Hey, I've been having this weird Idle issue for a couple of days, when i'm in gear and driving, and i press the clutch pedal all the way down, the rpm's should go down to idle speed. Instead, they hang around 1500 rpms or so for about 3 seconds, then drop down to normal speed. I have cleaned out my throttle body with seafoam, but haven't cleaned the IACV yet. This problem is getting more and more annoying, and at high rpms, it makes it feel like my clutch is slipping. I know it's not, it's an almost brand new clutch. Could the problem be the IACV?

I'm also using an auto ECU, could it be a product of that?

I know someone had this problem before, but I couldn't find the thread after searching on google.

Thanks in advance.

-Freddy

 

They're supposed to hang up ~ 1500RPM for a few seconds, this provides better RPM matching while shifting through the gears (I believe,) a little less wear on the clutch.

If you're shifting at 3k, and the next gear starts up at about ~2k or so, 1500 is much closer to match then idle...

 

My car has always done this since I had it at 40k, now at 85k, and I remember talking about this a long time ago and had many people say that it is supposed to be like that.

 

This normal... Even a factory manual does this... Dont worry about it.

 

hmm...it didn't do that for the first 500 miles..yesterday it just shot up to about 2200 rpms, and stayed there, until about 5 seconds later. I know that's definitely not normal. And since i'm still using Auto ECU, why would it do this?

 

Well you didnt say that... in our factory 5MT's when you put in the clutch it hangs right at 1400 (every time) for 2-3 seconds.

2200 all on its own, I have no idea...

 

well, could be a vacuum leak when I didn't tighten down the airbox assembly. I tightened everything down, cleaned the TB...and hoped for the best. It hasnt happened again today, but I'm just concerned about the rpm's hanging...if it's normal, i'll deal with it I guess. I'll try putting in the 5spd ECU, and seeing what happens.

 

I know that I've left my foot on the gas pedal sometimes while I'm shifting and that has caused it to hang higher in the rpms. 'course I've got some pretty big feet too. maybe that's part of the reason. Some of the pedals are pretty sensetive to even the faintest touch or pressure.

 

You probably just didnt notice it. I noticed it with in a few miles once I swapped.

I am still using a the auto ecu as well. Its the transmission itself that causes this. It is not computer related. Putting in the manual ecu will change nothing.

This actually a feature to help with driving the manual like tomservo said... It is your friend.

 

Especially the gas pedal!!

 

if I have the clutch disengaged, how would it be a product of the transmission?

 

What does it mean if my car DOESN'T do that??? The 1400 rpm "hang"? I've always seen an idle problem, where the engine speed will drop below idle when putting the car in nuetral and coasting. Instead, could this be tranny related somehow? There have been about 5 transmissions in my car since I've had the car (PLEASE NOTE: the reason there have been so many in and out was because all of the replacements for the original were faulty somehow, and continued to leak fluid.), so maybe something isn't connected right? I haven't performed a vacuum test, but was going to get around to it soon, nor a compression test (wasn't even planning on that one actually). Does any of this make sense?

 

I would GLADLY have the engine speed hang around 1400 rpms for a few seconds rather than have my car's engine speed fall to the point of shuttering/almost stalling.

 

Youre right... Then it must be flywheel related... something mechanical, not ecu related though.

 

which leads me to think it might be a vacuum leak or diry IACV. If the problem persists, i'll clean out the IACV and see what happens.

 

Im tellin you man, it completely normal... Dont worry about it (unless youre talking about the 2400 thing). My friends 96 which is a factory manual does it too. All ways has. My car used to never ever do it until I did the swap... I was expecting it.

 

bump for post 12, anyone want to shed some light on the fact my car doesn't do this seemingly ''normal'' performance?