Does the EGR relate to surging?

[90mustangGT]

I've always had a surging problem when I first crank the car up when it is warm. Well, when I did all my fuel upgrades, I broke the vaccume line that went to the EGR, now I don't have this problem. I have heard this before, but now I am thinking of doing a EGR delete. Now I have a "check engine" light but the kits are suposed to end that problem.

Who makes a good kit? The one that covers were the valve goes and has the plug that keeps the light off?

 

[PRO50SC]

Have you ever checked to see if there is vacume present in the line at idle? If so, this is why you have a surge at idle. There should be no vacume at the valve at idle. If there is, you probably have a bad egr solenoid. Or maybe the upgrades took care of the problem.

 

[90mustangGT]

That is a thought I never crossed my mind, but another question. The EGR is hooked to the vaccume lines, so shouldn't it get vaccume when the engine is making vaccume. At idle I get some vaccume.

 

[Michael Yount]

THe egr valve isn't hooked directly to manifold vacuum if it's hooked up properly. The egr vacuum line should come from the egr switch on the firewall; the egr switch is connected to engine vacuum and to the wiring harness. The computer tells the switch when to allow vacuum to go to the egr valve. At idle and wide open throttle, the egr valve should be closed - which means there's no vacuum at the egr valve at idle or w.o.t. THe computer only directs the switch/valve to operate under part throttle conditions. Go to www.ronmorrisperformance.com for more info on egr delete kits.

 

[jerry beach]

I've always had a surging problem when I first crank the car up when it is warm. Well, when I did all my fuel upgrades, I broke the vaccume line that went to the EGR, now I don't have this problem. I have heard this before, but now I am thinking of doing a EGR delete. Now I have a "check engine" light but the kits are suposed to end that problem.

Who makes a good kit? The one that covers were the valve goes and has the plug that keeps the light off?

Thanks for bringing this up. That is something I have not checked on mine. I still have the surge on warm starts too. Levels out after a few surges and idles steady. And Michael, thanks for all the great info, as usual.

 

[90mustangGT]

Michael: Mine got it's vaccume from the little 5 prong vaccume harness on the passenger siden not from the firewall connecter as you mentioned. Maby I should hook it up right, or better yet, delete it.

Thanks for the input everyone

 

[Michael Yount]

90 - yeah, I'd try straightening that out. If you disconnect it from the valve at idle - nothing at all should happen - there shouldn't be vacuum on the hose you pull off the valve - cause at idle the egr switch won't let vacuum through. If you pull it off at idle and there's vacuum on that hose, that means your egr valve is operating anytime there's vacuum - and that will definitely cause issues. Good luck with it.

 

[PRO50SC]

The egr solenoid on my car (92) is mounted on the rear of the passenger side strut tower not on the firewall. You should check to see if yours is mounted there before changing anything.

 

[Michael Yount]

Pro50 - thanks for clarifying; I sometimes forget that during the transplant of my engine, some of the extracuricular equipment got mounted in slightly different locations than in the Stang. My egr switch/controller got mounted in a convenient spot on the firewall - it sounds like right across from the back of the strut tower where it is on the Stang.