amandamarie

2003 CL type S
So. Around Nov of last year, my car started idling at 1200rpm. In January i replaced the IACV. Didnt fix it. Replaced MAP sensor. Ran Seafoam. When i would be in neutral (its a manual) and rev it, it would drop back down to normal idle. Finally got around to completely taking the intake apart and cleaning it. Found that nice lump of coal inside the intake. Checked the injectors while i was at it. Put it all back together, and it started up just fine. Started driving , and the idle started getting stuck at 1500rpm. Then 2000. Then fluctuating. So. Get on the highway, give it some time, get off the highway. Stuck at 1500. Bought new wiring harness because it wasnt fully clipping to the IACV. Nope. Bought a new IACV from parts authority. Nope.

Today. At cold start, the idle is fine. Mostly. Sometimes it sits at about a 800-1000 whatever. I Drove it through the city streets to get to the highway and it was mostly fine. It stuck at about 1500 RPM at idle eventually, then I got on the highway. I ran it pretty hard. I took it out of gear, and it would fluctuate up and down, then again at 1500. When I got off the highway to get gas to put the seafoam in, it got stuck at 3500 at idle. 4000 at one point. I don't even have to use the gas peddle to drive it. It's like the throttle is stuck open or something. I got back on the highway and I ran it in higher gears as to not use the peddle as much and just let it go on its own in hopes the idle would be at least back down to 1500 when i got off the highway, which seemed to have worked. I didnt get on it, I was very gentle with the gas peddle. When I got back off the highway to city streets again, it was idling at 1500-1700. I never touched first gear again. I barely had to give it any gas to get it to go in second and I didn't have to give it any gas to drive 25mph.

I sprayed for vacuum leaks to no avail. This wasn't a problem before I took it apart to clean it. Before and after i cleaned it kept getting P0505 code. I made sure to bleed the coolant as well.

On cold start it still is normal idle. On warm start (without driving it) idles at 1500 or fluctuates.

zeta

iTrader: (1)

Not sure if this is the issue; however, it appears your gray EGR connector is not fully engaged / seated on the EGR unit?
You can tell by the space and the connector clip looks pushed up?
Also check the 'pins' on the male EGR connector side?


The one below displays the EGR connection on my CL-S6:


In addition, if you are not already doing it, one should perform the 'idle learn' procedure per the below:
Since you installed a new rotary air control valve, let the ECM ldle learn anew.

Good Luck.

amandamarie

Update. I replaced the throttle body from a junk yard. It came with the original sensors from the junk yard. Same problems.

I replaced the junk yard IAC with the new one I had from Parts Authority, tested the MAP and TPS. MAP was good, TPS was just slightly off on voltage. Bleed the coolant. Same problems. Held my fingers over the IAC inside the throttle body while stuck at 2000, no change.

I replaced all the gaskets on the upper intake and throttle body. Seemed to be ok at idle and when I revved it. Didn't get stuck. Took it for a run on the highway. Stuck at 3000 grand.

Sat to think and looked for just "throttle stuck" this time, and all whole bunch of stuff about auto trannys. Then someone mentioned the cruise control, and I had watched a YouTube video a while ago where a van had a high idle and the guy just had to adjust the cruise control cable and the problem went away but it didn't really, seem to have the same idle problems as mine. The guy couldn't even get it to start cold because the idle was so high cold.

So, F--- it.Removed the cruise control cable. Problem solved. I just whipped it around a couple highways for a good 45 minutes.

I don't know if it was because the insert where the cable head goes is slightly damaged or if I have a wiring problem. My passenger side headlight is out, despite changing the bulb twice, and on that same side sometimes my speakers go out for a second when I hit a bump(sometimes), and that is also where the cruise control computer actually is. All in that same area. So maybe I have a wiring issue. I'll find out later, but after all the cleaning and replacing and everything else, my car runs like a champ. Idle is perfect, shifts great, power is great. I should be irritated, but after all the time and energy and maybe $400 I spent on it, I am really really grateful it's fixed. Like I use cruise control anyways