Nicholas Granfors

I got my uncles 1990 coupe quattro 20v 2.3 5cyl and I want to restore it too great working order.

I would love some ideas of what to diagnose first. I've heard that the fuel pump when warm can result in hesitation. Yet my car is running rich...I hope it isn't a piston seal.

I have some main issues
- Car has hesitation when it is warm outside (runs great in morning on my way to work.)
-brake lights will not come on.(new bulbs, very touchy)
-Very bad gas mileage something like 13.4 on a good highway tank.
-brake won't go all the way down when applied sometimes.

What I've done.
-replaced rotor cap and rotor head
-new muffler and exhaust.
-Fluid flush oil, and coolant.
-cleaned ICV
-new brakes and rotors

List to do after main problems are solved.
-tie rod assembly
-ICU unit
-oxygen sensor (no clue on how to replace)
-replacing vacuum tubing
-replace coolant, power steering

CRAZY_RUSSIAN

whats a piston seal?

have you flushed your brakes?
sounds like you got a vacuum leak and some other problems, have you tried pulling your codes?

Nicholas Granfors

I'm not sure how or where to pull the codes? People always talk about but I don't understand where I pull it or what I use. I've looked on 20v.org and saw the VGA they used looked something similar to a.c. d.c. circuit master 90-300v.

Checked around for a lot of the Vacuum leaks, not sure what type and size hosing to use? Lines are old and need to be replaced.

Nicholas Granfors

Code reader?

kennedyanyanwu

Assuming you have done a compression test and its good. the Brake issue might b tied with the hesitation or missfire by way of vaccume leak. A leak that bad should be very audible with the engine running. as for checking codes you most likely have the DLC connectors under the driver side dash, above the pedals. connect a jumper wire between both pins for 4 secs and remove it, watch CL blink the codes, you might have to do it for it each code.


Under driver dash or in fuse box under the hood as in 3rd pic




You could have this style aswell but less likely. If u do the your Fuel pump relay will have a slot for a fuse. Insert a fuse for 4 secs and remove to flash each code.




This is the B4 90Q fuse box with DLC in it, pin C&D....

Nicholas Granfors

I'm not sure what I'm supposed to connect my VAG to read the codes. I know it isn't in the fuse box under the hood. This is a picture of under my driverside wiring. Have no idea where to start. Looked around for the black and brown connectors and found nothing.

Nicholas Granfors

I'm completely lost guys. I've been looking around under the wheel for a couple hrs now. Can someone provide an exact picture of what the connection looks like?

varia

keep looking. the 3 connectors should be there somewhere

bradwilcox

Bad gas mileage: ensure the ECU-associated fuses are there and good; ensure all fuses are there and good, even the spares.