is it suppose to be like this?
#13
alrighty, i just had a very similar problem with my blazer today. i replaced the clogged egr valve screen yesterday. one my way home from work, chunks of carbon broke free on the highway and made the egr valve stick open. it caused it idle horribly, i had almost no brakes, and it would surge like it had a super huge cam in it. but as soon as i was about 10 mph or faster, i had no problems at all. im thinking you might be getting a vacuum leak into the exhaust passage, causing it to sound like it. my 4.3 blazer sounded EXACTLY the same as your car.
Last edited by microkid; 11-27-2009 at 07:04 PM.
#14
im thinking u have a carb, if so try setting the idle up and lean your idle screws. it may need more air. if that dont work then i would say u have a vacumn leak somewhere.
#15
alrighty, i just had a very similar problem with my blazer today. i replaced the clogged egr valve screen yesterday. one my way home from work, chunks of carbon broke free on the highway and made the egr valve stick open. it caused it idle horribly, i had almost no brakes, and it would surge like it had a super huge cam in it. but as soon as i was about 10 mph or faster, i had no problems at all. im thinking you might be getting a vacuum leak into the exhaust passage, causing it to sound like it. my 4.3 blazer sounded EXACTLY the same as your car.
#16
the egr valve on mine has two ports, one to the exhaust, one to the intake manifold. at idle when its under vacuum, it was sucking in the exhaust and severly diluting the mixture, causing it to misfire and surge badly. im not sure how your intake it set up on the egr valve, but it could be doing the same. and since that was the only thing you changed, its rather likely that is the problem
#17
To me it sounds like the timing is too far retarded. Either that, or you have the firing order wrong. You should be able to move the distributor back and forth quite a bit without it stalling out...
#18
the egr valve on mine has two ports, one to the exhaust, one to the intake manifold. at idle when its under vacuum, it was sucking in the exhaust and severly diluting the mixture, causing it to misfire and surge badly. im not sure how your intake it set up on the egr valve, but it could be doing the same. and since that was the only thing you changed, its rather likely that is the problem
#19
hey, no problem. although, it would be nice if you paid the ticket i got when my egr valve failed. couldnt get out of the gas going down the mountain, and had no vacuum to the brakes. its only $110. haha, its alright. live and learn