I was wondering If someone could enlighten me as to the purpose of the EGR valve on a 302W and what would happen if it was removed. The motor I recently installed has the EGR pipe cut and shut. How does this affect the running of the engine? The engine lopes badly at idle when first started but I'm presuming that's the IAC ( will change tomorrow ).
cheers

 

The EGR is part of the emissions control system. Your truck runs really lean at cruise speed on the highway, and lean mixtures explode very violently, producing a lot of heat. Lots of heat means increased production of NOx gases, which are bad for the environment. The EGR introduces a little inert gas (exhaust gas) into the intake so it doesn't burn as hot. It reduces the amount of fresh air and fuel making it into the combustion chamber.

If it's not working, it depends on *how* it's not working. Since the pipe is only an intake, what will happen if it's shut on the EGR valve side is the valve won't be able to put any exhaust gas into the engine. But the computer will still think it's open and add fuel accordingly. This will result in increased NOx gases and lots of driveability problems, including rough idle, pinging, bad fuel mileage, easier to overheat, etc.

Overall, not a good thing.

 

andym, Ta dude. Shall swap EGR pipe with old motor before it goes.
Cheers