 'wet' with water. I haven't checked the fuel pressure. But it just doesn't seem like a fuel problem. There are no detectable vacuum leaks either.

What else to check?

cuatrokoop

waste gate hoses...or the WG itself. the '88 5kt we were looking at would get to 3800rpm or so and just not work. light pressure on the gas and it'd go...haevy foot, full boost, no go. check those things out.

force5auto has used WG's for $50 plus shipping btw...

chuckles4kq

is there any way to test if this is the problem before I go tearing though it? (check spring pressure, someting?!?)

thanks!

Aldo

Commonly known as the Michelin man hose. Is this original? Have you taken it off and checked it thoroughly for leaks? All of your turbo hoses down below this? Just a thing to definitely check! Sure sounds like a big leak under boost problem. Is the throttle switch original?

www.sjmautotechnik.com

chuckles4kq

most of these hoses appear to be relatively recent. As for the throttle switch, I can only guess on that.

Are there any other opinions regarding the wastegate theory?

SteveAngry

remove the Michelen man hose and inspect it? It's almost impossible to see any of the cracks in it with it still in the car...

Also, check the hoses coming off the WG. If I remember right, the cloth hose back there likes to rot out...

Steve
Michigan

cuatrokoop

i would imagine if that cloth braided hose didn't rot, then possibly the diaphragm in the WG went bad...both have finite life spans.

also, any michelin man hose on an audi i have come across had cracks in it, or was prone to cracking. i had to replace the CQ's twice, and its not even a turbo. headers = hot, DOHC engine = hot. the 5kq hose should be replaced, as its looking pretty dried out.

srigs

I had a simular problem with my 86 5000 CS Turbo and my 89 200 CS Turbo.

The Michelin man hose brakes at the bottom of one of the folds. Take off and check it. It happened to both cars. Get rid of Bosh Platnum spark plugs with NKGs and what a difference. Our 10 valve turbos don't like'um. (Check out www.intendedacceleration.com for this tip) My older 86 5000 CS Turbo had injector clogging problems. Short term do some Techron fuel additive.

Hope this helps.