Hi All,
Time to say hello. Got my 2002 SLT+ 5.9LD 4 weeks ago and so far am fairly happy with it. It was time to retire my '91 Cherokee. I've had a run of problems, none of them beyond my capabilities as I consider myself a reasonably capable shade-tree mechanic.
I do have a problem that I am seeking some input on:
When I run the A/C and the temp goes up a little (to be expected when running A/C) the Overdrive disengages when I coast. The change down is rough. When not running the A/C this does not happen.
I've removed the check valve and installed an aftermarket trans cooler up in direct air-flow however this did not really help. Of course I've changed the fluid and filter and used ATF+4. IMHO it is heat that causes it, but I really don't know how to cool the trans down any more. Any thoughts?

Oh, one other question - where is the Air Intake Temp Sensor? I read that it is on the intake manifold - but where?

 

I may be able to help with the a/c problem. Do you have an auxilliary efan? It's located in between the rad and clutch fan. Sometimes they go out. I had your symptoms before and after I replaced the efan, my temp went down to normal even with the heat. You can see if the efan is working by running the a/c and using a flaslight aim it at the back side of the rad and see if there is an efan spinning. It should be spinning because the a/c is on. It should be off w/o the a/c. The relay for the efan is located in the PDC located in the engine bay in front of the brake booster. You can switch out any relay cause they're the same. See if that helps the efan to work. If it's not the relay, then you may have a bad efan. You can test that out by crawling under the front of the D and reach up to a green-colored connection, that would be the efan connection. Disconnect the connection and run a hot line directly from the battery to the connection, if the fan comes on, then you may have a bad fuse. If the fan remains off, you may have to replace the efan. There are many tutorials on how to replace the efan on this site. Good luck and keep us posted.

 

^what he said

 

Of course he does. Factory gear on 2000+

Now if it is working is another story.

IndyD

 

Thanks Guys.
Ok, yes I do have the e-fan and I am sure it is working but I will check it out today. On that subject, on my Jeep the e-fan is thermatically controlled and does not run all the time the air is on. Is the D the same or is it supposed to run all the time? I'm thinking that perhaps it is cutting out when hot.

Oh, I did find the Air Intake sensor.


Phil.

 

on these trucks the efan runs whenever the a/c is on, or when the temp gets above (i think)210

 

On my Durango, the efan is almost always on, even if the a/c is not on. Is it normal for the efan to constantly run when the engine is at operating temp and a/c is off?

 

I do believe the efan's been designed to be on to help in cooling the engine even with the a/c off.

 

yes the efan will go on if the engine gets hot enough, but most of the time it should be off if the a/c is off

but keep in mind that the defrosters turn the a/c on so if you have the defroster on the e-fan will be on

 

Update. Started her up this morning and turned the A/C on. E-Fan came on immediately which it is supposed to and confirmed its operation. Turned off A/C an E-Fan shut off as well. Again this would be normal as the engine was cold.
Drove home this afternoon in the heat and the tranny did its usual kick-down bs. Checked the E-Fan with the system hot when I got home and it was roaring along nicely.
I'm beginning to think that I'm running hotter than the idiot gauge tells me. Next step is cooling and trans temp gauges I think.