Questions and Answers
Prelude EGR
Q. Hi Vince. I have an 1986 Prelude SI, fuel injection, 2.0. I've had a few entries in the forum. Thought I'd give you a respectable letter. My PGFI light goes on and the ECU blinks twelve, signifying EGR. The idle is rough, acceleration is rough, and stumbles. I think the EGR is stuck open.
Now, I located what I think is the EGR, it is mounted onto the inlet manifold to the cylinder head. There's a tube/hose coming from my exhaust manifold, and going into lower part of this unit. On the top of it, there is a plastic electric circuit looking solid box (can't take it off), an electric connection, and a vacuum tube. The vacuum tube goes into the box against the firewall that contains the MAP sensor, slow idle control sensor, etc. (the box I call the translator box).
I called the dealer up, who said that sometimes they have to clean out what they called the EGR CHAMBER. They said there are 3 vacuum tubes leaving this chamber, but the guy had trouble describing the schematic he was looking at. He also said they hardly ever replace the EGR valve, it costs $170.00 for the valve and the gasket (parts only), and it looks like a real pain in the butt to get to if what I think it is, it actually is.
I was hoping you could shed some light here. I attached three pictures and I circled the suspected EGR. The pictures are taken with the air intake ducts disconnected from the throttle body. One is from far away, and the other two are up closer. The real bright thing is reflecting light. Try and describe the EGR valve and chamber for me, and let me know if there's anything else in this EGR system to worry about. I appreciate it very much!
Thanks Vince!
SteveA. Here is the location of the EGR valve and the EGR control solenoid. It looks like it matches what you have circled in your pictures.
I don't know what they mean by "EGR chamber". Perhaps they are referring to the channel in the intake. It stands to reason that it could be clogged. To test it you'll need a hand vacuum pump. Hook up the vacuum pump to the EGR valve and start the engine. Pump it up to about 6" of vacuum.
If vacuum remains steady and the engine dies, the EGR valve is working properly. If vacuum does not remain steady and the engine does not die, replace the EGR valve and re-test. If vacuum remains steady but engine does not die, remove the EGR valve; check the EGR valve and manifold for blockage, clean or replace as necessary and re-test.
Additional Information provided courtesy of ALLDATA
