EGR stuff on C engine

[Subzilla]

Greetings,
Finally got around to pulling off the C/EGR intake to install a J intake on the '86 this past weekend. I've always read to remove all the EGR stuff but I'm just wondering about what I'm looking at on the engine. I have the vacuum tube that runs from the air cleaner to a solenoid(?), then from there to another device next to it with a electrical wire atached to it. What is this device in line with the EGR with the wire? And can I or should remove this also? Thanks and have a great Independence Day!

[john8662]

The other device is an EPR, it's basically a flapper valve in the exhaust manifold on the driver's side. I've disabled mine on all my rigs. But, if it ain't broke don't fix. The easiest thing to do (looks better) is to just leave both solenoids on the bracket on the valve cover in tact but disabling EGR on the intake side. I like to cut the egr hose short and just plug it on the output of the EGR solenoid.

Remember, you'll still have a hole in your air cleaner assembly to plug where the EGR hose entered!

[Subzilla]

Thanks John. Yea, that was my plan B as my plan A was to take off everything. I guess I wanted to make sure I'm getting the most power, of course. I also wanted to get everything I could out of the way for looks and for ease of future repair. I'm familiar with the flapper in the exhaust but still what does the electrical connection do? Does it opererate based on engine temperature?

[Diesel Blue]

Hi,

I just purchased a 1989 Suburban with a 6.2 liter engine. I had a problem with the small flapper valve located within the driver's-side exhaust manifold (EPR Valve). The valve always stayed in the closed position regardless of engine temperature; thereby restricting the exhaust flow on the driver's-side of the engine.

The wires you mention (pink and green I believe) connect to a solenoid under the air cleaner and run to a temperature sensor located at the rear of the passenger-side of the engine, under the exhaust manifold. The temperature sensor controls the solenoid, which in-turn allows or cuts-off vacuum to a diaphragm located on the side of the flapper valve. My temperature sensor apparently is bad, since if it was working correctly, the flapper valve would open as the engine warmed-up.

For now, I disconnected the wires at the solenoid, and the flapper valve now stays in the open position, regardless of engine temperatrure. I am not sure at this point whether this will have any negative effect in the winter, but my plan is to replace the temperature sensor and re-connect the wires so that everything will be the same as when my truck was new.

Hope this helps!!!

Alex