No fuel pressure
Asked by xshuey May 08, 2012 at 11:05 AM about the 1991 Volkswagen Jetta GLI 16V FWD
Question type: Maintenance & Repair
I have a 1991 VW Jetta 2.0 16v . I just bought it from a friend . It has been sitting for a while. After charging the battery when I turn the key on I can hear the fuel pump in the gas tank run for a few seconds. but it won,t start .The gas is good. I have no fuel pressure at the fuel filter back by the tank. Or up at the front of the car anywhere. Anybody have any ideas what might be wrong? have a Bently manual coming.
7 Answers
Is all the electrics good? The pump will make noise for few secs and then it will go slightly quieter, it could be a bad connection on it too, but I would check spark plugs&cablez, coil etc. maybe bad immobilizer?
Thanks, but I can get it to run if I give it a small shot of ether ,I know not too much cause you can blow a head gasket. It just isn't getting fuel. What is this immobilizer? And where is it?
I don't think jetta's had immobilisers in 1991
I don"t know either. Still waiting on my Bentley manual
the pump itself is in the boot, under the black round cover, if it makes noise after u turn ignition on it should be fine, check the connections on it. If u can smell gasoline out of the exhaust when u trying to start her up its 100% electric if not than check the pump, fuel lines, throttle body (the tend to get stuck sometimes), could be a clog somwhere (maybe fuel filter needs changing). Don't use ether or u might mess it up even worse. I would maybe tow it and try start it with 2nd gear if this doesn't get her moving than could be that the pump died but since u said it does make some noise... Immobilizer is a device that cuts off electrics from the car and you would have no spark, not quite sure where it was hidden. Hope this helps, mine does that too from time to time but it starts in the end but no apparent reason for it
^^ These cars have two pumps and while the auxiliary in the tank may be running, the main fuel pump located under the vehicle is most likely not, this not allowing pressurized fuel to flow all the way up to the rail. Put rear of car on jack stands and engage pumps via jumper on fuse block 30 location and Z1 I believe. When you hear pump running get under vehicle and feel main pump underneath to see if it is running. If not, unplug it and apply multimeter across plug connections from harness and if you show 12-12.5v you have a bad main fuel pump. Wala. Doing simple electric system diagnostics will 99% of the time save you valuable time and keep you from throwing $$ at the problem. I know this is 2 years late but it might help someone else looking for some answers.