I recently bought a 1998 Jeep Grand Cherokee Limited V8. It sat for 2 years, and it obviously has some issues. I did the normal get up and go stuff. dropped and drained the fuel tank to clean it out. replaced fuel pump strainer, new battery. new oil filter, radiator flush and new coolant. fired it up first try and was feeling pretty proud of myself. but after the couple gallons of gas i put in to get things moving were gone it wouldn't start. I added more fuel and still no start. It will crank fine and turn over, but die immediately after. I started reading forums. I pulled the coil off the distributor and installed a plug to make sure I had spark. I do. I tested the fuel rail to make sure I had fuel pressure, I do. swapped the fuel pump relay and ASD relay, no help. and judging by what I've read, I don't think its the crank position sensor because the symptoms are different. I have absolutely no Idea where to go from here. please help a lowly jeep newbie.

 

Welcome to CF!

If it will start and run for a second or two, then die, it sounds like you've activated the security system somehow. Either that or the fuel filter is clogged with fine debris from the tank. IDK if that jeep has a remote filter outside the tank or not, but check that out.

 

It doesn't really run for a second or 2, it cranks, and you can hear it roar like its turning over, but it never actually runs. There's no fuel filter in line, there is a fuel pressure regulator on top of the fuel pump. But I haven't actually tracked down a filter yet. If there is a security system issue, how would one go about resolving it? It came with a key chain remote, but I don't know that it works or not.

 

IDK...I've heard stuff like lock and unlock the driver's door with the key a couple of times, but I really don't know. Or the hatch...whatever.

 

One thing I didn't mention, I had it running for a day or 2, but the rear hatch was stuck shut so I got it open by manually pulling the rod, and I disconnected the rod from the lock so it couldn't stick again. Could that have interfered with the security system?

 

I know for a fact the hatch lock is all jammed up. It won't turn at all. But the doors I guess would be worth a shot.

 

Possibly....There are hidden switches throughout the jeep for stuff like that.

My WJ will set the alarm automatically if all the doors are locked manually and the key is not in the ignition. It thinks it knows better than I do.

 

Would there be an indicator that it was a security system issue. A lot of the things I read said there would be a clicking behind the glove box, or a faint flash in the lights. And I don't have either of those. After it wouldn't start the first time I fiddled with the relays and it ran, but then after sitting a day or 2 it went back to not starting. So it's very intermittent. I just have no idea where to begin.

 

If you google 1998 Grand Cherokee security you will get pages of info on how to check and disable your security system if you have one. I just went through this on my 93 and no more problems.

 

What did you end up doing to delete the security system?

 

HAH to turn off the alarm...., you must turn the key to the right in the driver door twice, then go to the hatch and turn the key twice to the right, then its disabled.

 

That will be a problem. The hatch lock is all jammed up. The key only hoes in about half way, and it doesn't turn.

 

I have ruled out the security system. I disabled it via the infamous purple/yellow wire. Still the same symptoms. I have a suspicion that the ECM is the problem. I did a wiggle test, and it still wouldn't start, but it looks very poorly. It's all corroded up and looks like its having a bad day.

 

OMG! I think you are right! You should start by pulling those plugs and checking for corrosion inside them. Also check the BACK side of the plugs where the wires connect to the pins. Some of the sensor inputs are only 5 volts or less, so good clean connections are critical. I'd start by cleaning the outside with a household spray cleaner to get the dirt and crap off before you start removing the plugs. Also, check the plugs on other sensors like the MAP and throttle position sensor.

 

I actually took it off entirely after blowing the dirt off of it. The casing is very corroded. The "caulk they used to seal it was all dry rotted and turning to dust. I took the case apart, and found the same junk inside. Cleaned it out with air duster, and hooked it back up. Fired with no issue 5 times in a row. Put it back together and sealed it with black RTV. Not the best thing probably, but it's what I had. I plan on ordering one next Friday, so it only has to last a week. Lol