How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask GMTechBernard Your Own Question
GMTechBernard, Shop Foreman - GM World Class Tech
Category: Chevy
Satisfied Customers: 2158
Experience:  GM
Type Your Chevy Question Here...
GMTechBernard is online now
A new question is answered every 9 seconds

91 chevy: rough idle..acceleration..I first start my truck..EGR valve

Resolved Question:

My 91 chevy pickup has a rough idle and sluggish acceleration when I first start my truck after sitting usually smothes out after driving 10 to 15 min. Could this be my EGR valve or something else
Submitted: 9 years ago.
Category: Chevy
Expert:  GMTechBernard replied 9 years ago.

It coult be EGR related, and one way to test for that, is to take a soda can and make a gasket for it. Just trace around the outside of the valve and cut it out. Cut out the bolt holes and a hole for the pintle, but do not cut out a hole for the other passage. Put it back together and if the problem persists, its not the EGR valve.

If not the valve, then you need to look closely at the fuel system. These systems need about 12-13 PSI and when the pumps get old, they might put out 8-10 which can cause minor issues. Also, between the pump and the sending unit, there is a short rubber hose that likes to split, or if it has a pulsation dampner instead, sometimes they don't seal right and can be replaced by a short section of fuel hose.

One other thing to look at is the distributor. Remove the distributor cap and look at the toothed wheel underneath. If there are any cracks in it, or the coil around it, it will need to be repaired.

Hope this helps, and feel free to ask more questions if needed.

GMTechBernard and other Chevy Specialists are ready to help you