tobtech

I have a 1998 Cherokee and when I go to start the Jeep after it has been sitting for at least a few hours it will not start on the first attempt, ever.

I crank it once with the key and it just cranks, then shut the key off and turn the ignition back on and crank a second time it starts right up. From then on it will start first crank until it sits again for several hours and cools down.

It is not intermittent, I can always count on it that the first attempt in the morning it will not start. It does not even sounds like it tries to start. It is like there is a kill switch on the ignition circuit. After the first time, I can drive around all morning and run errands, etc and it will start first attempt after that everytime.

It just recently started doing this. Does anyone have any ideas or have run into the same problem?

Thanks,

Cherryokee

If you search the forum on the topic of fuel injection and/or fuel pressure you will find similar discussions. Your issue has something to do with pressure in the fuel rail bleeding down over time (after having been off for several hours) and it relates to some kind of check valve.

stormitecture

Agree here, I have the same issue, but have only read some, no attempt to fix. Because if other issues with my motor, waiting to just do it all at once.

What is the longest time from a cold start that you turned the car on, but didn't crank it right away? I have done upto four minutes, but really doesn't make a difference. Of course mine does, on occassion start the first time. Sometimes it starts the first time, but it starts with a weak pressure and I most often shut it off then restart it. Sometimes I rec the engine, but that is when I am not thinking...and in a rush!

Cherryokee

Patience is important with this issue.

When you start, turn key to on position then wait 3 seconds (one mississippi, two mississippi, three mississippi) then turn key to ignition. During your delay, you (sometimes) will hear the fuel pump as it pressurizes the system. There is a method for checking fuel rail pressure, and it is rather simple, but I'm at work and cannot refer to my manual. Pressure should not bleed off too quickly (or at all, but not 100% certain about that). It's just that my '99 never had this issue - knock wood.

jomps

its probably the regulator in the fuel tank not holding pressure, after a few hours or overnight check pressure at fuel bar on intake, if its a weak spray or hissing air chances is your pressure regulator is failing/malfunctioning...if you get a new assembly dont buy airtex whatsoever

Jdherko2588

You have to let the fuel pump prime before you turn the key all the way over, Same problem, its a jeep thing,.. I mean MFI thing

nowhereman98

My friends 99 has the same problem. So we put a new chrysler fuel pump module in witch includes the check valve and filter/regulator and it still wont start without keying the ignition two times. The chrysler manual says to do a leak down pressure test with special tool 6539 to isolate the fuel pump or the fuel injector rail. My friend did not want to spend more money chasing this problem but I think one injector is leaking down his fuel system. I think it could be one of these three things .The check valve or regulator in the pump module or a fuel injector. Hope this helps and I hope to see more info on this problem.

jomps

yeah it could def be a leaky injector

tobtech

Thanks for all of the advice. I will look into these things. The odd thing is that the check engine light has not come on.

ETexas XJ

Fuel pump not holding pressure. Common problem, easy fix.

A leaky injector will give you a small puff of black smoke on start and you will be able to smell it easily.

Low pressure on first key cycle won't set a code.

If key on, key off, key on then start works then put a pump in it.

Cherryokee

Good stuff all. Bottom line is measure twice cut once. Doing the pressure tests to isolate the problem can (or will) save you some cashola in the long run.

tobtech

So if I understand correctly, first look for a leaky injector and if I find one, replace. If no leaky injector, then replace fuel pump?

This morning I tried waiting 10 seconds with the ignition on before cranking. It still did not start. Next crank, started right up. So waiting for pressure to build did not work.

Cherryokee

Did you hear fuel pump "whine" during that 10 second waiting period?

nowhereman98

If I were you I would buy one injector and keep switching it out and hope to find a bad one before you buy a fuel pump module.It might be a lot of work but its cheaper than the pump module.

tobtech

I did not hear the fuel pump but I don't ever recall hearing the fuel pump in this car. I have had other cars where I can hear it.