[Megs1082]

Hey guys. My wife's 1993 Jimmy is having similar issues.

It developed over the course of a month or so from easy to start to hard to start. Now in order to get it to start you have to try for a couple minutes or hook it up to an external secondary car battery through jumper cables to get it to start.

I've replaced the plugs, checked the wires, changed the distributer cap, changed the fuel filter, and checked all the fluids before I really started getting concerned.

I bought a fuel pressure guage and hooked it up to the schrader valve. The pump hits 60ish and then - SOMETIMES drops off to below 50 and sometimes holds at 55. When the car is running it runs fine.

I've had the alternator, batter, and starter all checked out at autozone - they are all good. I would think this was a weak battery because of the fact that whenever I hook up a set of cables it will start in the first or second time. However - yesterday I swapped a 900 cranking amp battery from my Grand Prix into her Jimmy and put her 700 cranking amp battery in my Grand prix. The same problem stayed with the Jimmy even with the switched batteries. Now here's the odd part. Connect them via jumper cables and whalla ! instant start. The voltage doesn't change on the jimmy's guage when I connect the two? It just doesn't make sense.

After reading this thread it looks like it could be several things. The problem is that it seems very intermittent. The fuel pressure drops sometimes, doens't drop other times. The one key thing is that once it starts one time....It will start easily until it gets cold again - which makes me think it must be some sort of relay somewhere?????

I read in teh chilton's manual that the fuel pump relay may need to be changed. But I don't know where that is???? It says in the convieniece center in the middle of the dash but I see no such thing??? Any ideas? Things next to try - I don't know what much else to do here????