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Discussion Starter #1
Hello everyone I got a P0507 code today car started acting up last night did a bunch of reading I'm going to clean the throttlebody thinking about taking it out of the car to clean thoroughly and there's another part in there that I need to replace or want to replace rather what else should I replace if I'm that far into the motor? I already cleaned and replaced the IAC valve about a month month and a half ago. And I was going to check all around for vacuum leaks.

Mike
 

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if you want help, first thing after pulling codes post them on the forum WITH DEFINITIONS. See sticky at top of page on how to pull codes--it gives a link to the definitions. Someone will chime in with helpful suggestions.
 

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Master of the Dark Art of Diagnostics
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Hello everyone I got a P0507 code today car started acting up last night did a bunch of reading I'm going to clean the throttlebody thinking about taking it out of the car to clean thoroughly and there's another part in there that I need to replace or want to replace rather what else should I replace if I'm that far into the motor? I already cleaned and replaced the IAC valve about a month month and a half ago. And I was going to check all around for vacuum leaks.

Mike
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yup - ALWAYS include DEFINITIONS along with the codes -
no one has them all memorized -
and everyone looking at this thread will either have to stop -
and go look it up -
or simply bypass it -

thinking about taking it out of the car to clean thoroughly
no need to remove the TB to clean it -
 

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P0507 - Idle Speed High

You need to eventually change your IAC. Same thing happened to mine, cleaning the TB is always good but cleaning the IAC is only a temporary solution that will probably only last 3-6 weeks - as per my experience
 

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Master of the Dark Art of Diagnostics
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P0507 - Idle Speed High

You need to eventually change your IAC. Same thing happened to mine, cleaning the TB is always good but cleaning the IAC is only a temporary solution that will probably only last 3-6 weeks - as per my experience
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You need to eventually change your IAC

a failed IAC should set a code -
and - this from post #1 -

I already cleaned and replaced the IAC valve
about a month month and a half ago.
 

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You need to eventually change your IAC

a failed IAC should set a code -
and - this from post #1 -

I already cleaned and replaced the IAC valve
about a month month and a half ago.
but does that mean he cleaned & put it back, OR installed a new one?
 

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Discussion Starter #9 (Edited)
Oh good grief I'm sorry I read so much and I forgot about that little rule. Just got back from driving the kids around daddy the taxi driver in my other car.

I had gotten a different IAC valve off of a 2001 Deville with 63,000 ish miles from the junkyard. I did do the relearn procedure on it of course I cleaned it before I put it in. Drove around for a week worked great. cleaned my original one put it back in the car did relearn procedure and it started acting up again in two or three days. So put replacement one back in (relearn) and that was about 1.5 months ago. And yes one I got at junkyard was acdelco.

From all the reading I did last night, I was thinking about doing the plenum replacement (http://www.cadillacforums.com/forums/cadillac-tech-tips-how-fix/171319-2000-northstar-plenum-replacement-steps.html) Since it is hard to see if it is really leaking or since it is a common place to break.
 

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Don't start throwing parts at it. If you suspect the plenum duct, check it, but it won't throw that code. It'll usually throw a P0171 & P0174. To check it, spray it at the bottom (6:00 position) with Brakleen or such while at idle. Flex it with your finger while spraying and listen for an RPM increase. If the RPM increases, the duct is ripped.
 

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After messing around with two junkyard IAC motors, recently having crazy (rolling up and down & stalling) idle control issues on my 2002 SLS...I stumbled on something that ended up being the cure and I've never seen it mentioned on this site. Ends up, the IAC being dirty isn't the big issue, but the PINTLE VALVE that comes LOOSE!

While sitting at my bench in the garage contemplating how I got two bad IACs in a row, I just happened to twist hard with my fingers on the end of the valve and it came loose. Light bulb went on and I began screwing it all the way out. It's on a threaded rod and over time vibrations must cause it to loosen and turn itself out. I even thought about putting a dab of Loctite on the threads.

Turned it all the way back in until it was seated, and replaced it. After a short re-learn and a couple of starts...presto, the car starts up and runs exactly as it should. No more stalling or rolling idle...and this has been the case for three months now. This was on my original IAC, and it barely ran with this one before and after cleaning.

So, do not bother buying an expensive new IAC valve! Try this first. and just clean it and tighten the pintle back in and everything should be back to normal within a couple of key cylcles and some run time. Good luck!
 

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What re-learn procedure did you use? I've seen various ones on the forum ranging from putting the car in revers for 10 minutes, etc
 

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Discussion Starter #13
centaur said:
After messing around with two junkyard IAC motors, recently having crazy (rolling up and down & stalling) idle control issues on my 2002 SLS...I stumbled on something that ended up being the cure and I've never seen it mentioned on this site. Ends up, the IAC being dirty isn't the big issue, but the PINTLE VALVE that comes LOOSE! While sitting at my bench in the garage contemplating how I got two bad IACs in a row, I just happened to twist hard with my fingers on the end of the valve and it came loose. Light bulb went on and I began screwing it all the way out. It's on a threaded rod and over time vibrations must cause it to loosen and turn itself out. I even thought about putting a dab of Loctite on the threads. Turned it all the way back in until it was seated, and replaced it. After a short re-learn and a couple of starts...presto, the car starts up and runs exactly as it should. No more stalling or rolling idle...and this has been the case for three months now. This was on my original IAC, and it barely ran with this one before and after cleaning. So, do not bother buying an expensive new IAC valve! Try this first. and just clean it and tighten the pintle back in and everything should be back to normal within a couple of key cylcles and some run time. Good luck!
I ended up leaving the throttlebody getting my RPMs back down into an acceptable range but now it was idling at 650 I put it in drive or any gear other than Park or neutral and it would then go to 475/500/550 rpm's doesn't stall. But runs at the lower rpm's I'll definitely give this a shot thank you for the idea.

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Alifard said:
What re-learn procedure did you use? I've seen various ones on the forum ranging from putting the car in revers for 10 minutes, etc
I did a short one which was start the car for 15 seconds put the key back into the lock position wait 15 seconds restart the car. I found it in a couple times so I used one that I found multiple places.

And since then I now get p0506 code. Idle Air Control System RPM Lower Than Expected

Read more at: http://www.obd-codes.com/p0506
Copyright © OBD-Codes.com
 

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A pintle is a tapered or graduated movable "plug" that, depending on how far in or out of a hole it is positioned, allows more or less air or exhaust gas (depending on valve application) to pass from a high pressure area to a low pressure area.

In the IAC case the valve position controls idle air bleed. It's the silver/black small can on the left (front) side of the throttlebody casting. 2 Torx or Philips screws. Clean it carefully and insure the "top hat" pintle is threaded tightly onto the operating shaft.

Atmospheric pressure pushes air into an engine at a rate determined by several variable opening sizes. The IAC or ISC controls the amount of air fed to the idle circuits - more air = faster idle (basic, basic statement that leaves out fuel requirements). An engine does not "suck" air into the cylinders - air is pushed in by atmospheric pressure. Naturo abhorret a vacuo.

Get into RockAuto, your car/year, fuel/air, and look at the pictures of several IAC assemblies. (Click the little picture or INFO tab for a zoom and other views of the IAC.)
 

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Discussion Starter #16
I tried the unscrew iac today. Before I did it I looked at valve closely. It has a little play say about 30 degree back and forth spinning with finger. So I decided to unscrew it. Had to put some muscle to loosen it. And unscrewed it all the way out. Seems to have the threads mentioned. And looks like where it screws into cracked slightly to allow it to spin/unscrew out. Not circle but above the threads were 2flat sides that must be used to keep from spinning unless told to. So I screwed it all the way back in. Showing that crack as threads went in further and further. I'll take it apart again tomorrow and get pictures (I remembered after I put back into car.). Idle seemed little higher. Jumped around 675. 700 750 775 800 at idle. Higher than the 475 ish I was getting. So as not to leave me stranded I picked up another 5 dollar used iac valve from 2004 DeVille at junkyard. Will clean it and put in.

And in other news finally got drivers mirror today. I've been attempting to get one here in Cincinnati at one of the multiple junkyards for months and finally one was available when I went to go to the car. I have even had the experience of a car that had been there two days I show up there to look for the mirror and someone is there taking the mirror I wanted off the car I congratulated them for beating me to the part. :)
 

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Discussion Starter #17
Here are the pictures.

http://i1175.photobucket.com/albums/r621/mike120/Mobile Uploads/2015-03/C2AE3008-DA10-4276-9F10-A1C29C6E5E5B_zpszqfonx4o.jpg
http://i1175.photobucket.com/albums/r621/mike120/Mobile Uploads/2015-03/2ADFD870-AAAD-4FA1-BE83-4FD73C9BA965_zpsamvj4ocm.jpg
http://i1175.photobucket.com/albums/r621/mike120/Mobile Uploads/2015-03/827D9CD2-6695-4B6E-94F6-397F95419037_zps0uafe1id.jpg

So I took it all apart again last night took pictures cleaned it better and put it back in did the relearn procedure and seems to run perfectly drove for about 10 miles idles at 6:50 or 675 in neutral and park put it in drive I'll does not change where it was previously in my service engine soon light even went awaywithout even clearing the codes. If anything changes I will update the thread.

Thank you all for your assistance
 

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I just tried this lil fix and seems to idling and not stalling at slow speeds. This is one I got from ebay for 9 bucks, worked great for a few months then started acting up. Now on to the head gasket issue.
 
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