1996 Pontiac Grand Am



May, 21, 2013 AT 10:13 AM

First thought fuel pump was bad. Wasnt. Then got car started and while driving it would act like it quit firing on 3 cylinders n wouldnt run over 20 mph. Then drove to work when I went to leave it wouldnt turn over. Tried to load in trailer and wont shift from park. Had battery tested and it is fine. So r my fuses. Any help u can give wiuld b greatly appreciated


1 Answer


Ernest Clark

June, 11, 2013 AT 12:15 PM

First, what made you believe fuel pump was bad, and how didn't you find out it wasn't. Whatever tests you may have already don't will help me narrow down possible causes.
Also, are there any warning lights on the dash, specifically the check engine light? If so, that is where you should begin because having the computer scanned will point you in the right direction.
There are several possible causes for your car to run rough/misfire. It could be as simple as bad gas to as complicated as an ECU malfunction. If there's no trouble codes stored in your computer, begin your diagnosis with by checking that there's no water in the gas. Next check the basics like the spark plugs, air/fuel filters, etc.
If all of those are new, then you'll need to check that fuel pressure is good and that the ignition system is in good shape.
The fuel system consists of the pump, filter, regulator, lines, injectors and wiring/connectors. Check each component thoroughly.
The ignition system consists of the coils, spark plugs/wires and wiring/connectors.
Don't forget the ECU and sensors which tell control both systems. If a crank/cam sensor is faulty, you'll have a random misfire that will cause the symptoms you described as well.

Please login or register to post a reply.

Battery Replacement
Battery Replacement Guide
Starter Motor Replacement Ford Mustang
Battery Replacement Honda Civic 2006-2011
Starter Replacement
Battery Replacement Ford Contour 1996-2000