Rough Idle at Start Up, Stop Lights, etc

[VaTechZHP]

I can't vouch for the cleaner ICV, but I know for a fact my DISA valve was toast. I replaced that and the car is idling great again. I had small cracks in the lower intake boot as well, but the DISA was completely shot.

Regardless of fixing the other pieces, having that broken DISA made the car act the same.

Did you do these things one at a time such that you could vouch for which one solved your idle issue?

[M3TA5IN]

Funny I'm going through same exact issue with the jeep gc. Right as we were getting ready to sell it.

Pretty sure I have it narrowed down to bank 2 #1 O2 sensor, going to replace tonight.

[echo46]

In my opinion, if you are experiencing idle issues, you should methodically address easiest to hardest as follows:
1. Check for codes
2. Check upper and lower intake boots
3. Clean ICV
4. Clean MAF
5. Clean Throttle body
6. Check DISA for vacuum leaks and functionality
7. Check CCV and all its annoying hoses including oil stick tube
8. Check fuel pressure at the rail
9. Check fuel lines for small leaks.
10. Check Fuel injectors for O-Ring leakage or injector leakage.

Can't think of anything else but if I miised something the experts will chime in.

[danewilson77]

Yup. And 1-6 should be done together imho.

Sent from SIGFest 2012

[echo46]

As long as you have everything off for 1-6, you should check CCV for leaks and the infamous OFHG for leakage. It just never ends.

[MrMaico]

This is a good thread about one specific CCV hose that can cause idle problems and certain codes. Good info to bookmark.....

http://forum.e46fanatics.com/showthread.php?t=773551

And another good thread with lots of info......

http://forum.e46fanatics.com/showthr...6&highlight=50

[Oli77]

^ good stuff indeed. Thanks.

[aurelius]

There's a LINK TO DISA O-RINGS in that 2nd e46f thread posted above. Read the DISA sub-section in that post and if you think yours is still good (after removal, inspection, shaking it, etc.), consider a new o-ring. I did the electrical tape thing but I'd prefer to have a proper seal in place to avoid any vac leak.

[echo46]

I too did the electrical tape half asser, just for some assurance eventhough I don't think mine was leaking. WIth the electrical tape it does fit in there nice and tight. Should probably just get a new O-Ring.

[danewilson77]

There's a LINK TO DISA O-RINGS in that 2nd thread posted above. Read the DISA sub-section in that post and if you think yours is still good (after removal, inspection, shaking it, etc.), consider a new o-ring. I did the electrical tape thing but I'd prefer to have a proper seal in place to avoid any vac leak.

I put this in my diy thread. Thanks brah.

Sent from SIGFest 2012