95 ciera,3.1 sfi stall at 180 degrees, egr question

[D Ryan]

95 old cirea
3.1 sfi
62K miles
　
　
　
I removed the egr today to check it out, would like to know what is the best way to clean out the interior of the valve? Is there somthing better than carb cleaner spray, I have a bucket of carb cleaner and could submerige the bottom part of the valve, its steel, the small cyclinder that moves up and down i’m not sure of!
I bench tested the valve and all coils move when energised. I placed a small scre driver in the ports and 2 were free, 1 would not move, I didn’t force it, but it does move when power is put to it.It is the on with the most carbon in it. 2 of the ports do not close all the way, but close to it.

[maxwedge]

Just clean the pintle do not dunk it as it is electronic, why are you doing this, problem or maintenance?

[D Ryan]

Originally Posted by maxwedge

Just clean the pintle do not dunk it as it is electronic, why are you doing this, problem or maintenance?

Problem

Took ele egr apart yesterday and cleaned it up, got some testing to do today.

The eng throws code po321 and stumbles and dies , this occures only when water temp reaches 180 to 185 degrees.

Here are some results I got from testing:

I keep getting drawn into this heat related thing where I watch the temp guage and 180-185 the eng stalls and lights the dash SES

All test were done with a cold temp eng!
first test:
everything hooked up
eng running good
temp get to 180 eng stumbles and dies, drops the cam sensor code

clear code
second test:
disconnect wiring harness plug to Digtal EGR
upon startup dash lights, computer sets p1650 code (autoxray)
eng still running good .
eng continues the run well passing 180 degrees and up to 220 degrees
fan does not come on
computer did not set cam sensor code at 180 degrees
stop test

clear code
third test:
connect wiring harness to Digital EGR
No codes set after startup, eng running good
temp rises to 180 eng stalls again and dies , computer set cam code again.

clear code
forth test:
disconnect wirning harness to Digital EGR
P1650 code sets on startup, eng running good, passes 180 degrees, at 220 degrees I pluged the EGR plug in with eng running, fan starts,eng runs good , 1hour no problems!

[D Ryan]

update:

I Ohmed the 3 coils and got 24.1,25.1, 13.8.
I did a AMP draw on the 3 coils and got :
Green wire .06
Brown wire .06
Red Wire 1.00

I think all these readings are good!

With the car operating at about 200 degrees I seen no signals from the computer to operate any of the coils.

Not sure if this is normal, any ideas?

[maxwedge]

That can be caused by a bad icm or crank sensor.

[D Ryan]

Originally Posted by maxwedge

That can be caused by a bad icm or crank sensor.

Been there done that!

Something is happening when the water temp reachs 180-185, it never rarys. If I wanted to I could start the the car with the egr harness disconnected ( this will set code p1650) wait for the car temp to reach over 200 degrees and plug harness back in with eng running. Then drive around with the MIL light lit. Eng runs good. (see the test above)

The EGR is just a place to start! So far I have seen no signals being sent to the EGR to open.

My question is when should I expect to see a signal? Anyone!

Thanks for the input

[maxwedge]

What signals do you mean? the digital egr is powered all the time and the ground is pwm as commanded by the pcm, this does not occur unless you are driving under a certain load and speed. A full scan is required to see this occur.

[D Ryan]

Originally Posted by maxwedge

What signals do you mean? the digital egr is powered all the time and the ground is pwm as commanded by the pcm, this does not occur unless you are driving under a certain load and speed. A full scan is required to see this occur.

Thanks thats what i'm looking for! Your saying that it has to be under a load!

All testing here is being done at idel, starting with a cold eng.

I thought maybe with a cold engine that some of that hot exhaust might be directed to the intake.

I would like to simulate the load condition some way without driving the car.

My scanner is not capable of doing live data at this time. It will have to be logic probed.
Any ideas! Anyone!

[maxwedge]

Under load and speed and warmed up for the pcm to ground the egr, they were troublesome in these cars and I have seen stalling conditions occur. Of course this will only happen at very low speeds or idle.