EGR
Thread Starter
|
Posting Guru
Joined: Jun 2004
Posts: 1,092
Likes: 2
From: Casa Grande
EGR
The EGR valve is bad on my 85 F150, I think, because it will not hold vacuum when I test it. So I was thinking about blocking it off, vacuum port and base, for now till I can get a new one. My question is, will it being bad like it is affect my mileage? I plan on replacing it but will have to order one, no one in town carries the one for my truck.
Fleet Mechanic
Joined: Jul 2011
Posts: 1,916
Likes: 4
Some people say it's bad for gas mileage while I heard others say it doesn't hurt it at all.
The EGR itself is a valve that draws exhaust into the intake manifold so that it can take up space in the cylinders of the motor. This physically reduces the volume of the cylinder and makes the motor act "smaller" than it really is. It also makes the motor run cooler, and by making the motor act "smaller", is supposed to increase gas mileage. Exhaust gases in the combustion chambers also enable you to run a leaner fuel mixture and different timing, which really increases mileage at the expense of making a motor a turd. (think, late 70's and 1980's Chevy 350 v-8's).
Basically, I took roofing sheet metal and cut me out a solid "gasket" to go under the EGR valve that was just smaller in width to go between the bolt holes but big enough to cover up the hole going to the intake manifold so it wouldn't be able to draw in any exhaust gas. The back of my EGR valve had a nipple like a valve stem on a tire. This was on the exhaust side, so I drilled a hole open that the nipple could sit in through the sheet metal. The manifold intake side of the base plate on the sheet metal I left solid so it would "cover up" the hole to the EGR valve from the intake manifold. Make sure that you get a good seal all the way around or you'll have an exhaust leak at the base plate.My leaky EGR valve was now defeated and wouldn't stumble on acceleration anymore.
Then, just cap the EGR valve port and your done. It's completely blocked.
I think your truck being an 85 though will make it cough up and code and go into limp home mode.
The EGR itself is a valve that draws exhaust into the intake manifold so that it can take up space in the cylinders of the motor. This physically reduces the volume of the cylinder and makes the motor act "smaller" than it really is. It also makes the motor run cooler, and by making the motor act "smaller", is supposed to increase gas mileage. Exhaust gases in the combustion chambers also enable you to run a leaner fuel mixture and different timing, which really increases mileage at the expense of making a motor a turd. (think, late 70's and 1980's Chevy 350 v-8's).
Basically, I took roofing sheet metal and cut me out a solid "gasket" to go under the EGR valve that was just smaller in width to go between the bolt holes but big enough to cover up the hole going to the intake manifold so it wouldn't be able to draw in any exhaust gas. The back of my EGR valve had a nipple like a valve stem on a tire. This was on the exhaust side, so I drilled a hole open that the nipple could sit in through the sheet metal. The manifold intake side of the base plate on the sheet metal I left solid so it would "cover up" the hole to the EGR valve from the intake manifold. Make sure that you get a good seal all the way around or you'll have an exhaust leak at the base plate.My leaky EGR valve was now defeated and wouldn't stumble on acceleration anymore.
Then, just cap the EGR valve port and your done. It's completely blocked.
I think your truck being an 85 though will make it cough up and code and go into limp home mode.
Thread
Thread Starter
Forum
Replies
Last Post
porksplace
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
6
Jan 21, 2013 08:48 AM
AbandonedBronco
Ford Inline Six, 200, 250, 4.9L / 300
8
Sep 19, 2010 11:11 AM
ErrorS
Fuel Injection, Carburetion & Fuel System
4
Sep 7, 2007 10:43 PM
