EGR Valve on 88 TBI 350... What happens when it goes bad?

[foxman]

Mycheck engine light comes on only under constant highway speeds @ 60-65mph. Usually does it when towing. The only code present is the EGR code. I replaced the EGR Solenoid and made no difference. Should I look at replacing the Actual valve?

Thanks for any info.


Jeremy

 

[Grim-Reaper]

Sounds like the passages are clogged.

Confirm the valve is opening. There is usualy some holes in the bottom and you can feel the diaphram lift when you apply vacuum. Some of these EGR'S bleed off and you will not be able to check with mighty vac. You will have to have the engine running and by pass the solonoid to direct vaccum to do this test.

Second test and possibly the first is to hit the EGR with direct vac at idle. It should start stumbling and possibly stall.

If you confirm it's opening and then don't get the idle issue while you test at idle then you have a clogged port.

 

[K5MONSTERCHEV]

What Reaper said! /forums/images/graemlins/thumb.gif