So about a year and a half ago I had a major overheat condition on a trip in my RV. It is based on a 1990 E-350 with a 460 CID engine. I suspect the overheat condition cooked my PIP sensor, which caused shutdowns when the engine bay ambient temperature got above a certain point, and I believe it also cooked my engine temperature sensor, as since then I was experiencing very rough idling when cold. The engine idled fine when warm. My mechanic had already replaced the Idle Air Control Valve as a guess and it had no effect. So, today I replaced the temperature sensor, and it solved the rough idle problem when cold.

Note that this is the temperature sensor that the engine computer uses, not the temperature sensor for the gauge on the instrument cluster.

I bought it from Advance Auto Parts. It is BWD brand:

https://shop.advanceautoparts.com/p/...058/20474729-P

It is normally about $30, but with the points I had and a 25% discount code I got it for about half that. I really like Advance Auto Parts. They have a great web site, free shipping to your home over $25, and free pickup at nearby stores. And, if you don't need it, you can return it to your local store. Also, the web site routinely hands out a 20% discount code all the time, and I have found that if you put things in your shopping cart and sit on them for 24 hours or so they will send you a "tickler" email with a 25% code.

You will need a 1" deep well socket to remove the sensor. A 1" open-end wrench might work - I didn't have one to try. I did try a crescent wrench and there was not enough room to engage the flats nor turn the wrench. The 1" socket made the job easy. It cost abut $8 from Oreilly's.

First, you will want to drain off some coolant. If you do not, when you remove the sensor you will drain it then - all over your engine and driveway.



Next, you will need to remove the air cleaner assembly.

The sensor is right next to and behind the distributor, on the driver's side, in the intake manifold In this photo I have already removed the connector from it. You will need a flat-bladed screwdriver to pry the connector off of the sensor. In this photo, the orange flashlight is shining on the sensor.



Here is a close-up:


Here is the new sensor with the 1" socket:


Here you can see the socket, with an extension, dropping down on to the sensor:


New sensor vs. old sensor:


The sensor hole with the sensor removed:


I put some blue RTV on the threads and screwed the new sensor in place:


Then I plugged the connector back in, and fired up the engine and checked for leaks.

The engine now idles smoothly when cold, so I assume this was the problem.

 

Very helpful! Thanks for the pics, and for posting!

-Kyle

 

Glad it helped!

Steve

 

I know this thread was a while back but hoping to get some clarification on the ECT location. There is a sensor right next to the distributor, which looks to be what you are replacing there but I just can't tell. Since there is an almost identical sensor slightly behind the distributor, under the idle control unit. Do you know which one is which? And what the other sensor might be. Here are the photos of them on my 460:

 

There are two temperature sensors in the intake manifold. One is for the EEC to monitor coolant temperature, and the other is for the instrument cluster gauge.

"The sensor is right next to and behind the distributor, on the driver's side, in the intake manifold In this photo I have already removed the connector from it. You will need a flat-bladed screwdriver to pry the connector off of the sensor. In this photo, the orange flashlight is shining on the sensor."

Steve

 

Hey Steve, thanks for the quick reply. My 1990 F250 has three sensors seemingly then: The EEC, the temp sending unit, and one I can't identify but that looks exactly like the EEC and lives under the idle control unit. I guess it doesn't so much matter if I know what that one does as long as I replace the correct one haha. Thanks for the clarification, and I'll replace the one right next to and behind the distributor.

 

I believe they have unique connectors so you can't screw it up.