Stalling, idling problem on 90 TSi

[nube90]

Hey guys I just looked at my first TSi im going to buy its a 1990 with 130k but it dosent idle correctly and when your driving and take it out of gear it dies but the motor is strong and the boost comes in quick around 3k and holds at 12psi. Any ideas of what might be causing this I have to drive home tommorow and I dont want it stalling on the way home.

 

[Rex2342]

It could be any number of things. Bad IAC, bad ECU, fouled plugs, bad coil pack, bad battery, clogged fuel filter...... the list could go on and on. If you have to just get it on a flatbed to bring it home and work with it from there.

 

[nube90]

Well its not throwing any lights except the coolant light and it runs good except when idling.

 

[Rex2342]

It could also be a vacuum/boost leak. It's best to just get it home and then diagnose the problem from there. If it were me and the car started everytime it stalls and runs good enough to get you home I would just drive it. If there is anything other than the stalling issues like nasty noises and sputtering/hesitating I would get a flatbed.

 

[ROOKIE1]

Mod list on car ? Check the Biss . On top of throttle body ( base idle set screw ) .

 

[nube90]

The car does not sputter or hesitate power is delivered smooth. The car is bone stock, thats what I was thinking the idle screw or a vacum leak. When your driving and take it out of gear it stalls almost immediatley.
I think it would be safe to drive home as long as I kept it in gear.

 

[Rex2342]

The car does not sputter or hesitate power is delivered smooth. The car is bone stock, thats what I was thinking the idle screw or a vacum leak. When your driving and take it out of gear it stalls almost immediatley.
I think it would be safe to drive home as long as I kept it in gear.

That decision is up to you. If you feel the car will make it I say go for it. Just don't put yourself in a situation that could get you hurt or ruin your new toy!

 

[nube90]

Yep I was just wandering if I could fix it before I drove it home. Im getting a good deal on it only 800 bucks.

 

[ROOKIE1]

How many miles ? Dirty throttle body ? Maf not hooked up ? Ecu caps ?

 

[nube90]

It has 130k um by throttle body when mean the plate right? Maf is hooked up, what are Ecu caps? Im new to Turbo.

 

[ROOKIE1]

The plate , correct . Caps are capicitors in the ecu ( under stereo ) that in the 1 g models are known to start leaking . Can cause erratic operation when they start leaking onto the board . Check vfaq.com on that .

 

[ROOKIE1]

http://www.tmo.com/howto/ecu1g/caps.htm

 

[nube90]

Well there is no chattering or bad smell. Maybe this will help the car will idle but acts like its going to die when idling but dosent.

 

[ROOKIE1]

I already replace my ecu . It did not chatter or smell , but caps were leaking . My car would start most of the time . Hard to start when cold , bad idle . Other times no problem at all . With the year of vehicle it is worth taking it out and checking . May see signs of early leakage that can be fixed before it destroys the board . Or you could wait and spend a few hundred on an ecu later .

 

[nube90]

Can you tell me where the BISS screw is located.

 

[ROOKIE1]

Here you go . Courtesy of vfaq.com .

 

[nube90]

Thanks, I was listening to the motor while its idling and it kind of sounds like its missing but could that be because its only idling at about 450-500. Once I give it gas its fine.

 

[ROOKIE1]

Have you replaced plugs and wires yet ? You should also check the connection on your injectors . Alot of times they get dried out from the excess heat of our engines . They tend to crack and not seat properly , so you get irregular pulses of fuel . If anyone has ever messed with those , more than likely the clips were broken off . Easy fix though .

 

[nube90]

No I havent replaced them yet I was going to do it tonight but the parts store was closed. I'll check the injector connections tommorow.Thanks.

 

[ROOKIE1]

Any little bit of help I can be , is just payback for what I have already received here myself . . Also if you are going to be up for a bit of reading . You need to check out vfaq.com . Lots of great info .

 

[nube90]

Ok update Ive figured out that the car dies out more when cold when hot it dosent do it has much also I replaced the plugs but it didnt do anything but havent replaced the wires also I dont think it has a BISS screw in it because the guy filled the hole with putty or something so ive been drilling into with my dremel but I havent ran into a screw yet so there may not be one in there and I dont want to drill all the way down if theres not one and sometimes the car will idle up to about 900rpms by itsself then go back down and when I rev it up while idling it really sounds like its going to die out (sputters really bad)