1999 Jeep Cherokee turns over "very slow", shuts off when it idles

pinkbumblebee · #1 08-15-2007, 08:51 AM

1999 Jeep Cherokee turns over "very slow", shuts off when it idles--When you give it gas it keeps running but when it goes to idle, it stops running. We're thinking its maybe the battery, but not sure. Is there anyway of checking the battery without taking it to a shop? Like a testor of somekind. Could it be the alternator? If you can help us, we would appreciate it

Gary and Gayle
Gulfport, Mississippi

AlohaBra · #2 08-15-2007, 09:30 AM

Check for voltage. Use the gage on the dash if you have to. Better to use a digital one that you can use for other testing.

When cranking the voltage must stay above 9.6 volts at alll times.

pinkbumblebee · #3 08-15-2007, 10:16 PM

We went outside and checked the voltage meter. When he turned the key on, the meter doesnt move until it starts. When it started it went up to about 12. As soon as we let off the gas, it stalls out.

pinkbumblebee · #4 08-15-2007, 10:16 PM

We went outside and checked the voltage meter. When he turned the key on, the meter doesnt move until it starts. When it started it went up to about 12. As soon as we let off the gas, it stalls out.

dave92cherokee · #5 08-15-2007, 11:44 PM

Do a search on here and check out how to test your CPS (crankshaft position sensor) there seems to be a rash of those going bad in the 95-2000 ranges lately. Also check vacuum lines on the intake manifold to make sure none are damaged or disconnected and look inside the throttle body to see if it's gunked up. Might just need a slight adjustment to the idle screw or possibly a bad IAC (idle air controller).

pinkbumblebee · #6 08-18-2007, 10:43 AM

Now the Jeep starts (still cranking over slow) but wont stay running unless you keep your foot on the gas. As soon as you take your foot off the gas, it will die.

AlohaBra · #7 08-18-2007, 11:51 AM

Now would be the time to check for fuel pressure and intake leaks.

Make sure all hoses on the intake are in good condition and not cracked.

SirXJ · #8 08-19-2007, 07:18 PM

I had an idle problem like that. Turned out to be the IAC.

Doesn't explain the problem starting, but I'm just sayin'

longfellow · #9 08-20-2007, 08:14 PM

If she wont start with headlights on. Then I believe its the battery.If it starts and wont stay running could be battery or voltage regulater bad.
check battery with a multimeter as is, should read 13 vlt range. Also clean battery post and cable connections.

pinkbumblebee · #10 09-02-2007, 10:55 PM

Update on this Jeep that I want to drive over a cliff.

We have an appointment to take it to a dealer. We did put a new battery on it, but that wasnt the problem. So we go out this morning and start it, and it started great and didnt die out when idleing.. Now does that make any since? Its so unpredictable!!! Any clue why this kind of behavior anyone?

Thanks everyone

Saudade · #11 09-02-2007, 11:18 PM

Check your battery cables and grounds. On the cables, peel back a bit of the insulation near the battery terminals and see if they're corroded.

reekor · #12 09-03-2007, 08:41 AM

My 96 does the same thing if the battery has been disconnected for few hours. It will not start unless you keep your foot on the gas and it needs to be held their for a few minutes then it will die once foot is removed from gas and once restarted all is fine. I found it a little weird that it would do this, so I plugged in my scan tool to see what was going on, and managed to recreate this problem by clearing the IAC memory. My best guess is that after the battery has been disconnected for a while the PCM loses memory of the IAC position and needs to relearn it.

Quote:

Originally Posted by pinkbumblebee

Update on this Jeep that I want to drive over a cliff.

We have an appointment to take it to a dealer. We did put a new battery on it, but that wasnt the problem. So we go out this morning and start it, and it started great and didnt die out when idleing.. Now does that make any since? Its so unpredictable!!! Any clue why this kind of behavior anyone?

Thanks everyone

pinkbumblebee · #13 09-07-2007, 07:04 AM

Quote:

Originally Posted by reekor

I found it a little weird that it would do this, so I plugged in my scan tool to see what was going on, and managed to recreate this problem by clearing the IAC memory. My best guess is that after the battery has been disconnected for a while the PCM loses memory of the IAC position and needs to relearn it.

We decide to not take the jeep over to the dealership because it's running good RIGHT NOW!. Maybe what you described above is what's going on. We did put a new battery on it and took it a week or longer to start running good again. I hope this is all that's wrong THIS TIME!!runaround

sswpriz · #14 10-06-2007, 07:37 AM

I had the same exact problem with my 99 cherokee with 96K miles.
Took it in to have it tuned up, first since new, and then also put in a new battery, the dealer told me that it was only pushing out 120 CCA, and that seems to have fixed my problem. They also said that my plug wires were falling apart in the techs hands as he was taking them off, I have them, they were pretty bad.

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