View Full Version : Problem after tune up.


cyberunlimited
05-12-04, 08:44 PM
Hello, I have a problem with my 1999 4.0 TJ. I replaced the plugs, plug wires, rotor and distributer cap. Now, it has a hard time starting. It has to turn over several times before it will start. Once it starts it runs fine. I believe that I have the firing order correct. I have 24000 Miles on it. Does anyone have an idea of what can cause this? Thanks.

Dukes69
05-12-04, 09:49 PM
If you have the firing order wrong, you will know! Check to make sure all the wires are pushed down on the cap and plugs. Check for water or junk in the distributor cap and that the cap is tight. Even though the plugs are pregapped, you might want to check them anyway. It actually sounds like a fuel problem to me . . . did it do this before the tune up?

cyberunlimited
05-12-04, 10:26 PM
There is a chance that water made its way into my fuel tank. Since then I have added additives to remove any water and fueled back up from a 1/2 a tank. It might be running better now. The problem seemed to start after the tune up, maybe not. Its strange that it will run great after it gets going, but have a problem starting, even after its warm.

Dukes69
05-12-04, 10:37 PM
how many second would you say does it take to start?

JeepJunkie
05-12-04, 10:50 PM
Crappy Starter Perhaps?

peteyg
05-13-04, 10:10 AM
The 4.0 TJ has a problem with injectors that leak down. You are probably flooded. This has nothing to do with milage and everything to do with age. You might want to replace your injectors. Just a thought...

cyberunlimited
05-13-04, 09:07 PM
It turns over fine, its not the starter. What is strange is if I try to start it for a couple of seconds, disingage the starter, and then try again it will start right up.

I can see that if the problem was when it was sitting, but I can drive it for a couple hours, turn it off, and it will take several turns to get it started again. That doesn't sound like flooding.

Dukes69
05-13-04, 10:08 PM
peteyg is right, I think. I just saw this problem on a 99 chevy truck. Same symtoms. What was happening was the fuel lines were loosing pressure and took a long time to start. Basically the fuel system is loosing pressure, somewhere . . . its either draining back into the tank or through the injectors.

cyberunlimited
05-14-04, 09:42 PM
Excellent, now we are getting somewhere. I'll try just turning the key to the power position and maybe pressurizing the system and then try turning it over. Either way I'll check the whole system for leaks.

rick
05-15-04, 02:20 AM
Isn't hard starting also symptomatic of a failing CPS? I think it usually pretty bad once the CPS starts to go, but just a thought.

cyberunlimited
05-16-04, 04:44 PM
I checked the fuel line pressure prior to starting it and it doesn't seem to pressurize the fuel system when I turn the key on. Isn't it supposed to turn on the pump when you turn the key to the power position? If it doesn't do that, how can it ever start, although it does start after turning the engine over several times. I could understant it if it was a carburator system with a mechanical pump, but not with EFI.

rick
05-16-04, 11:58 PM
Well, seems like dukes said, the injectors (or something else) are leaking down or the pump is going...

gteasdale
05-22-04, 09:48 PM
I had a simliar problem with my 99 grand cherokee. The dealer rebuilt the fuel pump (located in the gas tank) and everything was better.