So yea,
I was driving down the road the other night coming back home from my beer run 3 mins after I turned 21, and my check engine light decided to come on and wish me happy birthday .... So the next day, I took it to our local parts store and I hooked it up on a computer.... The computer said "EGR Flow Excessive".... One of the guys that work there told me to pull the vacuum hose off of my EGR valve and see if I'm getting vacuum to it.... I did that, and I WAS getting vacuum.... He told me that my EGR Solenoid was bad and the EGR valve isn't suppose to get vacuum to it ALL the time (i'm not sure if thats what he said or not though).... But I'm positive that he said I had a EGR Solenoid bad.... I went ahead and erased the code so my check engine light would go off (and it hasn't come back on).... My question is, how do I check the EGR system? And is it frequent for them to start acting up at 99,000 miles??

 

The info you were told about vacuum to the EGR is correct if that was at idle. Most likely it is the cause of the CEL also. EGR is supposed to operate at off idle speeds, at idle it will cause stalling. To verify if EGR is functioning at all, put engine vacuum to the valve, at idle the engine will quit. If it doesn't most likely there is an obstruction in the system. This might seem contrary to the code of excessive EGR, we have to remember the EGR valve as it opens, it pushes on the sensor attached to the valve. This is the EVP sensor and tells the PCM what position the valve is in, open, closed or in between. The engine has to quit with valve open and engine is at idle to be sure there is any flow of the EGR system. Hope this makes sence to you.

 

so i got another f150 for parts but its a 93 the EGR solenoid was the same as what was on my truck, so i changed them out and erased my check engine light.... the check engine light came back on shortly after that, and it said the same thing, "EGR Flow Excessive".... so you know what? i got pissed and pulled the vacuum hose off of the EGR Valve and stuck a screw in it to plug it up.... now my truck isn't running as rich on gas and it runs ALOT better.... i use to get 170 miles to a tank of gas.... i filled the truck up and i now have 130 miles on my trip meter and i still have 1/2 tank left sooooo i was reading up on what would happen if i disconnected the EGR (just like i did) and it said that it would make the truck SUCK MORE gas and it would run poorly.... now my question is, why is my truck getting BETTER gas mileage and why is it running alot better.... the only thing different is, it threw another check engine code but it said "EGR Flow Insufficient"........ hmmm i wonder why it said that i know i would fail an emmisions test, but here in West Virginia, we don't believe in those lol

 

Know what you mean, I haven't been educated enough on the subject of putting previously burned exhaust back into the intake to reburn will affect mileage one way or the other. As they say, go figure. You might try to soak the EGR shaft or pintle to free it up. Yours is sticking and acting very erratic.

 

thanks for the reply.... so your pretty much saying that i need to replace my EGR valve? and if i do replace it and get it everything working properly, will i still have the same good gas mileage that im getting now? and one more question, with me running my EGR system as it is now (vacuum hose disconnected from EGR valve), will that mess my truck up in any way?

 

if it does better on gas let it go...

EGR is just exhaust gas recirculation...it does basically 2 things...lowers combustion temps a good amount and reduces NOx gases...

The valve should have NO vacuum at idle and low vacuum and part throttle...

the valve may need to be cleaned..but there should be no vacuum at the EGR valve at idle...

 

not to thread jack but my egr valve is clicking like 3 times or so when I give it light throttle, no noise if i rev it hard, but when ever I let go of the throttle I get like a weird whistling noise, almost sounds like a bad bearing whine, but it is not. Any ideas, but once again sorry for thread jacking