QuestionThere is no hesitation or loss in power when I accelerate at full throttle. Could I still have a fuel pressure problem? How easy is it to replace the EGR or IAC valve? I have done a decent amount of work on cars, but never on those parts. Thanks for the quick reply.
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I have a 1990 Blazer that I purchased recently. It has 169k miles on it, and has hardly any issues. The one thing I have noticed is that while in Park, the idle is lumpy and it seems like it almost stalls. It happens also when I am in Drive/Reverse and stopped, but not as severe. I plan on checking the Idle Air Control valve, but is there anything else I should look for? Thanks!
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The idle air would be my first suggestion, but a dirty EGR valve, and low fuel pressure would be close behind.
Van
AnswerActually, it would be possible to have low fuel pressure, and still run pretty good, but the pressure check was low on my list, and it is a pain to do on vehicles before they added the test ports.
Egr is simple to remove and clean, and is actually a regular service recommendation.
The TPS is easy to change, but I would test it first.
Best way is with a scan tool, but you can check it with an ohm meter. You just want a consistant and smooth change of reading throughout the travel.
A vacuum leak is another thing to search for. That is what the EGR valve creates if it closes on some carbon.
But if your problem seems to act up more when the brakes are applied, there may be a leak in the brake booster, unless you have the hydraulic booster.
Van
