fallenguitar

Hey, i recently bought a 5 speed audi 200 quattro 20v (1989) which did sit for a year. it has always had this minor lag during fast acceleration with boost, i thought it would be any easy fix, and will either hang up when i shift up a gear, lose torque, and either recover and SLOWLY accelerate, lurching while it does it, or i may have to down shift while going up a hill and will still slowly DECELERATE, this is at around 4000-5000rpms which doesn't fit.i don't normally do this either, just as a test, i baby this car. It has always been hard starting taking maybe 3-5s to finally start and sometimes stall out. it will also hang up during boost at around 4000rpm and won't budge, i can let off the gas and then accelerate again and it may happen again or work fine.

I have recently replaced: spark plugs, spark plug wires, distributor cap/rotor, fuel pump relay and module, air filter, fuel filter, hole in one of vacuum lines (which was replaced), and an 02 sensor. I have always ran 91 in it also.


I've been looking online and there are a wide variety of answers, the most common is that the fuel pump is shot(which it isn't, i did a fuel pressure test and the pressure was fine), a collapsing hose, mainly the breather hose and i have no way of testing if it is or not without having to replace it, and maybe a hole in a vacuum line except i don't know where to start/look. i did do a swift check with propane to see if there was any holes, but to no avail, what are the main hoses that start to deteriorate ? if there are any others solution that would be much appreciated!! this problem is killing me! (and my paycheck)

onfir3

1. An 89 200 is a 10v, MC2 (most likely, check if it has 1 or 2 knock sensors)
10v turbo engine
2. SJM is your friend.
http://www.sjmautotechnik.com/trouble_shooting/vac.html Intake vac leaks

http://www.sjmautotechnik.com/troubl...ing/ficis.html Fuel issue?

http://www.sjmautotechnik.com/troubl...ing/boost.html Boost issues

3. Do you have an actual boost gauge or the stock boost gauge? Either way, when you lay on it from about 1500-2000rpm, I mean Wide Open Throttle, Does the boost gauge read above 1.0Bar or 0 on an aftermarket gauge? It should creep up to at least 1.4bar. If not, boost leak/vac leak.

Common hoses to check are the "michelin man" hose, from the intake manifold to the intercooler. Carefully remove it and check for holes/cracks underneath. Sometimes it only leaks in boost because the pressure opens the holes up.
Next thing would be the "Igloo." or the hose over the fuel metering plate. had one of those spring a hole. Be careful when removing it. Check the inside for holes, easier to spot that way.
Then, Block breathers are on the drivers side of the engine, near the back, sort of below the dizzy cap. Should be able to see it.
Finally, for Vac leaks that I know/have seen, I would say fuel injector o-rings and shrouds. Their are o-rings around the injectors themselves, and 2 for the plastic and brass inserts. They are cheap, but you'll probably break the plastic insert trying to get those out. Common Vac leak here, and replace with green viton seals around the injectors.

Lastly, Slow cranking. Ok, this might be a few issues. Fuel injectors may be leaking. This is my guess. I would make it so the car can't start, by taking the plug wires out or etc (be careful for open spark, working with fuel here.) and then you need to pop out the injectors. Put them in glass jars. crank the car over and check the spray pattern. Should be a nice cone. if not, they are dirty. Then, you need to let the car sit for a while and see if the injectors leak down. Perhaps empty the jars and let it sit for an hour or three. What happens is there is pressure between the fuel block and the injectors, and the injectors let the fuel slip by over time, causing slow/long cranking after sitting. First remedy may be soaking in seafoam and running 1/2 can through the fuel tank. Crapshot. After that, need new injectors.


Long winded, hope it helps, good luck.

fallenguitar

ok, well i have stock boost gauge and it will read up to 1.4 bar when floored at 1500-2000rpms, the turbo was replaced around 3 years ago but i dont know if it is bigger or not because the paper work just says "replaced turbocharger". i think its the same, if not close too because the mechanic that worked on it is familiar with these imports. im going to swing by their shop soon and ask them a couple questions about that.

ill check out those hoses asap and get those fuel injectors cleaned. i did use some fuel injector cleaner a while ago, but soaking them may lead to more/better results, hopefully i dont need to replace those!

Thanks for the help! ill let you know the results, school and work have been tying me down so it may take a while..

billy34

but after I push it hard, in particular up a hill, it stalls completely
when coming to a stop. Often it won't start again at all until it sits.
At first I thought it was heat related (temp sensors: had that issue years ago), but it happened yesterday only half warmed up after pushing it on a steep hill.

Ideas? Seems like it's getting flooded?

fallenguitar

I actually had that problem too, it was a vacuum leak in one of the turbo lines, it would always stall out when i was doing corners and take a good 5 minutes of patiently waiting to be able to successfully start.

Hope this helps!

billy34

Thank you!

briangates

Did you ever solve this issue? i know this threads nine years old but im having similar issues with my 87 5000CSTQ MC1, loses power going up hill and above 3000RPM my CEL will pop on till i let of the gas. Flashing codes gives me 2141, i run nothing but 93 Fuel and its really starting to confuse me.