tdcarter72

Ok, I checked the vacuum from the EGR regulaor to the EGR valve and it does have a vacuum at idle.

I might have misunderstood what you wanted me to do with the battery cables, but heres what I did. I took off both neg- & pos+ cables, waited about 10 min, touch the pos+ cable to the neg- post and then attached it back to the battery, then put the neg- cable back on. I am not sure if thats what you were talking about or did I need to leave the neg- cable on the battery when doing the above?

Took it for a drive and it ran great, don't know if the cooler weather has anything to do woth it or not, but it still has a very small skip.

Pulled the codes as soon as I got back and here are the results:

KOEO - 11

C/M - 29, 33

KOER - 12, 13, 44

The only thing that has changed is instead of a o2 sensor (code 41), I now have a code 44 (thermactor air system fault).

Maybe the EGR regulator is stuck open or bad and that is allowing the vacuum to the EGR valve?

ymeski56

I think I mentioned, there should be no vac from the EGR regulator to the EGR valve at idle.

tdcarter72

You did, thats why I posted that it had vacuum at idle.

ymeski56

EGR regulator!

tdcarter72

Thats what it seems.

I wonder if the EGR would still have vacuum it I unpluged the regulator?

Would I be better off buying a new one or pulling one from a boneyard?

ymeski56

That's where it gets it's vac to function! It allows or disallows the engine recirculation flow based on the vac to it, or not to it.

Up to you. $5. at the boneyard. Depends on how tight your money situation is.

tdcarter72

Well, I unpluged the regulator just to see if vacuum would still be on the EGR valve, and yes it still had vacuum. That leads me to think the regulator is stuck open.

I ordered a regulator and I should have it in a couple of days. I will update if it takes care of the code problems or not.

tdcarter72

Well, I installed a new EGR regulator on Monday and that did not fix the problem. I still had vac on the EGR at idle. Took it back to the auto parts store and got another one, still no change in proformance, and yes there was still vac on the EGR at idle. Put a vac pump on the regulator and it had less then 1 in-HG. My manual says that the vacuum control valve will have slight internal leakage, and therefore a small amount of residual vacuum is acceptable.

Replaced the EGR valve today thinking it might be stuck open, and that did not seem to help much either during the test drive.

I have my battery disconnected to try and clear the C/M and will drive it to work tomorrow and pull codes when I get home.

I am at my ends with this truck.

walter34payton2002

Wow I just got through this nightmare. I got rid of code 33 and still have 44. I believe it is the solenoids and I will change them and report back. The 33 code.....You did what I did and replaced the egr valve and solenoid, but did you check the evp gasket? Did your egr valve come with a new gasket? Also, verify that your evp is good. As far as the code 12 and 13, correct me if I am wrong someone, but I thought those were failures to reach upper and lower rpm test limits during the KOER test. In other words, if you are idling too high you will get code 13 and if you don't get to WOT when the test instructs you to do so, you will fail to reach the upper limit.

I am interested in this as I have the dreaded code 44 and just fixed 33. The two are not related.

tdcarter72

Yes, the new EGR came with a new EVP gasket and I did use it. I am not sure if the code 33 is gone yet as I will pull codes tomorrow afternoon. I just want to get these codes out of the way so I can move forward on the rest of the truck.