What's the best way to get at the ECU temp sensor by the engine mount? If you jack up the frame does that improve things? I can't even really see it with the XJ just parked.

 

Jacking up by the frame gives you more room to slide under there, but otherwise long skinny arms help. I'm not sure if pulling the airbox out would let you get at it from above.

 

Note from DJ

Why do you want to look at the ECU temp sensor?

What year is your Cherokee?

 

Is it proven bad?

 

Check the sensor first as Cruiser suggests,

When I thought about replacing mine ('88) I figured I'd remove the motor mount to get better access. Thankfully I checked it and it was OK. As far as I know, it's still the original.

 

No, and I will check before replacing. Are there just two pins in the plug or are there specific pins to measure against.

I've been reading up on causes for poor fuel economy as I'm getting about 10 mpg, and the exhaust always smells rich. T-stat is new and the upper rad hose gets hot and coolant will boil if the rad cap isn't on. Dash gauge never gets above 60-70C, but I realize that has nothing to do with the ECU.

 

Yep, just two pins. Polarity doesn't matter. Make sure your disconnect it when you measure resistance. Check cold first, reconnect it, drive around to get the engine hot, then carefully disconnect (it's hot!) and test again.

 

Note from DJ

What is the YEAR OF YOUR JEEP? And is it a CHEROKEE or a GRAND CHEROKEE?

Always remember that we are not looking over your shoulder, so sometimes the details like my questions above will help you solve your problem. Thanks for the information that that you provided in your post 6.

For the onlookers 60C=140F and 70C=158F

 

MAP sensor is much more likely, as is the hose/tubing going to it.
Have you ever completed Tips 1 through 5 at www.cruiser54.com?

 

'87 Cherokee XJ

 

You really need to complete Tips 1 through 5 at www.cruiser54.com first.

 

Did you change the name of the website, Cruiser (see link in your post)? 😉

 

No. Fat fingers!!

 

Lol you changed it already I see
I liked the " cryuser" haha

 

As in boohoo...LOL.