Engine stumbling at Idle?

[IN2FORD]

If I am sitting at a stop light at idle, once I am there for a minute or two, there is a good chance that the engine will stumble or even die. I checked for codes but found no problems. Any ideas? Could it be the IAC but not set any codes? It has been cleaned a month or two ago.

 

[JayTye4k]

I totally understand

Man, I'm having the exact same problems. Replaced IAC Valve, Spark Plugs, Wires, Air Filter, Fuel Filter, Added Seafoam to intake system and gas tank to NO avail. I also have a 95XLT so let me know when you determine what is causing the problem and I'll do the same. Someone mentioned cleaning the MAF sensor, but I'm not sure how that works...Anyhow, Good luck with yours. I hope I find out what's causing this soon because it's driving me INSANE!!

Jay

 

[stubborn1]

I would start by cleaning both the IAC and the MAF. When is the last time you changed the spark plugs and wires?

 

[IN2FORD]

Within the last 3000 miles, I have change plugs, wires, oil, trans fluid, passenger side O2 sensor, TPS sensor, and ran seafoam through. I have no ideas left....

 

[aldive]

I think running another can of Sea Foam through the motor would be wise.

 

[IN2FORD]

Bump-

I still have not figured this out yet. Anyone else with ideas or fixes on this.

 

[albrosm]

stumble

I have the same problem, i was told to try and replace the temp sending unit, i would of never thought in a million years that would affect it but it was telling the computer, that it was always cold, seemed to fix my problem.

 

[JayTye4k]

What is this temp sending unit that you speak of, and where can I find this thing?

 

[TPLYNCH]

It's the sensor that tells the ECU what temp your engine is running. It is near the thermostat I believe. Run a search on it and read what comes up...

 

[JayTye4k]

I noticed today that the tempeture gauge will be all the way down on the C, and then it will intermittantly jump towards the middle and then back down to C. This happens when my car is having a rough idle at a stop. Is this almost a sure sign of the tempeture sensor?

Jay

 

[JayTye4k]

Any ideas?

Would the Temp Sensor or the Thermostat cause this?

 

[Jeff Leavitt]

Stumbles at Idle

Hi,

I just started having the same problem today. I do have a check engine light. Stopped at Auto Zone to get the code read. Was showing a 93 mostly and 93 didn't show on the AZ computer. I got the print out for the 95 & 96 codes but I don't think that is the problelem. Runs great except the idle goes rough after about a minute. Mines a 91 with the 4.0 motor...Help!!! Thanks for any idea's you may have.,.... Jeff

 

[aldive]

What was the exact code designation?

 

[Jeff Leavitt]

Al,
The code was a 93, but that code does not show up on the Auto Zone parts computer. My temp gage is o.k. but anyone think I should change the engine temp sensor? Noticed in a earlier post that cured the problem. Right? thanks......jeff

 

[aldive]

Al,
The code was a 93, but that code does not show up on the Auto Zone parts computer. My temp gage is o.k. but anyone think I should change the engine temp sensor? Noticed in a earlier post that cured the problem. Right? thanks......jeff

Codes are designated, for example, P0103; not two digit numbers.

 

[Jeff Leavitt]

Went to another AZ store and had the codes read again. This time AZ says Oxy Sensor. Also says I have two on my '91. I buy two and start looking to locate on the X. Chilton's says I have two as well. Long story short, I could find one, but not two. So I check this board for related posts. Sure enough, Mr Shorty here says 91 only has one. O.K.. I replaced the O.S. and vehile does run better, but still feel a lurch after idling in gear for about 30 seconds and the tach will drop to 5-600 and be running rough. Throttle response immediate, and runs fine otherwise. Any Idea's???