ok guys i need some suggestions/help/. ive read others threads about this code and dont the necessary steps to diagnose it. (i think)

for those who dont know P0507 is the "engine idle higher than expected"

everyone keeps saying its a bad IAC so i checked that by trading a friend and using his. But no go.

My idle is still jumpy.

also now sometimes when im in a gear at a low RPM the car engine sputters and jerks almost like it wants to die.. then it picks it up and starts accelerating like normal... im very confused and again everyone keeps saying iac and vacuum leak which ive checked both.

any other suggestions?

 

oops somehow i put this in the wrong section. Mods move sorry :/

 

I've got the same issue that just came up...did you find a solution?

 

Boost leak test after the tb? Perform a BLT first and see if you can find anything obvious.

 

I have the same. replaced IAC. still the same. great. now what?

 

ok, so, I checked the hose on EGR and everywhere else and I cannot find anything loose.

from here: http://www.obd-codes.com/p0507

"A P0507 DTC trouble code may be caused by one or more of the following:
•Leaking air intake after the throttle body
•EGR valve leaking vacuum
•A faulty positive crankcase ventilation (PCV) valve
•Damaged/failed/dirty throttle body
•Failed EVAP system
•Failed IAC (idle air controller) or faulty IAC circuit"

could my PVC being stuck open cause my idle to go high (2200 RPM)?

to test it do I just remove it and blow through it and see that it blocks air one way and allows air the other?

There's nothing there about the MAF but i've heard recommended here to clean the MAF for this code. Does that make sense, I guess after PVC it's the next easiest thing to try.

Spent 80.00 on an IAC that I may not have needed and I can't be bothered to take it off to return it seeing as how beat the one I took off looked, I'd likely end up needing it soon anyway.

I have 80K miles on the car and have no clue when the PCV was last serviced.

Oh yeah, I checked and there are no other codes. This happened suddenly at the end of 90 mile drive.

 

Did you do a boost leak test? PCV valves are not expensive or hard to replace. Could the throttle body shaft seals be leaking? Maybe one of the vacuum lines on the back of the intake manifold popped off?

 

doh! no. sorry.

I know that's the first thing you should do. rather than go hunting snipe under the hood like a 'tard.

and I even have the tester, just need a few inches of 3" silicone to attach it to the turbo.

the throttle body looks solid as hell, it's a new full-blown 70mm , installed by CBRD only about a year ago to include a boost leak test and some work on the seal, I think.

I'll do the boost leak test and post the result. thanks very much.

 

run idle stepper function in evoscan- and adjust throttle screw-

see if that helps-

cb

 

thanks chad. I need to get the damn tactrix cable still... DOH!

 

Cleaned my PCV valve, it was definitely dirty and gunked up and didn't move easily.

My new concern is that I've read you should always go OEM with PCV valves and comparing it to what's advertised by STM here:
http://www.streettunedmotorsports.co..._pcv_valve.htm


It doesn't look OEM to me, this came off my car:
http://www.flickr.com/photos/9969131@N03/8706607013/http://www.flickr.com/photos/9969131@N03/8706607013/ by http://www.flickr.com/people/9969131@N03/, on Flickr

It is attached with a 90 degree coupler of some sort you can see here:
http://www.flickr.com/photos/9969131@N03/8706608407/http://www.flickr.com/photos/9969131@N03/8706608407/ by http://www.flickr.com/people/9969131@N03/, on Flickr

Does that look OEM or should I skip the BS and go get me one from the dealer?

[UPDATE:]That's what I did.

 

I confirmed that I had the correct PCV valve... by putting a new one in that I bought at the dealer.

Then I did the Boost leak test:

After:

When I started the car up the P0507 and high idle lasted another 2 days before the computer sorted it out, the CEL went away and it's idling at 1000 on the dot. And now that I've fixed that leak the diverter valve seems to be functioning more exactly/smoothly. Car drives better now than it did before.

I've got a tactrix cable on order and I'll do the BISS adjustment when it comes in just so it won't take the car two days to get sorted every time I reset the ECU.

If I had just taken this problem to a mechanic and thoughtlessly paid the bill it would have come to $400+. Instead I paid 100.00. Winning.