i have a 1992 ford f150 with an i6 engine. my smog pump is going out and i was wondering would my truck run better with the smog and egr deleted? the truck has the cat removed so the pump has no function, what all would i need to do?

 

The whole air injection system can be deleted without any adverse engine effects or activating the check engine light, but the EGR cannot.

 

If you want to fully delete the air injection system you can plug each of the six inlets with 2.5" long 9/16-18 bolts.

The EGR plumbing can be removed physically, but it needs to left in place electrically or a code will be set. There's probably some way you could fool it, but I've never read of anyone successfully doing that.

 

The only way to delete any of these systems and not have codes generated is with a chip or tuner that is programmed to turn these systems off inside the PCM, but that is a but more effort and expense than most people want to expend.

When the AIR system is deleted codes will be set but they aren't high enough priority to set the check engine light.

When the EGR system is deleted there are also codes set but they are high priority and will trigger a check engine light. There is also a plug-in device that is advertised as something that will prevent EGR codes but it only prevents 1 type of code so other codes are still set and often the check engine light still gets illuminated.

 

i understand that the engine light comes on when the codes show up, but with that being said will it have any negative effects to the performance of the engine? Its an old ford in my experiences the engine light is always on haha

 

I have blocked the EGR valve on these engines so that no exhaust gas can flow into the motor and experienced no negative effects, the volume of exhaust gas and the conditions when it is used are small and limited so while it can have a small measurable impact on cruising fuel consumption it's not really something that can be felt from the drivers seat.

 

The AIR system is all about reducing cold emissions. You'll pollute a little more, but doubtful you'd notice any change in running.

In theory removing the EGR might drop fuel mileage by a tiny bit, but probably not anything you'd notice. Some have indicated that removing it improved drive-ability in a small way.

If you have error codes now, I'd find out what they are and diagnose accordingly. They do serve a purpose and that's why it's worth having a system that isn't in "perma error code mode".

 

Agree with the above. My own experience is that a functioning EGR system is probably good for 5+% better gas mileage (higher in stop and go driving). That might not sound like much, but if you're putting 20 gallons (say $50) in the tank every week, that means a functioning EGR system is saving you at least $125 a year.

The EGR system is a very cool "trick" to make a big engine act like a small engine when you don't need power. Feeding exhaust back into your engine sounds crazy until you think it through and realize the benefits.

And even engineers (especially engineers!) will argue about this stuff. Here are two threads with smart people arguing both sides:

https://www.physicsforums.com/thread...r-loss.663150/

EGR and how it adds to fuel economy??? - Engine & fuel engineering - Eng-Tips