Long crank times/hard start

MARKYZ

MEMBER
1999 JEEP CHEROKEE
6 CYL
4WD
AUTOMATIC
199,000 MILES

I am having some issues starting it while cold or when it's been sitting for over an hour.

When I turn the key it cranks, and cranks, and cranks some more and then eventually starts. After it starts it runs perfectly fine with no issues or hesitation.

If I turn it off for 15 minutes while I run inside the coffee shop and come right back out it starts no problem. But if I leave it for over an hour it's the same story.

6 Replies

SERVICE WRITER

MECHANIC
9,123 POSTS

This sounds like a fuel pump bleeding down. Try cycling the key as a preliminary test:

When you are expecting the problem to happen, turn the key to the on position without cranking the starter. After 5 seconds. Turn the key off. Repeat this 3 times. This will command the fuel pump to push fuel into the lines, (even though it should be there).

Then crank it.
If it starts first try, you are probably looking at a fuel pump.

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Wednesday, July 2nd, 2008 AT 5:32 AM

MARKYZ

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39 POSTS

What is the probability that this is related to the Crankshaft Position Sensor?

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Wednesday, July 2nd, 2008 AT 5:54 AM

MERLIN2021

MECHANIC
17,250 POSTS

If you are not getting misfire codes, it is remotely possible, do what SW suggested, it's an easy enough test.

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Wednesday, July 2nd, 2008 AT 7:06 AM

MARKYZ

MEMBER
39 POSTS

I did the test, the crank times significantly shortened. I put the key into the "on" position 8 times rather then 5 and she cranked like there was no issue. I already have a spare fuel pump since they are known to die on my model, however I didn't know that this was the symptoms of fuel pump failure. Thanks guys I appreciate it!

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Wednesday, July 2nd, 2008 AT 8:44 PM

PAUL KESSLER

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1 POST

Merlin2021, what is your suggestion if it does throw a misfire code? Mine throws a cylinder three misfire.

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Tuesday, November 24th, 2020 AT 10:20 AM

KASEKENNY

MECHANIC
18,907 POSTS

This post is from over 10 years ago so I doubt they will respond. However, here are some guides we need to start with if you have a misfire. If you have a long crank issue with the misfire then we need to start with a compression check and then swapping the injector and spark plug to another cylinder one at a time and see if the misfire moves with one of them.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Here is a guide on compression tests that I would suggest we need to start with just to make sure it is correct:

https://www.2carpros.com/articles/how-to-test-engine-compression

If it is move onto the injector as I suspect that is leaking causing the long crank and the misfire. You can pull the plug out and see if it looks fouled then that would be another indicator of a leaking injector.

Let's run through this and go from there. Thanks

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