CEL codes 12, 15, 13, 13 - Idle stumbling issue

1992 Cherokee, 4.0L HO, Auto trans.

I pulled the motor about a month ago when the PO broke off all 3 passenger side motor mount bolts in the block. We put it back in and it has been giving me issues ever since.

When it's first started, it idles fairly low. Sometimes when coming to a stop when cold, it will stall. Kind of makes me think it's not a vacuum leak.

Other times, it will idle low, then when the light turns green, and the throttle is depressed, nothing happens. I have to modulate the throttle to get the thing to move. after it gets over ~1500, it's fine.

Coolant gauge isn't reading after the swap. Replaced the sensor at the rear of the head, but it's still not reading. Could be wiring?

I know my speed sensor doesn't work, and that the battery has been unplugged.

Why am I getting two 13 codes? I'll be cleaning out the TB IAC and MAP sensor connectors tonight, maybe that will help.

Thanks for the help.

Good question on the 13-13, there are two 13 codes listed on 5-90's website: http://www.kelleyswip.com/obd1.html

But one of those codes says no change in MAP from start to run, so you need to test the MAP and its harness between the sensor and the PCM.

Good luck.

Thanks so much!

I'll tear into it tonight and update tomorrow or this evening.

:twak:

The MAP sensor had no vacuum reference. I'm not sure how I was driving this thing around without more trouble.

The Jeep runs beautifully now.

Glad you found it!

Now, go have some fun!

joe_peters said:

Glad you found it!

Now, go have some fun!

Click to expand...

For sure 8)