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Hey there guys. First time posting here in Audi World. I found this forum site while looking for more info on my recently purchased 1995 Audi 90q. I have been wanting to build one of these cars for quite some time now as I have always loved the old school turbo quattros. I eventually plan on a 20vt or 2.7stk swap, after I blow this 2.8 up in the snow with Nitrous My Stage 2 B5 will be going under the knife for some stage 3 upgrades this winter while I'm out driving the 90. (Frankenturbo F4h's, 734cc injectors, fuel pump, catless DP's, etc...) So here's the deal- I bought this 90 for very cheap off of an older gentleman. The car is solid. Has very little rust (I live in Maine, so that's a big deal around here...). In decent shape inside and out. Goes alright for being a 2.L8 (till I swap it ) The car had been sitting at the previous owners camp for the last year. Battery was dead, she fired right up after a jump and coughed a little smoke and all was good.
Heres the issue I am having. Car has no brakes right now at all. I tore apart all the calipers (new pads and rotors and calipers going on all around), and bled all the brakes as per normal procedure. Upon getting to the last brake to bleed (front passenger), I noticed no fluid coming out of the bleeder screw AT ALL. Reservoir was full, and no fluid was leaking out anywhere else. At first I figured it might be my master cylinder not pushing through enough fluid, I verified that the master cylinder was fine after removing the brake lines and testing for pressure through each fitting adapter. Pressure seemed to be all there. But I'm not 100% sure.
So, I have fluid that is not being pushed through to my front drivers side rear. Is there possibly still a lot of air in the line? I feel as though it should have been pushed out after the 9 million times I pressed on the brake pedal. No fluid is leaking from anywhere else. Pedal is not getting harder. Could it possibly have something to do with my ABS module? Does anyone know which line from the ABS mod goes to the drivers side front so I can try and blow it out in case something got stuck?
Any commonly know brake issues and solutions?
Anything other common issues that you guys know about? Thanks a lot!
Then you said" I verified that the master cylinder was fine after removing the brake lines and testing for pressure through each fitting adapter. Pressure seemed to be all there. But I'm not 100% sure." did you loosen the fittings at the wheel well, where the steel line connects to the flex hose?
I ask because if you are getting good pressure down at the flex hose..then odds are you should be getting pressure to the caliper too. Loosen the fitting (just loose enough to weep brake fluid) and see if there is a good amount of brake fluid when the brake pedal is used. Compare the results on the front passenger side with the other wheels.
Be sure and bleed the brakes starting with the wheel furthest from the master cylinder then go around. RR (Right Rear) then the LR then the RF then the Left Front..getting closer to the master as you work around the car. You may need to repeat several times
Be careful when manually bleeding the brakes with an old master cylinder. You can "blow out" the seals by pushing the brake pedal all the way to the floorboard over and over. The piston in the master cylinder is now traveling deeper in the bore and it can cause the rubber seals to stop sealing. There can be a worn "step" in the bore of the old master cylinder that will tear the seals. Put a wood block on the floorboard so the brake pedal travel is not going full sweep and pushing the piston too far into the bore.
That could be your problem.
Last edited by Rusty Spokes; 09-15-2017 at 02:53 PM.
Thanks for the reply Rusty Spokes. Upon further inspection of my brake system I came to the conclusion that the brake master cylinder was bad. Just ordered one online today. Should be here in about a week or so. In the mean time I have further inspected the vehicle and found that the blower motor is gone. Bummer Oh well! I'm hoping there is a short somewhere and that it will be an easy fix. I turn my temp on and my blower fan all the way up and nothing happens. I will further inspect the blower motor tomorrow to determine if that is the issue. Hoping that I can bypass the ECU and figure out a way to apply power to the fan manually to further determine my diagnosis.
If you have the manual style HVAC controls the vent fan controls are very simple. There is a resistor pack for the fan motor along with the fan motor itself behind the glove box. The fan motor is easy to change.
The fan motor is vulnerable to the elements due to its location. Leaves and water can get in there. You can retrofit a cabin filter holder part number 8A0819441A $35 from Audi if you find the motor full of junk. Install that and add a cabin filter to the holder. The fan part number 8A1820021 is about $55 from FCPeuro or $40 from Hansauto.
If you have the manual style HVAC controls the vent fan controls are very simple. There is a resistor pack for the fan motor along with the fan motor itself behind the glove box. The fan motor is easy to change.
The fan motor is vulnerable to the elements due to its location. Leaves and water can get in there. You can retrofit a cabin filter holder part number 8A0819441A $35 from Audi if you find the motor full of junk. Install that and add a cabin filter to the holder. The fan part number 8A1820021 is about $55 from FCPeuro or $40 from Hansauto.
If you have the manual style HVAC controls the vent fan controls are very simple. There is a resistor pack for the fan motor along with the fan motor itself behind the glove box. The fan motor is easy to change.
The fan motor is vulnerable to the elements due to its location. Leaves and water can get in there. You can retrofit a cabin filter holder part number 8A0819441A $35 from Audi if you find the motor full of junk. Install that and add a cabin filter to the holder. The fan part number 8A1820021 is about $55 from FCPeuro or $40 from Hansauto.
Rusty Spokes, these are the codes I received after putting the auto HVAC to "programming mode".
11.5 Center flap, static block Motor is cycled; software attempts to eliminate block
15.7 Back pressure flap, sporadic block
18.3 Fresh air blower voltage, sporadic
Am I supposed to try and change values of certain programming points to get it to work again or is this a part I should be replacing? Any ideas? Thanks again, bought this car as a winter beater and definitely going to have a hard time driving it without defrost >
Alright guys, so I figured out my issue with my blower motor not kicking on and wanted to share just in case anyone else is having similar issues.
Quick dianosis- (glove box already removed)
Remove black w/ blue stripe wire (positive) and brown wire (negative) from your blower motor
Turn key on, and turn fan all the way up on HVAC controls
Take a multimeter, set it to DC, and attach your positive lead to your black w/blue stripe connector and your negative to the brown wire that you removed from the blower motor. You should read roughly 12v (my case specifically read 11.8v). If you have your fan turned all the way on and you are not reading any voltage at these 2 connectors your issue is NOT your blower motor, your issue is within your HVAC controller or blower motor resistor.
Another way to diagnose-
Apply 12v to the pins on the back of the blower motor after you have removed the positive and negative leads. Remember, black w/blue stripe+positive (bigger more round hole around pin) and brown is your negative (smaller more oval shaped hole around pin). If your motor does not kick on when 12v is applied you have a bad blower motor.
However! If you have diagnosed the issue to be a bad blower motor using either method above, do not fret (yet)
Remove the 3 screws holding in the blower motor and pull off the blower motor. The actual blower motor itself needs to be pulled from the plastic casing. The motor is held into the casing by 3 rubber grommets. These grommets need to be pushed down while you pull the motor out. Yes, it comes out hard, and more than likely one of the grommets will go flying across the floor. After you have removed the motor from the plastic casing you will want to look at the back of the motor. You will see a bunch of copper wires and positive and negative soldering points.
NOW, you will see two springs perpendicular from each other on the back of the motor being held in by folded over copper flaps. Unfold these copper flaps and remove the springs. Take the spring and stretch it out and spray all the connectors on the back of the motor with contact cleaner. Give the motor a couple good spins and install springs back into copper sleeve and fold over the tabs again to hold springs back in place. Put everything back together and apply 12v again and see if she spins (make sure to put motor back in casing again before seeing if it works or you will rip your wires off of the pins or the back of the motor) If it now spins again congratulations, your motor will now work for another 1 day to 10 years or until you stop being a cheap **** like me and just go out and buy yourself a new one for $40
Yay more problems! Finally got the brakes sorted out. Thought I was finally golden after the few minor fixes I needed to do. Go to lower her back down and take her for her first real test drive, aaaaand, DOESNT START. Cranks and cranks but won't fire. I don't think it's getting any fuel. Any way for me to test if it's the fuel pump? Fuses are good. Can feel fuel pump relay clicking when having friend turn key. I read somewhere that these cars don't "prime" when you turn the key to accessory. Is this true? Help please
I would not be concerned with the system "priming"
Do look around the engine bay and be sure no plug connector were broken of loosened ..in particular the G40 camshaft position sensor on the drivers side..near the master cylinder. The plastic connector over time will become brittle and very easy to break.
Check that engine speed sensor too..it is down and safely out of the way but there is a gang of connectors on the firewall..and it is one of them. Be sure they are all connected.
If you want to check to see if your fuel system is working (insert the lawyer disclaimer here) you can with care..on the drivers side top side of the engine there is a fuel line that runs up to the fuel rail. Should be a pair of 17mm wrenches to remove the line..then put the line in a jar and have your shop assistant try and start the engine..avoiding any open flames and sparks..fuel should come out of the hose into the jar..it wont take long to see if your fuel pump is working.
09-14-2017, 06:29 PM
My First B4 (Common Issues?)
My Stage 2 B5 will be going under the knife for some stage 3 upgrades this winter while I'm out driving the 90. (Frankenturbo F4h's, 734cc injectors, fuel pump, catless DP's, etc...) So here's the deal- I bought this 90 for very cheap off of an older gentleman. The car is solid. Has very little rust (I live in Maine, so that's a big deal around here...). In decent shape inside and out. Goes alright for being a 2.L8 (till I swap it 
) The car had been sitting at the previous owners camp for the last year. Battery was dead, she fired right up after a jump and coughed a little smoke and all was good.
Oh well! I'm hoping there is a short somewhere and that it will be an easy fix. I turn my temp on and my blower fan all the way up and nothing happens. I will further inspect the blower motor tomorrow to determine if that is the issue. Hoping that I can bypass the ECU and figure out a way to apply power to the fan manually to further determine my diagnosis.
