CALLING ALL MECHANICS!

[stevetimleck]

here is the situation: I bring in my 98 sport 4.0 sohc to complain about bad idle after start up on cold mornings.
$200.00 for manifold gaskets, no change then he says IAC no parts in stock. Later I buy my own from ford (i moved far from first dealer) I install IAC but dont reset computer. No change but idle is now higher about 12/1300. I plan to take it in to check out cam tensioners soon but.
Now the real problem today it starts to run very hot and the 3 and 4 shift is jerky and done at low revs then doesnt kick down easily (as if lock up is sticking) in neutral moter revs fine but idle is high and temp is very high. I already tried unhooking battery but no change.
Please help anyone!

 

[stevetimleck]

update

I just put back on the old IAC, this time with batt cables off and no difference.
I think the tranny stuff is being caused by the extra rpms the car is putting out

 

[01EB5.0]

Did you maybe knock looase a vaccum line? are you sure the IAC was plugged in all the way? an idle at 1,200 usually means inoperative IAC. Is your fan operating behind the radiaotr? Are you running your A/C during this? How many miles? are any lights on (check engine or tranny light) let me know and I'll try to help.

 

[stevetimleck]

I did my best to see loose hoses there were none that I can see no to all other questions iac was on tight. one thing though is when engine is warm and i start it the idle is low 750/800 then after 30 seconds it slowly climbs along with temp
thanks 108,000kms approx 65,000 miles

 

[stevetimleck]

the thing that is most confusing is the overheating!

 

[yob_yeknom]

The reason it revs higher as the temp goes up is it is trying to cool itself off. It revs up to turn the water pump faster to help it cool.
Sounds like you have an overheating problem that's causing the unusual idle. Check your coolant level to start with.
As for the weird shifting, have you checked the tranny fluid? Was the engine running really hot when the bad shifting occured?

 

[stevetimleck]

yes the engine was hot when rough shifting occured.
Its booked to go to dealer wednesday. Where should I begin to look for overheating problem after coolant?
how do i check thermostat?

 

[BajaXplorer]

Did you replace the "figure 8" gasket under the IAC. They flatten out and leak especially on the SOHC motor.

Hope it works out. Bad idle is a most annoying symptom thats difficult to track.

 

[stevetimleck]

is it the green o ring type

 

[stevetimleck]

Just saw this after a thermostat search what do you guys think?
If it happens when you are stepping on the gas to take off from a light, then it is probably your thermostat. My '97 SOHC thermostat went out last March. The probelms started a week earlier with a higher than usual idle. After a week I noticed my temperature gauge went up to H every time I took off. When I got in open traffic and was light on the gas, my gauge would drop down to a little above the middle of the range which was still higher than normal for mine.

 

[hijinks]

I had a problem with a bad thermostat once that would bounce all over the place every so often but read a lot higher then it should have. Once it was replaced everything seemed to settle down with engine revs and such

 

[01EB5.0]

yeah, ford is known for crappy thermostats in the explorer. I put in a stant 195 degree T-stat about 2 years ago and it's been fine...now my gauge is fluctuating more though...who knows..it's not getting too hot though.

 

[kps36]

Like Travis, I had a very low reading on my gauge about 2 yrs ago. I got the Stant 195, but also when in there changed out the temp sensor to the computer (right above the Stat). I did not change out the gauge sensor. But didn't need to. Now when warm sits dead center and I am assured that the PCM is geeting the proper info. If I remember correctly the sensor was about 25-30$.

 

[Robert]

stevetimleck -- I was the one that posted the other message about the thermostat. That definately sounds like the problem. Yours is probably sticking closed. Whenever your computer sees your temperature run higher than normal, it bumps the idle up to try and cool things off. The thermostat is easy to replace and easy to get to. I would do that before taking it to Ford. If they do it, count on about $150. Higher if they convince you that you need a complete cooling system flush for $80 more. You can buy a thermostat for less than $10 and spend the 1/2 to 1 hour putting it in. Pick up a Chiltons or Hanes manual for your Explorer and it will have pretty clear directions.

 

[01EB5.0]

I would recommend picking up a chiltons over a haynes because from my experiance chiltons is more through

 

[stevetimleck]

thanks all

you guys were totally right i changed the tstat and presto chango perfect
tomorow i will learn if rough cold start is still there
thanks again