: 79 Seville 5.7 EFI Cal Emissions Equipment.

06-07-08, 10:49 AM
I read somewhere in this thread I think, someone bypassed all the emissions sensing equipment and retimed the engine and all worked great. I can't find the thread, sorry if this is a duplicate. I have bypassed the EGR solenoid, the fuel economy switch and the distributor solenoid in my car already. I have not disconnected the ESS module, I thought it was too drastic a step? The engine performs fine except to some minor detonation or puffing when it's cold or during times of very rapid acceleration. If I disconnect the ESS and retime will this go away? As a lesser issue what happens to the gas milage, not concerned since I realize I am driving a Cadillac. Enjoy the car very much, fun drive.

06-10-08, 11:03 PM
Those don't sound like improvements. GM already maximized the power and economy on this engine if everything is working right. I think the only room for improvement would be to free up the exhaust a little. Enjoy the cool ride.

06-12-08, 10:06 PM
Removing emission equipment on that car will only make driveability worse. By the late 70's emission items were designed into the engines not like the late 60's when they were still experimenting! EGR disconnected will just cause the car to ping. The fuel economy switch simply lit up the amber and green lamps in the dash, did not affect power. Leave it all alone, bump the timing up a couple of degrees, install a free flowing exhaust and a less restrictive cat. converter. You are using a 60's mind set on a late 70's car!