My mechanic tested all of my sensors and told me the TPS was showing low. He said he adjusted it but I knew these are not adjustable. Plus all of my symptoms lead to the TPS. When I removed it and compared it to the new one I could see the spendle was not lined up the same. It was causing the throttle plate to have less resistance at open and close. Anyway, I racked my brain for two months before I figured it out. The mechanic said it seemed fine even though it tested low.

 

A TPS sensor can be tested by using a digital Voltmeter. There are 3 cables, connect the positive to the center and negative to the black ground cable by back probing the connector. Turn the ignition on without starting the car, and check ur readings. At closed it should read around .2 volts, and slowly push the throttle lever and observe how smooth the voltage goes up until around 4.8 volts at wide open. If the voltages are off or if the readings are too erratic while moving the throttle open then it needs to be replaced. it doesn't have to be exact to those readings what's more important is how smooth the voltage goes up to around 5. I found my aftermarket sensor read from .5 to 3.5 volts straight from the shop but it ran fine... Well for a short time at least and then it started acting up, I could tell the gas mileage went down and it smelled rich because it wasnt mixing fuel/air properly to the throttle. I put back the OEM TPS again and it's fine now.

 

will a bad map sensor cause misfires, and rough idle and all that? because i was playing around with all the sensors on my throttle body yesterday and when i unplug the tps is shuts off, which makes sense, the temp sensor increases the idle, and when i unplug the map sensor it changes very very little sometimes nothing changes at all

 

did you ever check for codes ? just becausea a prt is new dont mean it works right

 

do a compression test, you could have a blown headgasket and it not burn any coolant. if for some reason you have no compression in a cylinder it will misfire

 

It can but it only measures the preasure in the manifold. When they start going bad they often just cause a high idle.

 

i got the codes checked, there was a code that said something was wrong with the tps, so i got a new one, still doing the same thing, did a vacuum test, its perfect, did a compression test all cylinders are pretty much equal at about 125, oil is clean, im not loosing coolant, i even pulled the valve cover off to check for cracks in the head and to check all the lifters and everything, everything is fine, and now there are no codes at all, its definitely better with the new tps but its still not very driveable

 

is this the years with the heat soak problem with the injectors?

 

https://www.cherokeeforum.com/f2/200...s-1227/index2/

 

did you spray carb cleaner around to check for vacuum leaks it common for
the rear intake bolts to loosen up and cause small leaks

 

yeah i did that too, that was the first thing my stepdad told me to do, didnt have anything happen when i did

 

id try new plugs even thought they looked good which ones you using if its the e3 theres been problems with 4.0 not working well with them,

 

if it's throwing a code for the TPS then your new TPS could be bad. Did you buy it from the dealer or somewhere else?

 

bet its an 02 sensor, mine did the same thing, and never threw a code. had pending codes for rich and lean depending on engine temp and guessed, I was right

 

its got brand new champion platinum plugs as of friday, thats the first thing i did

it was throwing the code before i replaced it now its not showing any codes at all after the new one

i dont have any pending codes at all, i wish i did lol, then i could figure it out, i had the code for the tps and now with the new one in ive got nothing