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-   -   rev limiter? (http://www.wranglerforum.com/f218/rev-limiter-17471.html)

jeepjason 04-09-2008 12:30 AM

rev limiter?
 
I have a 94 4cyl 5spd. I just did a complete rebuild on the motor and have replaced the dist., tps, map sensor, o2 sensor, pcm, idle solenoid. I scrubbed the throttle body and have done every other r & r I could think of. The problem I'm having is that the motor will not rev over 4000 rpm. It makes no difference whether it is in neutral or any other gear, as soon as it hits 4000, it starts to cut out. Does this vehicle have an accessable rev limiter or is this something that can be programmed into the PCM? I'm at wits end here and could sure use some help. Thanks in advance!!

houseofpain11 04-10-2008 06:45 AM

serious? didnt know they would rev to 4000

[TheYJGuy] 04-10-2008 11:24 AM

Yea, I think its only the 4bangers that rev to 4k

jgwalt 04-10-2008 10:34 PM

are you being sarcastic? i was never aware of a rev limiter on my 4 banger. mine will rev all the way up til it blows up, never done it though. same jeep too. 94 2.5L. heh....

jeepjason 04-11-2008 12:35 AM

Thanks for the help! You guys are definitely more helpful and fun than an all night dentist. My wife thinks this whole process is funnier than hell. She says I spend more time with my jeep than I do with her. ( while true, I fail to see the point, ) If my jeep had boobs and a crotch, I wouldn't need her at all.

[TheYJGuy] 04-11-2008 02:28 AM

Quote:

Originally Posted by jeepjason (Post 217327)
Thanks for the help! You guys are definitely more helpful and fun than an all night dentist. My wife thinks this whole process is funnier than hell. She says I spend more time with my jeep than I do with her. ( while true, I fail to see the point, ) If my jeep had boobs and a crotch, I wouldn't need her at all.

:D

[TheYJGuy] 04-11-2008 02:28 AM

Quote:

Originally Posted by jgwalt (Post 217302)
are you being sarcastic? i was never aware of a rev limiter on my 4 banger. mine will rev all the way up til it blows up, never done it though. same jeep too. 94 2.5L. heh....

No sarcasm here. Sarcasm is immature and lame.

konacustomathlon64X2 08-02-2014 09:22 AM

same problem as O.P. in 95/2.5L
 
I know this is an old thread but....JeepJason did you ever find out what the hell is causing that 'rev limiting effect'? I have the same problem on a 95 Cherokee 2.5L that I rebuilt a few years ago. I never had this problem until maybe 2 months ago and I don't know exactly when it started. I had a bad tps and had an extra that seemed to test ok so I put it on there and seemed to fix the problem with the tps. I also changed the fuel filter because I had dropped the gas tank out. I put the gas tank back in a drove it on the old filter a short distance and then changed the filter. The engine has a new fuel pump from when I rebuilt the engine as well as some rebuilt injectors I got off of e-bay which are also on my 4.0L and it has no problems whatsoever with those same injectors (purchased from the same guy off of e-bay).

I took the computer off and sent it in to a shop (that specializes in just vehicle computers) to have it looked at recently because I was having some serious problems. It turned out to be a combination of things but not the computer. This '4000 RPM rev limit problem' is the last nagging thing with this Jeep and its driving me crazy. I have done all the things you mentioned in your post pretty much and can't find the problem.

konacustomathlon64X2 08-02-2014 09:24 AM

I know this is an old thread but....JeepJason did you ever find out what the hell is causing that 'rev limiting effect'? I have the same problem on a 95 Cherokee 2.5L that I rebuilt a few years ago. I never had this problem until maybe 2 months ago and I don't know exactly when it started. I had a bad tps and had an extra that seemed to test ok so I put it on there and seemed to fix the problem with the tps. I also changed the fuel filter because I had dropped the gas tank out. I put the gas tank back in and drove it on the old filter a short distance and then changed the filter. The engine has a new fuel pump from 3 years ago when I rebuilt the engine as well as some rebuilt injectors I got off of e-bay which are also on my 4.0L and it has no problems whatsoever with those same injectors (purchased from the same guy off of e-bay).
I took the computer off and sent it in to a shop (that specializes in just vehicle computers) to have it looked at recently because I was having some serious problems. It turned out to be a combination of things but not the computer. This '4000 RPM rev limit problem' is the last nagging thing with this Jeep and its driving me crazy. I have done all the things you mentioned in your post pretty much and can't find the problem. One last thing, I changed the CAT back exhaust as well 3 years ago when I put the engine back in. Somebody mentioned to me that it might be a plugged CAT so I took the exhaust completely loose from the manifold so that it was just an open manifold and still had the same problem. It would not go past 4K RPM even in the driveway with no exhaust.

MSNRC 08-02-2014 09:28 AM

My 05 TJ cuts out at 5

konacustomathlon64X2 08-08-2014 10:02 PM

I found what the problem was a few days ago!!! I am posting this because I know that there is somebody out there looking for an answer to this just like I was. Just to give a few essential details again I will mention that I have a 1995 XJ ( I know...its NOT a wrangler but w/e its the same drivetrain) with a 2.5L and an AX-15 manual trans (swapped from AX-5).
I have replaced almost all of the sensors in the last 3.5 years since I rebuilt the engine because either they failed or I thought they failed. I checked everything and I mean EVERYTHING I could think of and ended up just swapping a few parts between my two Jeeps (other is a 1995 with 4.0L and AX-15 trans) until I found it. It ended up being a brand new MAP sensor that I had put on there while trying to find a solution to what was at the time a much more complex set of symptoms because of multiple simultaneous problems. I bought a new MAP sensor once I found it was bad and it has run great!

Just so you know here are the symptoms I was getting: Would not rev past 4000 RPM no matter what I did and acted like it was bouncing off of the rev limiter right when it would hit 4000 RPM, some hesitation esp at low RPM and a noticeable loss in power all around (not a lot but def perceptible), occasional backfire up through the intake esp at low RPM when using a lot of pedal, running rich. It was not running rich to the point of smoking but if you went to the tail pipe it would make your eyes water/burn and your nose would burn too from the fumes of unburned fuel. I never got a check engine light/code on the 2.5L. I even did the key trick (on/off/on/off/on and wait for blinks). However I DID get a check engine on my 4.0L engine when I put the bad MAP sensor on it! In fact the 4.0L engine would not hardly run with the bad MAP sensor installed! That is strange to me because they're the same thing other than 2.5 vs 4.0L....meh whatever.

I really hope this helps somebody someday as I was looking everywhere and found several threads but NOBODY would freak'n come back and post what they found, so here you go, my golden nugget to you ;) .

Nubby55 08-10-2014 09:50 PM

Thank You so much for letting everybody Know.


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