Quote:
|
Originally Posted by channer Is there a way to check if the EGR system is blocked? Would it still run rough if blocked. |
#1 you already checked the EGR ports. By lifting up the valve by hand and the car stumbled/died the port is open.
#2 lift up the valve. Remove the vacuum line. Put your finger over the nipple (
) of the EGR while holding it up. If the valve staus open the diaphram is good.
#3 put a vacuum gauge in line with the EGR. Use a Tee. Go drive it. Do you get vacuum at at steady state cruise? If so, the computer,chip, and EGR solenoid are all working
If the test above all pass then the EGR system is not the problem.
A catalytic converter will flow fine and look fine but not work fine. We use a number of things but an infared temp gun usually works best. The outlet should be a minimum 100* F HOTTER than the inlet of the cat at 2500 rpm.
Looking at your numbers I'd look at the EGR valve first. GM is notorious for popping diaphrams. If you decide it is the valve itself that's bad PLEASE buy a GM part. The part number is stamped on the top
Good luck. Maybe you should find a "buddy" shop that'll "test" it for a little extra "gratuity"