Weird K24 low idle [Archive]

iDom

07-24-2012, 12:15 AM

I did a k24 swap a few months ago & when I last drove the car tonight, I realized my car was idling really low at stop lights & whatnot. I'll go further in to details..

Ok so I have pretty stiff motor mounts in my car & at stock idle my car would shake really really bad so I went in to KPRO & raised my idle to 900

Here's my set up
-k24a2 block
-k20a2 head
-RBC
-SRI
-KPRO
(I have no vacuum leaks, I checked)

Earlier today I did a datalog run because another fellow EPHatcher is doing some e tuning for me. It ran perfect fine & when I pulled in to my driveway & sat there for a minute while I was saving the .kdl, right before I closed kmanager I noticed the ECT shot up to about 195 degrees. Normal temps while I'm driving is 179-181. Obviously I just got done with a WOT pull so it should be hot but I don't know if it has anything to do with my situation. At the time it was about 90 degrees here with 60% humidity so the higher temps, especially at idle make sense. So I turned my car off & later during the day I took off & noticed the low idle. Some more background information..

-It never stalls out on its own
-It has a CC lightweight flywheel
-Even with the AC on it doesn't stall at idle
-Idles at about 400-450 but set to idle at 900
-Just started doing this

Idk why it's doing this or if there's something wrong or what? Any ideas? I may just be worrying about nothing but, it doesn't normally do this.

As always, thanks in advance.*

Ba82Ep3

07-24-2012, 01:01 AM

Did your TB sit without use for a while? The IAC valve might need to come off and be cleaned. Theres a good chance its has carbon on the rotor and moisture in the air made it worse.

Have you tried moving the IAC slider in KManager... and see if it solves the issue? You can do that while idling... upload... check... upload... check etc. If the idle still drops, odds are the IAC need cleaning.

iDom

07-24-2012, 04:49 AM

I will try that first thing this weekend. My TB sat for 2 days while I swapped the new motor in but it does have close to 180k miles on it so I would doubt that it possibly needs cleaned.

Thank you sir.

iDom

07-24-2012, 05:18 AM

Also, I just noticed while driving to work. If I let my car idle for a little bit (about 20-30 seconds) the idle will normalize and idle at what it is supposed to. Does that give anymore insight on the problem?

Ba82Ep3

07-24-2012, 08:08 AM

Double check to be sure you dont have any vacuum leaks. You may have one between the IM and the head, or the TB and the IM... and its so minute it only presents itself at certain head temps (as it expands or contracts). It is a metal gasket after all... and prone to this type of leakage. Its one reason i clean up EX and IM head surfaces by hand to be sure the machine markings are smoothed out.

Double check all hoses... use the starter fluid trick to check for idle change.

iDom

07-24-2012, 08:36 AM

Okay I can give that a try sometime too. My EP3 SRI doesn't fit that well on the RBC/karcepts/EP3 TB too well, I wonder if that not having a good clamp could cause it too.

I read something somewhere about "re-learning" the idle or something like that on k20a.org while searching. Something as simple as just reloading the .kal?

Ba82Ep3

07-24-2012, 08:44 AM

iDom

07-27-2012, 01:19 PM

Meh. Idle relearn has been debated... and even a few techs have said it does AND doesnt exist. I cant tell the difference in KPro (comparing sensor bar data)... so i lean more towards no... or the difference is that minute.

Air intake clamps shouldnt be a big deal... its after the TB where the vacuum would make a difference. Didja reuse your TB gasket? I know they can be a pain to get off... and seem OK to reuse...

No. I used 2 new ones. 1 for the RBC/Karcepts & then another new 1 for the Karcepts/EP3 TB.

The day I last posted on this thread though, is the day that it stopped idling weird. I didn't do anything but it's back to normal. Idk what the deal is..

iDom

08-22-2012, 07:50 AM

Did a few things and so far so good.

First thing, I noticed that my PCV valve hose that went to the manifold was at an awkward angle and pinched shut, so I replaced that.

Second, my auto tensioner/idler pulley went right as I was turning down my road last week so I replaced it last night once the part came in. The bearing was shot and was cause a lot of strait on the pulley assembly bogging the engine down. As of now, I have had zero idling issues. I'm not sure which one was the main source (I'm thinking the PCV) but, I'm in the clear now and the K24 is running great. A bit on the rich side, but I have yet to get it tuned