Need Picture of EGR system

sd_iconoclast

Registered User
I have an '89 SC % speed. I failed a smog check and it is likely that the EGR valve is my problem. I can just barely see the valve itself, but I have no idea where the tube is or where it goes. I have the factory manual, but I cannot find any coverage of teh EGR system in it.
Does anybody have a picture or drawing of the whole EGR system?
I would like to see teh valve, tube, abd the vacuum hose that goes to the valve.
 
I don't have a picture handy but am very familiar with the EGR. There is a metal tube ~1/2" in diameter with a bellows on it for heat expansion that connects the bottom of the EGR valve to the exhaust manifold. The valve bolts onto the backside of the upper intake manifold just behind the throttle body with two 10 mm bolts. A silicone tube connects from just below the valve to the EGR canister. It's a small gray or black box with an electrical plug on it held in a metal clip next to the EGR valve. Also there is a vacuum line on top of the valve. The bellows tends to break and the canisters can go bad as well as the valve itself going bad. To get to it you have to remove the long rubber strip and the cowling covering the bottom of the windshield and wiper posts. It's very difficult to get to as there is not much room. Usually the EGR system will turn on the check engine light and give a 31, 32, 33, or 34 code if something goes bad. My EGR keeps turning the CEL on and off and gives a 31 or 34 code but passed emissions with flying colors.
 
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I don't think you egr is the problem for not passing emissions. unless they visually inspected it and saw something was leaking, which would be a task in itself.

Do you have teh printout that tells what specs where out of range during the test?
 
I don't think you egr is the problem for not passing emissions. unless they visually inspected it and saw something was leaking, which would be a task in itself.

Do you have teh printout that tells what specs where out of range during the test?

Here is the picture of the results.

Also, here are some details that may be important:
I drove the car straight to the smog station (5 minutes away) after not driving it for a week.
The car then sat for an hour while the technician was at lunch.
I have forged pistons. The piston slap sound is noticable for about 15 minutes after I start teh engine for the first time in the morning.
 
Here is the picture of the results.

Also, here are some details that may be important:
I drove the car straight to the smog station (5 minutes away) after not driving it for a week.
The car then sat for an hour while the technician was at lunch.
I have forged pistons. The piston slap sound is noticable for about 15 minutes after I start teh engine for the first time in the morning.

Ooops, picture did not come through. I will try again:
 

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I just tested my EGR system by doing the following:
I started the car and let it idle.
I applied vacuum to the EGR valve.
The engine started stumbling noticable, but did not stall.
I released the vacuum, and the stumble went away.
Does this mean that the EGR is OK?
Should it have stumbled so bad that it stalled?
 
Found this on the web.

The most common cause for increased NOx emissions is higher than normal combustion temperatures, this can be caused by a malfunctioning EGR system, engine overheating, compression too high because of carbon build up, misadjusted timing.

Maybe try it when the car is cooler. Or pull the eec temp switch so the fan runs constant.

Guess it could be your EGR.

I don't know much about emissions, except that I hate it!
 
correct me if im wrong here. i remove the egr valve, plug all line and pipe, install a block off plate witch i have one. then simply enjoy no stinking egr?
 
It does sound like your EGR is working. Try pulling the spout plug to pull some timing and try it again. Too much timing can cause high NO. The engine should be warmed up real good but the coolant temp should be low.
 
How old are your cats? My '93 never failed test, but I compaired sequential tests. The old test my cats were the original, and the HG's had blown while they were installed. The second test was after I had the exhaust replaced, running 2 larger cats w/o the 2 into 1 center cat. NO2 level was significantly lower (I also made sure it was well warmed) this motor has 130+Kmi and OEM non-EGR.
MikeH
 
How old are your cats? My '93 never failed test, but I compaired sequential tests. The old test my cats were the original, and the HG's had blown while they were installed. The second test was after I had the exhaust replaced, running 2 larger cats w/o the 2 into 1 center cat. NO2 level was significantly lower (I also made sure it was well warmed) this motor has 130+Kmi and OEM non-EGR.
MikeH

I forgot to mention that my cats are probably about a year old. I have not driven the car much in that time. I think they are in pretty good shape.
 
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