Topic: What all comes off the 2.5 L throttle body; swapping to the 4.0L throttle body

[countryboy15]

IT bearly catches a spark with the pedal to the floor, but won't keep going. It would not start with me pushing the pedal to the floor. I am going to try and start it again today, if it dont I am going to check everything you said to. I couldn't get the TPS off during the swap so I left it on, even when I PUT WD-40 on it(I didn't come back to this website until I had reinstalled the 4.0 L throttle body .

Take the not starting part back, IT started this morning but not last night, so my 2 cents is something is going out. I know it definitely isn't the starter changed that last week. ANY Ideas?

Also THe clunking type of vibration was still there this morning. THis morning when I got it started the idle speed is at 1000 rpm in neutral, I pressed the clutch and the idle speed went to about 1500 rpms, would the 4.0 L throttle position sensor do this?
Also what size torx bit fits the small torx bolts on the throttle body? The reason I ask I broke 3 different sized torx bits, a T-15H, T-20, and a T-20H.

I did swap the IAC, so if this is it, what to do?
ALSO I cant get the 4.0L TPS or the 2.5L TPS off, but I have yet to try applying heat to the torx bolts yet. Could the 4.0 TPS be the problem?

[oldjeep]

ALSO I cant get the 4.0L TPS or the 2.5L TPS off, but I have yet to try applying heat to the torx bolts yet. Could the 4.0 TPS be the problem?

It could be the problem if it is bad.  The 2.5L and 4.0L use the same TPS.

[countryboy15]

I am going to have to change it when I get the time to.

[TahoeYJ]

Just throwing this out there but when I swapped on my 4.0 TB, I had never previously read anything about swapping over sensors  Either that or I did and flat out forgot. I've never had a problem though with the 4.0 sensors on my motor... I did get mine off a like 96 or 97 Cherokee. Idle has always been the same and I've never had any weird issues....

[countryboy15]

Take the not starting part back, IT started this morning but not last night, so my 2 cents is something is going out. I know it definitely isn't the starter changed that last week. ANY Ideas?

Also THe clunking type of vibration was still there this morning. THis morning when I got it started the idle speed was at 1500 rpms immediately than gradually went down to 1000 rpm in neutral, would the 4.0 L throttle position sensor do this?
Also what size torx bit fits the small torx bolts on the throttle body? The reason I ask I broke 3 different sized torx bits, a T-15H, T-20, and a T-20H.

I did swap the IAC, so if this is it, what to do?
ALSO I cant get the 4.0L TPS or the 2.5L TPS off, but I have yet to try applying heat to the torx bolts yet. Could the 4.0 TPS be the problem?

[sharpxmen]

YJ 4.0L tps P/N: 5234904
YJ 2.5L tps P/N: 2264 270

they are different
 i used the 2.5L one when i did mine and had no issues

I didn't measure them though, i'll do that later tonight and will post back (i think it's a resistive pot - just a gut feeling).

[countryboy15]

seems to run good but there is a clunking type vibration when idling, any ideas on how to get rid of this?

[sharpxmen]

seems to run good but there is a clunking type vibration when idling, any ideas on how to get rid of this?

i don't think the clunking has anything to do with your throttle body swap

[countryboy15]

i don't think the clunking has anything to do with your throttle body swap

i dont think it does either but I didnt want to start a new thread if the clunking vibration isnt nothing. i just never noticed it before the swap.

[sharpxmen]

i dont think it does either but I didnt want to start a new thread if the clunking vibration isnt nothing. i just never noticed it before the swap.

i understand, i just don't know of anything that can be related so it would start right after a t/b swap - or at least i can't think of anything. where is it coming from?

EDIT: is your idle lower?

[countryboy15]

It feels like it is coming from the motor.

The idle goes up to 1500 rpms right off the start then will graually work back down to a little under 1000 rpms.

Thanks for all the help.

[sharpxmen]

It feels like it is coming from the motor.

The idle goes up to 1500 rpms right off the start then will graually work back down to a little under 1000 rpms.

Thanks for all the help.

you'll have to pinpoint it better, but just as a general guess since this is common in our Jeeps i'd say it's a hydraulic lifter or (less likely) a loose or broken bolt on your exhaust header.

1000 rpm is high for idle unless you have an auto (even then i think it's more like 900 but the guys with an auto should confirm that as i'm not really sure). I'm going to measure that tps and see if they're really different, not just the part numbers.

[oldjeep]

Might want to check if it's just an air leak.  Take a propane torch (unlit) and spray propane around the base of the TB.  If that increases the idle, then you have a leak.

[countryboy15]

I

you'll have to pinpoint it better, but just as a general guess since this is common in our Jeeps i'd say it's a hydraulic lifter or (less likely) a loose or broken bolt on your exhaust header.

1000 rpm is high for idle unless you have an auto (even then i think it's more like 900 but the guys with an auto should confirm that as i'm not really sure). I'm going to measure that tps and see if they're really different, not just the part numbers.

It gets to about 700-800 rpms idling, but it takes a while.

[sharpxmen]

I
It gets to about 700-800 rpms idling, but it takes a while.

the tps seems to be an active device not just a pot so i can't measure it - i need to use a 5v power supply but my lab p/s is out for repairs so i need to wait until it comes back. You need a T20 to take the tps off, i had no trouble taking them out, you need a good torx though - if you put the torx in and tap slightly on the end of it should help losen the bolts. You can also cut a slit across the bolt with a dremel cutting wheel and make it wide enough for a large flat screwdriver, that would most likely do it - aas far as hear, not sure, i'd be worried not to damage the tps. On a guess since the part numbers are different i would guess the output is also different so better use the one off your 2.5L - should go down to 750 to 800 rpm fairly quick, my guess is the tps that makes the difference.