Topic: throttle body upgrade?

[rockalot1982]

   is the throttle body on a 4.0 interchangeable on a 2.5? Is there any performance plus? THanks

[jcoleman]

yes. http://www.creeperjeepers.org/throttle%20body%20swap.html)

The post Just a few down about weekend upgrades to the YJ has a little about throttle bodies too.  That's where i got the above link.

[Jeffy]

  is the throttle body on a 4.0 interchangeable on a 2.5? Is there any performance plus? THanks

A search here would have brought you this: http://4bangerjp.com/forums/index.php?topic=8.0

[aka-justin]

I just completed adapting a 4.0L Throttle Body from a TJ to my 2.5L YJ.  Only thing I had to do extra was capping off the extra MAP sensor port.  I have a lot more power at low RPM and while slightly depressing on the accelerator, but I'm noticing a small problem...

I noticed that it will stutter now when I punch it (More than prior).  I also have to slowly press down on the accelerator to bring up the RPMs up otherwise my power band turns into a power limp.  It has a fresh fuel filter, air filter, plugs, oil change, all the hoses are connected....

Any suggestions?  I'm going to try checking the and adjusting the TPS sensor this weekend. http://www.autozone.com/az/cds/en_us/0900823d/80/1f/e7/80/0900823d801fe780/repairInfoPages.htm

Thanks,
Justin 

[Jeffy]

Reset your PCM.

[aka-justin]

I'll give that a shot.

From what I read, I need to: disconnect the battery, let it sit for 15 min, then test drive it.

Thanks,
Justin

[Jeffy]

It may take a week or so for it to relearn what it need depending on how much you drive it.  Supposedly, if you ground the positive cable, it will drain any residual power in the capacitors faster.

[wi1dweasal]

quick question, can you take a throttle body from a 98 cherokee 4.0 and use it?

[Jeffy]

quick question, can you take a throttle body from a 98 cherokee 4.0 and use it?

Yes, it will work for your TJ.

[aka-justin]

It may take a week or so for it to relearn what it need depending on how much you drive it.  Supposedly, if you ground the positive cable, it will drain any residual power in the capacitors faster.

On the nose Jeffy; Thanks!.  Drove it about 100 miles last night and it now drives better.  No more bogging or stuttering.  It has more power with the throttle body than before, but it's no miracle; no more than 10 HP difference that I can feel.  I did notice it stopped slowing down so bad at slower speeds on hills and rough trails.
Diffently worth the $20 investment.   

Thanks,
Justin

[89fourbanger]

dumb question but if i do the 4.0 throttle body swap and want to do a throttle body spacer do i use a 2.5 and bore it out or a 4.0?

[jfrabat]

dumb question but if i do the 4.0 throttle body swap and want to do a throttle body spacer do i use a 2.5 and bore it out or a 4.0?

4.0L TBS for 4.0L TB; if you bore out the 4.0L TB, then it is better to get a 62mm spacer also...

[Bounty Hunter]

http://4bangerjp.com/forums/index.php/topic,4044.0.html

[Jeffy]

On the nose Jeffy; Thanks!.  Drove it about 100 miles last night and it now drives better.  No more bogging or stuttering.  It has more power with the throttle body than before, but it's no miracle; no more than 10 HP difference that I can feel.  I did notice it stopped slowing down so bad at slower speeds on hills and rough trails.
Diffently worth the $20 investment.  

Thanks,
Justin

I think what really makes it worth it is just the throttle response.

dumb question but if i do the 4.0 throttle body swap and want to do a throttle body spacer do i use a 2.5 and bore it out or a 4.0?

There is no 2.5L TBS that I know of.  Either 2.5L or 4.0L should go with teh 4.0L TBS

[cletz97]

do you have to change sensors with a throttle body for a tj?