When I sit in neutral and rev the engine, the rpms take a second to go back down. All i do is press the gas once and take my foot off and the rpms don't fall back down instantly, is this normal?
RPMs not falling quickly when revving engine: Is this normal?
- Thread starter Chasitek
- Start date
I dont know about the rpms, but the wires hanging aint normal
lubricate the throttle linkage, look for corrosion, an clean out your throttle body.
lubricate the throttle linkage, look for corrosion, an clean out your throttle body.yeah the wires are from me, I've been too lazy to mount my mechanical oil gauge. It doesn't do this all the time, i'll get another video of the dash this time. Do you think it has anything to do with my transmission or clutch? I replaced the throttle body like 2-3 months ago with one from a 4.0 and bored it out. It also has a throttle body spacer.I dont know about the rpms, but the wires hanging aint normal
Take the throttle body spacer off, those don't do anything on a modern fuel injection engine.
Was it doing this before you replaced the throttle body? I would try cleaning your IAC first off.
Was it doing this before you replaced the throttle body? I would try cleaning your IAC first off.
Clean the IAC, put the stock throttle body back on, and like @Chris said, take the spacer out.
Read this: https://wranglertjforum.com/threads/how-can-i-get-more-performance-out-of-my-2-5.4062/
https://www.carsdirect.com/aftermarket-parts/performance-accessories-throttle-body-spacers - if you added more air, maybe its takin more time to wind down, were their any springs on the linkage that you strecthed, changed, when you added the spacer. is it the right bore an spacer for the motor. were there any other adjustments needed when you added the spacer? did it do it before you added the spacer, an trans work? if its doing it not in gear, I am not sure how it would have anything to do with the transmission, unless, they adjusted it when they did the work on the transmission, or bent the linkage. is the clutch bracket the same as the gas pedal bracket? that could have gotten bent? I had a steering line on a jet ski i had to replace cause its just old, an hanging up, an corroded, inside teh sheath. get a video of the linkage under the hood working, an underneath the dash of the pedal working. lubricate the movement points of the gas pedal underneath, without getting it on the gasbrake or clutch pedal. is there any air getting past the gaps in the throttle body spacer when say the jeep is on a different grade of ground. do you put anything in the gas, on a normal basis or at different times. do you same octane gas at every fill up?
look around on the internet, people are having problems putting spacers on, an then having shifting problems with their manual transmissions. some say they were able to adjust them some how. tell the shop you got a spacer on there, that they may not have seen, or even know it could be a problem an see if they can adjust it accordingly, or like them guys said, take the spacer off, an put back to normal, to see if that fixes it, an the shifting problems.
https://www.answers.com/Q/What_does...t_work_in_regard_to_an_automatic_transmission is there a kickdown cable on the jeep, that is running different now with the throttle body expansion? did you start having problems with the transmission before you installed it? maybe not even needing the transmission work to be done? man, i hope people aint putting spacers on, an then going an getting their transmissions rebuilt, not knowing their could be an issue with it. would a transmission shop, take some people for a ride on this situation? just got to wonder, an do transmission shops even know this can be a problem an dont even know a spacer was put on, an then, cant figure out the problems, an then geting into lawsuits with their customers.....we keep stumbling over all kinds of stuff in this tj wrangler forum.....
hey, chris, is there a way for those posting questions for help, to ask them, if they did any previous modifications, to the jeep, that may affect the issue at hand. or like a note that says, please give all modifications done, concerning the system in question, that you may or may not think is relevant, when you post a question for help.
hey, chris, is there a way for those posting questions for help, to ask them, if they did any previous modifications, to the jeep, that may affect the issue at hand. or like a note that says, please give all modifications done, concerning the system in question, that you may or may not think is relevant, when you post a question for help.
As recommended (by most, anyway) above, get rid of the throttle body spacer which is doing NOTHING for your TJ's type of throttle body. Nope, they don't cause more air to flow. Spacers only help when placed under older "wet" air intakes... with wet meaning it is delivering fuel as well as air. Carburetors and first generation throttle body injection (TBI) systems did that. Modern throttle bodies like our TJs and newer Jeeps use pass air only. The fuel is injected well below the throttle body on modern engines.
My guess on your rpms coming down so slowly is your IAC (idle air control) is dirty enough so it isn't responding fast enough to signals from the computer. You can clean it with an aerosol can of throttle body cleaner with it still in place. It's done like you'd clean the throttle body with one big difference... you must keep the engine at idle rpms while spraying the cleaner into the throttle body. Only at idle rpms will the IAC be drawing air in through itself which is what will suck the cleaner in through it. The cleaner will flood the IAC and cause the engine to stall but that is good as it lets the cleaner sit in there a little longer while you restart the engine. Do that enough to have used a third of the can of cleaner and the IAC should be clean. See if that doesn't help your slow return to idle issue.
My guess on your rpms coming down so slowly is your IAC (idle air control) is dirty enough so it isn't responding fast enough to signals from the computer. You can clean it with an aerosol can of throttle body cleaner with it still in place. It's done like you'd clean the throttle body with one big difference... you must keep the engine at idle rpms while spraying the cleaner into the throttle body. Only at idle rpms will the IAC be drawing air in through itself which is what will suck the cleaner in through it. The cleaner will flood the IAC and cause the engine to stall but that is good as it lets the cleaner sit in there a little longer while you restart the engine. Do that enough to have used a third of the can of cleaner and the IAC should be clean. See if that doesn't help your slow return to idle issue.
xackley
TJ Enthusiast
My 2.5 idles down to 1K, sets there then a second or 2 later down to 750-800
Do you have that extra spring on the throttle linkage, and if so, is it tight at idle.
I would be testing that under the hood pulling on the linkage. Then have someone else push the peddle to observe if the linkage returned quickly
Do you have that extra spring on the throttle linkage, and if so, is it tight at idle.
I would be testing that under the hood pulling on the linkage. Then have someone else push the peddle to observe if the linkage returned quickly
Seeing that video and the wires hanging down etc makes me wonder if you've been blaming the transmission shop for lots of things that have nothing to do with your transmission
the throttle body has been on there for a at least 7 months, I just like the sensitivity of the throttle.
The throttle body spacer and 4.0 throttle and stuff has all been on there for a while, this rpm hang is recent. However I just got a cold air intake like 3 weeks ago, could that be doing it?https://www.carsdirect.com/aftermarket-parts/performance-accessories-throttle-body-spacers - if you added more air, maybe its takin more time to wind down, were their any springs on the linkage that you strecthed, changed, when you added the spacer. is it the right bore an spacer for the motor. were there any other adjustments needed when you added the spacer? did it do it before you added the spacer, an trans work? if its doing it not in gear, I am not sure how it would have anything to do with the transmission, unless, they adjusted it when they did the work on the transmission, or bent the linkage. is the clutch bracket the same as the gas pedal bracket? that could have gotten bent? I had a steering line on a jet ski i had to replace cause its just old, an hanging up, an corroded, inside teh sheath. get a video of the linkage under the hood working, an underneath the dash of the pedal working. lubricate the movement points of the gas pedal underneath, without getting it on the gasbrake or clutch pedal. is there any air getting past the gaps in the throttle body spacer when say the jeep is on a different grade of ground. do you put anything in the gas, on a normal basis or at different times. do you same octane gas at every fill up?
Nope, just trying to make sure anything that exists doesn't have to do with the transmission seeing as I paid 2119 dollars for someone to fix it and got it back fucked up with an idiot trying to convince me that when my car wouldn't go into 5th gear was because it had to be worn in. I'm not going to let anything slide for them as I am going there with a list of things they need to check or i'm going to sue them. The wires go to a mechanical oil pressure gauge which has nothing to do with the transmission. Just because you see wires doesn't mean squat. If you really think there's nothing wrong with my transmission because there are bare wires, then i will bet you 500 dollars to come drive my jeep and tell me the transmission feels perfect. The transmission shop takes the jeep back and works on it every time because they know something is wrong with it.
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It's been a super long time (weeks) and several pages of posts and you still haven't taken your vehicle to a different shop to have it "fixed".
Hate to be a skeptic but just sayin'....
Why not put that $500 towards a diagnosis .
I would clean the IAC as I suggested above. I would also look for any potential vacuum leaks. It may be normal though so I wouldn’t spend much time on it.
It also could potentially be related to the work the transmission shop did, so before anything else I would try and get that sorted out.
It also could potentially be related to the work the transmission shop did, so before anything else I would try and get that sorted out.
http://www.smokeoutrally.com/ take the jeep over here in june, if it aint fixed by then, sure some people there can see if its shifting right
I don't just have 500 dollars laying around. I have a full time job and school. On top of that I parked my friends car and it got towed, my plate is due for a renewal, I have 2 dogs that need a vet appointment, and I lost my wallet with 100 bucks in it. I don't have time to bring my car to other shops to have it looked at. Also I just moved to where I live right now and don't know any shops around here. The transmission rebuild has a year warranty and it is drivable so until I get on summer break I really don't have time to bring it in anywhere. Sorry if I was upset but this transmission is genuinely fucked up and I couldn't even afford the rebuild to begin with. I just don't have time or money to keep investing in this issue when I paid so much to have it fixed
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