4 Wheel Drive/SUVs: 89 jeep cherokee 4L auto, harbor freight tools, jeep cherokee


Question
QUESTION: The other day I was driving and while I was pressing on the gas peddle I wasn't getting any response, there was gas in the tank, the battrey was fine, and the engine wasn't reving while I stepped on the peddle so I figured it couldn't be the trany, however I thought maybe it was the fule pump. I changed the fuel pump and still nothing. It will turn over when I turn the key but It will not fire up? I've tried so many times that the battrey is now dead.

ANSWER: Aaron,

This could be several things.  Before you changed the fuel pump, you should have checked to see if the problem is electrical, or mechanical first.

One of the first things you needed to do, was to check the fuel rail to see if you had the proper fuel pressure.  This would have saved you a bunch if you had the proper pressure at the rail.  You can purchase an inexpensive fuel pressure testor at Harbor Freight Tools.

The next thing you need to do is to find out if you have power at the spark plugs.  If not, then you need to check out the distributor cap, rotor, plugs and plug wires.  If these all are ok, then you need to check the ignition coil.

From there, if all seems ok, then you could have any one of several sensors bad, or a bad computer.

If you changed out the fuel pump yourself, then you must have some mehanical ability, so I'm assuming you want to try to find the problem yourself.  If this is the case, then you need to purchase a repair manual from one of your local auto parts stores.  There are 2 major brands.  One is Haynes, and the other is Chiltons.  They cost around $20, and are a must have item if you plan on doing any work, or troubleshooting yourself.

They give you step by step instructions for repair, along with pictures of many of the steps you need to take for a specific test or repair.

Also, you should buy a good battery charger, possibly one with a 200 amp starting circuit.

Carl

---------- FOLLOW-UP ----------

QUESTION: Prier to this happening I had been driving without a gas cap for a few week, so I would asume that would some how effect the fuel pressure in the tank. I bought a gas cap with the fuel pump. If it were the fuel pressure how would I fix it?

Answer
Aaron,

Normally low fuel pressure would be due to a bad fuel pump.  In your case, I would guess that you got some dirt in the fuel tank due to running without the gas cap.

Your next step, is to replace the fuel filter.  It's a good chance that it is plugged due to dirt in the fuel.

Carl