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-   -   91 YJ long start problem (http://www.wranglerforum.com/f218/91-yj-long-start-problem-258691.html)

Bgaeta84 07-27-2013 02:30 PM

91 YJ long start problem
 
My 91 4.0 automatic yj has been having a hard time starting. It's isn't temperature specific. It will start but just seems to have a real hard time doing so. When I first turn it over, it will just crank and crank. Then, shake as though it is trying to start. Sometime it does and I just release the ignition. Other times, it wont when I release the ignition. Once it starts, it runs great. I have replaced crank shaft position sensor, throttle position sensor, fuel pump, fuel filter and had vacuum lines cleaned out.

Three mechanics later, no luck. Can anyone help with this!?! I would be so grateful! Also, any referrals for Jeep mechanics in the baltimore area? I would like to fix this on my own but am willing to go to a mechanic if there is a good one out there for such an issue.

Any help is appreciated!

PaulRevere1991 07-27-2013 03:07 PM

Battery?

Bgaeta84 07-27-2013 11:19 PM

It has a strong crank so I didn't suspect the battery. Would it not have a slow crank if it were that?

AllMudd 07-28-2013 12:49 AM

How strong an constant is the spark? How old and dirty are the cap and rotor as well as your plugs?

Bgaeta84 07-28-2013 08:40 AM

The plugs,wires and distributer were replaced about 5000 miles ago...and they look new....I'm not sure how to measure the strength and consistency but it cranks at what sounds like a strong and normal speed. it almost sounds like a carb engine when it is starting....you know how you have to pump the gas a couple of times to get it started. Except this is injected...

Thank y'all for your help and ideas! I'm at my wits end with this.

bajajohn 07-28-2013 11:22 AM

My 91 4.0 never starts on the first crank. I release the switch and try again and it fires right up. I have been thinking the starter may need a rebuild.

Bgaeta84 07-28-2013 03:54 PM

So I just had advanced auto parts run checks and they said my battery, starter and alternator are all working great. They said it could be the ignition cylinder? Does anyone know if that sounds right?

@bajajohn- I have tried that too but it reacts the same no matter how many times I release...advanced did that check for free...maybe they cold tell you if it does needs to be built.

Mattador1516 07-28-2013 05:13 PM

Check the coil. Mine did the EXACT same thing. I checked everything in the ignition system. Troubleshot it down to the coil. Sure enough, when I removed the retrograde, it was cracked (out of sight). Replaced it and works great now.

bajajohn 07-28-2013 09:56 PM

Quote:

Originally Posted by Bgaeta84 (Post 4012779)
So I just had advanced auto parts run checks and they said my battery, starter and alternator are all working great. They said it could be the ignition cylinder? Does anyone know if that sounds right?

@bajajohn- I have tried that too but it reacts the same no matter how many times I release...advanced did that check for free...maybe they cold tell you if it does needs to be built.


I am lucky I live in Ensenada Baja Mx. we have shops here that actually rebuild things for a fraction of the cost to replace and they are really good at diagnosing the problem,

Bgaeta84 07-29-2013 10:12 AM

Wish I had something like that here...everyone I have gone to so far has been miles from being that good.

Boystaysin 07-30-2013 12:46 PM

Quote:

Originally Posted by Mattador1516 (Post 4012960)
Check the coil. Mine did the EXACT same thing. I checked everything in the ignition system. Troubleshot it down to the coil. Sure enough, when I removed the retrograde, it was cracked (out of sight). Replaced it and works great now.

I agree. I had a similar issue and turns out it was the coil as well as the connectors on it.

harleydragon 07-30-2013 12:49 PM

fuel pressure regulator

Bgaeta84 08-02-2013 11:09 PM

It was the fuel pressure regulator, bad fuel pump (i had just installed it)and leaking o-rings on fuel injectors 3,5, and 6...my reverse lights had stopped workings for was the reverse switch other threads had mentioned! Thanks all for your help!

Bgaeta84 08-02-2013 11:11 PM

Btw, found a killer shop here in Baltimore called Baltimore Body Shop. In case anyone else reads this thread and needs work done...ask for Tom. These peeps were awesome!


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