Mechanics

EGR ISSUE

1998 Chevrolet Silverado • V8 4WD Automatic • 119,500 miles

I have a 98 Chevrolet Silverado. I had the fuel pump replaced. On the way home it felt as if the fuel was not being regulated and the throttle was surging. The service light came on and it came up with an EGR code. I tried cleaning the existing EGR valve and put it back on. I got the code to go away and the surges seemed to stop for the most part. However, now it has hesitation on take offs. I bought a new EGR valve, replaced it and the whole truck starting idling horribly and would almost die when gas was applied. I put the old EGR valve back on and drove it a few miles and got a service light. Had it checked at Autozone and it said EGR Closed. I took the EGR valve I had bought back and got a new EGR valve and put that one on. Did the same thing while idling. I noticed the gasket was a little bigger around the bolt holes, so I used the old gasket with the new EGR valve, and the idle is now fixed, however I still have the hesitation on take offs. Is it possible the gasket is still not 100% tight? Is it due to the fuel pump? I never had any issues until the fuel pump was put on. Im really frustrated with this. After putting on the EGR valve with the old gasket, the light had come on, but then went off. Hope you can help me. I have a 5.7 350 4x4 Silverado 1998
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Ratizzle
August 10, 2011.




Have you solved it? Did you take back to pump installer for checkup? Check for vac leaks clean MAF?

Tiny
Fixitmr
Sep 11, 2011.
I have a 98 Silverado 4x4 with the exact same everything! New fuel pump and filter, EGR codes and rough idle when cold. Replaced EGR and no fix. Same problems. Have you fixed the problem? I am baffled and dont have a tech2---
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Tiny
Bgil6773
Feb 8, 2012.
Does it hesitate both cold and warm?

Tiny
Fixitmr
Feb 8, 2012.
Does your EGR have vacuum line? Try disconnect and plug hose. If that helps then egr solenoid is defective.

Tiny
Fixitmr
Feb 8, 2012.
No EGR vacuum lines. All electronic. Only hesitates when cold. Hit the gas when cold. Stumbles and almost dies. Once going runs well. Horrible fuel mileage now too. Fuel pressure is perfect and within specs.

Tiny
Bgil6773
Feb 9, 2012.
It's running fine warmed up? If you trounce it does it blow black smoke?

Tiny
Fixitmr
Feb 13, 2012.

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