Jump to content

- - - - -

Can Bad Egr Valve Cause High Idle?

This topic has been archived. This means that you cannot reply to this topic.
1 reply to this topic

#1 stu1962



  • Member
  • 24 posts

Posted 14 November 2009 - 01:55 PM

93' Suburban 2WD.

Recently had issues (see my previous posts) with ignition issues and believe I have solved that.

Now that I believe I have that solved, I hear a very high pitched vacuum leak. Have isolated that whistle to the EGR valve...can squeeze the diaphragm from below the valve and whistle goes away...so, assuming EGR is leaking vacuum.

Question is, my burb is idling 1000-1100 rpm or so...smoothly. I am also continuing to get code 35 (Idle Air Control). Can a bad EGR cause these things? high idle/code set 35?

#2 Nytemare


    Senior Enthusiast

  • Member
  • 4,417 posts
  • Location:Victoria BC
  • Gender:Male

Posted 14 November 2009 - 02:29 PM

Sounds about right. Time for a block off plate....If you don't have emissions laws where you are.

If you have a Vac leak, you will either idle high or rough. High idle will cause it to not idle rough for the most part.
Disconnect your Positive batt terminal for 2min to reset codes, pin the EGR valve diaphragm up with a clothes pin or something similar and let it run to see if the code returns.

Or you can pull the vacuum lines off the EGR and just plug them off, and see if your code returns.

Edited by Nytemare, 14 November 2009 - 02:33 PM.

Posted Image

so you expected something that weights 5000 pounds and has aerodynamics of a piano to get what?

2003 Silverado XCSB, 4.8L, Flowmaster super44 SI/DO, G80 3.42, MSD Wires, K&N drop-in filter, Yellow Top Battery, Royal Purple in entire Drivetrain, W4M tune....My DD..............................SOLD
2010 Silverado XCSB 5.3L Z71 Summit White, Diablo Trinity tuned....more to come soon.
2010 Cobalt 2.2L LT 2Dr. Victory Red....gas saver/wife's Car.......SOLD
2011 Cruze 1.4L Turbo 1LT Crystal Red ...Again, Wifes car and gas saver
1978 LJ80, 16V 1600cc on 31's, Spring over lift, awaiting Full Frame off build...The Toy