I have an 88 fhp mustang and i got it couple of months ago and the smog pump i took off and i noticed the EGR had no vacum line going to it and it is unpluged. I pluged it back in but not the vacum line because i dont have one and i dont know were it goes to. But the car ran better but got worse gas milage. The car runs fine with it unpluged. I didn't know if anyone has an ideas for it.

 

I would just plug it in and leave it you you dont go into limp-home. But you are getting exhaust in the engine at idle.

 

When the egr vacuum line is unplugged, the valve stays closed at all times. From an engine standpoint, this is a good thing.

When in deceleration, you have a lot of fuel dumped into the cylinders and not being ignited. The thought behind egr is at vacuum (deceleration) the valve would open and recirculate this unburned fuel back through the system, reducing emissions. The problem with this is it also recirculates all of the other crap in the exhaust (this is why if you look at the inside of the valve or the TB arount the valve, it is nasty).

Deleting the EGR reduces the amount crap that flows through your engine, but it also decreases (ever so slightly) your gas mileage. If it runs better disconnected, I would leave it disconnected...mine is .

 

thanks for the info. I unpluged it and i am getting 21 miles to the gallon with it unpluged. No complaints here on that one.