Hi,

I'm new so be easy on me. I've owned my 93 Jeep Grand Cherokee since new and it's been good to me except the last few winters.

When it goes below 32 degree's it is VERY rought to start. It won't idle and I have to keep my foot on the gas to keep RPM's above 3000 until 'something' warms up. Even when the temp gets up there, it STILL takes a little while for it to run smooth. If I try to move, it just stalls, so I can't drive to make it warm up faster. Trying to go in reverse seems even worse. Once, what ever it is warms up, the thing purrs. Same as if temp is above 32.

I've had it in 2 shops. One dealer, one not. At a cost of $600.00 a whack for the last 2 winters. Neither of them could figure it out before the warm weather came.

Here's what I've done;

Plugs
Wires
Distributor
MCU - Motor Control Unit Black Box for $280.00 (dealer wanted to do it for $700.00)

I have no Idea what to look for now. In the shops it runs great. Or over 32 degrees.

Any Ideas would be greatly appreciated. I've spent too many days in the cold trying to figure this out and I don't want to do it again THIS winter.

I love my Jeep, it's been good to me *knock on wood* except for this problem.


Thanks in Advance.

If it has a heated oxygen sensor the heating coil in it might be bad.

Wow. Thanks for the reply. That could be it, I will try that next!!!

Thanks again!!

I just wanted to post the solution (for me) in case anyone else has this issue.

As suggested I replaced the Oxygen Sensor but while picking up the part I asked to see all sensors and found a temperature Sensor, which was under ten buck, so I got that as well.

It turned out the temperature sensor had a crack in it and has been the part causing me 3 winters of ......

AH, It finally Idles cold.

Bad oxygen sensors have nothing to do with cold starting.

If it has a heated oxygen sensor the heating coil in it might be bad.