EGR Valve Coil Resistances

[RLJ]

Greetings,
90 Lumina 3.1 390 000 KMs
Car threw a code 32 (EGR) the other day. Seems to run ok, except for a rough idle and a stumble on acceleration.
Pulled the valve, cleaned & tested it.(some carbon was sticking one of the pintles) All 3 solenoids fire properly, but I noticed that 2 of them read around 22 ohms and the other at around 12 ohms. So I compared it to a couple out at the wreckers and found the same thing. Does anyone know if this is okay, or is this one of those "common problems". Don't want to buy a new valve unless I absolutely have to, as they run up well over 300 bucks here.
Thanks for any replies.

[bszopi]

I'm assuming that it is the digital EGR. If so, here MIGHT be an explanation...

Solenoids 1 & 2 are the same size, whereas solenoid 3 is slightly larger. The larger solenoid have a larger coil, thus resulting in a difference in resistance readings. I'm not saying that its 100% true, but it is a possibility.

[RLJ]

Yes, its a digital one. Didn't notice a difference in the size of the coils. Will have a closer look.

[Homer]

The book just says each solinoid should draw between 0.4 - 1.0 amp. So E / R = I, with the car on you have around 14.3 volts, 14.3V/12Ω= 1.19A, which will set code 32.

[RLJ]

Hmmmm. That makes sense, but but as I said. I found 2 others with the same readings on the same solenoids. It seems fine for now. No codes today. Idle is better, but still a stumble on acceleration.
Anyone got one lying around they could measure?
Thanks for the replies.

[JayBear]

I have an old one where two of the solinoids are 22.6 and the other one is 12.2. It has 100k on it, and when i replaced it that last solonoid was drawing just over 1 amp and now the new one is only drawing .80 amps(resistance is greater). I will check out a brand new one when I work tommorow to see what the resistances are on that.

[Homer]

I just took an old one apart and I found out why it failed me, one of the springs got messed up and the valve wouldnt retract causing it to stay open and always send exhaust gasses into the intake. There was carbon on both sides of the valve so I could tell its been open for a long time. I just twisted the spring and it went back into its seat and now its as good as new(except the rust and corrosion).

[julu 94 zrs]

Final result...?

so when throwed a code 32, just take it off and clean it? i got a 3.1 giving me that code... ?

thank for the help

[Homer]

Final result...?

so when throwed a code 32, just take it off and clean it? i got a 3.1 giving me that code... ?

thank for the help

Its to cold to go outside and try it, plus I got a good working one on the car that I dont want to mess with since it is working at the moment. This isn't the first GM digital egr that all I had to do was rebuild it to fix it. A lot of the problems with these are the solniods shorting out becasue of excessive heat. Having a messed up spring though wont throw a code 32 but it could casue the egr no flow code, I think its code 54 or something like that. To take this egr apart all you do is take off the 3 torx screws with a T-20 bit.

[RLJ]

I have an old one where two of the solinoids are 22.6 and the other one is 12.2. It has 100k on it, and when i replaced it that last solonoid was drawing just over 1 amp and now the new one is only drawing .80 amps(resistance is greater). I will check out a brand new one when I work tommorow to see what the resistances are on that.

Muchly appreciated!

[Homer]

I checked out a new one and the resistances are 22Ω, 22Ω, and 12Ω ohms. I guess the service manual is wrong on the exact values. Usually when I get codes I just record them then delete them and see if they ever come back, and if they dont come back I just forget that it ever happened.

[RLJ]

Excellent!!!
That means I'm good to go. The sticky pintle was the culprit. I thought so as its been fine since I cleaned it.
Thanks!