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I went to get an emissions test for my 91 6 spd for the local smog police and it failed the high speed test. I replaced the EGR valve and reset the computer. I drove a total of 35 miles and the light came on again. This time I checked for vacuum leaks on the EGR valve but found none. The car drove great before the light came on but after that it sparked knocked on the 1-4 shift and ran rough. What gives? Am I missing something here? Any help would be appreciated.
I'm not sure if the '91 is the same as my '89 but if it is, try changing the EGR temp. switch. It is located on the EGR pipe (goes from engine to exhaust manifold). The part is only about $10 at the dealer and takes about 3 minutes to swap out. I'd try that first because the solenoid is about $30. Anyway, this cleared my 32. :yesnod:
If the $10. doesn't fix it then run a check on the soleniod. The procedure for my 92 is probably different than yours however. You need a good manual like Helms for the car which will tell you how to run diagonistics.
I may be wrong but I have never seen an EGR switch on mine. There is not one in the EGR riser pipe. I had code 32 but it was because of the dual exhaust I installed, but it ran ok with or without the light.
I went to NAPA yesterday and ordered the solenoid($19.99) and it should be here today. This still beats going to the local mechanic and paying $70.00 per hour for his labor. :smash:
My 92 is located at the left rear on the intake. Your' is probably different. Just follow the vac. tube from the EGR and it should lead to the soleniod.
Where is it located on the car? Is it the round valve under the plenum?
Yes, that's the EGR valve. I don't know if the archives go back far enough, but there was a discussion about these. Supposedly some of the aftermarket EGR valves don't operate the way the GM original (and GM current replacements) operate. There is at least one guy here in C4 who installed one from his local parts chain and couldn't get it to function properly. When I put the GM one it, it fixed the problem. Personally I put a GM one in my '87 and have had no problems since. Make sure you get all those little vac lines on the underside of the plenum hooked up or it'll run wierd. ;) Don't ask me how I know that. :D