89 Audi 90 Fuel Problem
 

I have recently acquired this fine car. However it was negelected for 2 years and had not been running. After cleaning out the gas tank, replacing the fuel pump and fuel filter.. I attempted to start the car. I found no fuel was going go the injectors at all. None was coming out of the fuel distributor. I took off the distributor cleaned it the best I could.. NOW.. lol... the cylinders are filling with fuel.. How can I fix this. If anyone out there can help I would appreciate it. I have 3 days to get this car running as a gift to my fiance' for her birthday.. Please Help !!!!! lol

Steve

RE: 89 Audi 90 Fuel Problem
 

more investigation required,

does it spark at the plugs ( distributor cap/ rotor button/ rotor arm) spark amplifier/ crank/cam sensor

RE: 89 Audi 90 Fuel Problem
 

Oh ya It sparks fine.. originally I had the engine running with carb cleaner.... it runs good, was not getting fuel at all to injectors but now cylinders are filling with fuel to the point the engine will not crank. I have to remove the plugs and blow out the gas.

RE: 89 Audi 90 Fuel Problem
 

Yes, getting plenty of spark. cylinders are filling with fuel. I have to remove plugs and blow out fuel from cylinders

RE: 89 Audi 90 Fuel Problem
 

over fueling sounds about Right check the cylinder compression ratio and timing marks

RE: 89 Audi 90 Fuel Problem
 

I had the engine running quite smoothly by spraying fuel into the intake when the injectors were not getting fuel so the timing must be ok.. unless I am missing something.. what controls the fuel going to the injectors or what tells the injectors to open and allow fuel to pass? I am a little confused

RE: 89 Audi 90 Fuel Problem
 

Ah...leaking injectors or stuck plunger. This is a continuous injection system. It is controlled by air flow which moves a plunger up and down. Your plunger must be stuck in the up position. to fix it, you must pull off the fuel distributor (mounted on top of the air box). should be four flatheat bolts. when you pull it off do it carefull so as not to drop that plunger (VERY IMPORTANT NOT TO DAMAGE IT!). Then your goal is to get that plunger out if it is indeed stuck. A magnet might help. Whatever you do. Don't damage the plunger.

If it is not stuck then check that it moves freely and that the flapper (big metal plate) in the airbox moves as it should and closes properly.

The only other possibility is that the injectors are all leaking. Not likely but possible if some grit got into them either from the tank or if you cleaned them. Easy to replace but will cost you about $150. Look on autohousaz.com.


Frankie

RE: 89 Audi 90 Fuel Problem
 

Frankie,

Thank you so much.. I do believe that is the problem.. i have taken the top off to clean..the pin wont come out unless the screw is removed... it does not slide real easy but it does move.. how do I check the airbox to make sure it's working properly..

thank you in advance.. I might actually get this running this weekend.. and be able to give it to my fiance' :D

Steve

RE: 89 Audi 90 Fuel Problem
 

Interesting. I havn't actually taken one of these apart before. I dissassembled the same system that was in my vw rabbit. As far as I know there shouldn't be anything holding that plunger in once you've unbolted the distributor from the air box. Here is a picture...

http://www.ncr-pca.org/tech/tech-closeup.gif

The plunger is the thing in red.

Here is a better picture in which you can see how the airbox and distributor are different parts. The difference here is that we have 5 cylinders and that picture shows 4 cylinder version of that fuel system.

http://www.volvoclub.org.uk/graphics/jetronic.jpg

Frankie

RE: 89 Audi 90 Fuel Problem
 

Hmmm, I am going to work on it this morning. I do know that the plunger did not slide real easy. When I did remove the distributor and looked under it, there is a nut around the plunger and holding the plunger in is a screw with a hole in it for the plunger to stick through. This screw has to come out for the plunger to come out. I wonder why the difference. I am going to check it again and see if I can figure out how to test and see if the air box it working.