Proactively replacing Sensors?

mde8965

TJ Enthusiast
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2004 - 50k miles, 4.0

So I am getting an intermittent CEL for TPS circuit low voltage. Confirmed myself as voltage is on the low side of normal even when not throwing a CEL. Figure the TPS is on its way out of here.

I have the TPS on order and heave a new Fel Pro throttle body gasket. Just wondering, if it were you, while messing around in that area, would you proactively change the IAC, MAP sensor or any other sensors (with Mopar of course)? Other than the intermittent CEL, the only symptoms it has are a fairly low (500 rpm) idle after warm up. I have already used cleaner in the throttle body/IAC
 
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I would replace the TPS only, see if that fixes the ce light.
If not, see if any other codes show and go from there.
If the TPS does fix the problem then you have just learned something about your TJ.

If you replace the other sensors with OEM sensors "while you are in there" you may well fix the problem, but now you don't know which sensor solved the cel issue.

It's not s bad idea, if you like, to purchase map or other OEM sensors now, just to have them for future use.
 
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I would replace the TPS only, see if that fixes the ce light.
If not, see if any other codes show and go from there.
If the TPS does fix the problem then you have just learned something about your TJ.

If you replace the other sensors with OEM sensors "while you are in there" you may well fix the problem, but now you don't know which sensor solved the cel issue.

It's not s bad idea, if you like, to purchase map or other OEM sensors now, just to have them for future use.
I agree with you. If replacing the other 2 sensors also involved removing the throttle body I would likely just do them all at once. But I’ll just do the TPS. Assuming the CEL will be gone. If the warm idle is still an issue I will reevaluate.
 
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I agree with you. If replacing the other 2 sensors also involved removing the throttle body I would likely just do them all at once. But I’ll just do the TPS. Assuming the CEL will be gone. If the warm idle is still an issue I will reevaluate.

I tried replacing sensors on an ‘87 Mustang that I had years ago proactively and it didn’t turn out too well for me. As KC mentioned, if you replace several things and it either solves or causes another issue it’s hard to tell what solved your existing issue or troubleshoot if a new issue pops up. For me and the Mustang it wound up being a brand new sensor that was bad, but it was hard to locate without putting all the old sensors back in and swapping one by one.
 
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I tried replacing sensors on an ‘87 Mustang that I had years ago proactively and it didn’t turn out too well for me. As KC mentioned, if you replace several things and it either solves or causes another issue it’s hard to tell what solved your existing issue or troubleshoot if a new issue pops up. For me and the Mustang it wound up being a brand new sensor that was bad, but it was hard to locate without putting all the old sensors back in and swapping one by one.
Agreed...one thing at a time.

Hope the 87 Mustang was a 5.0... Those seemed to have issues with the MAF sensors. I had an 88 convertible 5.0. Loved that car... Also had a 93GT and a 94GT that I bought new that was turned into an 11 second drag car... As soon as I win the lotto I will buy another fox body...
 
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Agreed...one thing at a time.

Hope the 87 Mustang was a 5.0... Those seemed to have issues with the MAF sensors. I had an 88 convertible 5.0. Loved that car... Also had a 93GT and a 94GT that I bought new that was turned into an 11 second drag car... As soon as I win the lotto I will buy another fox body...

Yes it was the 5.0 convertible. Had a lot of fun with it, but couldn’t escape the gremlins. I had a lot of issues with sensors, convertible top hydro pumps, transmission, wheel balance, etc.
 
I tried replacing sensors on an ‘87 Mustang that I had years ago proactively and it didn’t turn out too well for me. As KC mentioned, if you replace several things and it either solves or causes another issue it’s hard to tell what solved your existing issue or troubleshoot if a new issue pops up. For me and the Mustang it wound up being a brand new sensor that was bad, but it was hard to locate without putting all the old sensors back in and swapping one by one.
A bad new sensor, now that will make you insane, another reason to troubleshoot engine problems one step at a time like mde8965 said above.