Joeyblaze

Since it's obd1, they can't connect a scantool. They use the sniffer and visually inspect it. If I shut the truck off before I take it to the e check, the engine light will turn off. However, when the test actually happens, the sniffer reads high nox. Then back at home, I can check for codes and it shows a code 32.

Didn't follow the ecm ground but I had power to the solenoid

Thanks again for all the advice. Feel free to put any new ideas up here too. I've been banging heads with a bunch of people. Always nice to hear other people's perspectives

I'll try what you guys are saying. I'll put a new thermostat in it, just really wondering if a differently calibrated egr valve would solve the problem. I need to get it fixed asap like I said but I'd really enjoy it if the check engine light didn't pop on every time I took her on the highway too. Crossing my fingers for possibly better gas mileage with less emissions too. Thanks again. I'll post if I ever figure it out

With what I just said about the laser Temps, would you still do that. Like I said, the thermostat reading on my dash is showing its not that hot at all.

No pinging. The motor runs flawlessly. Idles great. Good acceleration. I don't have the combustion temp, but I pointed a laser thermometer on the exhaust manifold(228*f), valve cover(145*), and the Catylitic converter(290) and they seemed to be in a normal range.

And ya, I read up on that post earlier. It seems to confirm everything I knew. Like I said tho, I replaced about every part in the egr system, I just can't figure out why it's still throwing a code and failing e check.

My next thought is to get a new egr valve again, particularly a Delphi or oem one, Bc the one that is in there now, while new, was only thirty bucks on rock auto. I don't want to be blindly throwing money at it, but maybe a more expensive egr valve will work. Any thoughts? Thanks again

There's no buildup inside the egr port and yes, when you suck on the line or when u just push the egr interior with your finger you can get it to stumble quite easily

I have a 1995 GMC k1500 4x4 with the 5.7L TBI engine in it. I just bought the truck and as it is about 24 years old, it only needs to pass one more emisions test before It is grandfathered and therefore immune to e-checks (I live in northern Ohio) and also before I can get plates for it. The problem is, I've failed e check 3 times. A code 32 pops up every time I test it (on my own with a reader) and when I got the emissions test, high nox is the reason it fails. This would make sense, as code 32 is an egr error, and the egr being faulty would definitely trigger high nox, however: The egr valve has been replaced (yes, a negative one) The egr vacuum solenoid has been replaced Map sensor replaced Spark plugs, cap, rotor, wires. Replaced Even went as far as to replace the oxygen sensor. There doesn't seem to be any vacuum leaks and every test I've done on any part of the egr system points to it all running correctly. The kicker is: the truck runs great! No loss in power. Idles great. Super clean and well kept truck. Notes : it does have a Flowmaster super 10 dual exhaust on it, but it isn't a true dual as only one pipe comes from the catalytic into the exhaust, Then two come out. Also, high nox seems to be caused by high engine Temps, however, my engine temp on my dash shows that it never gets above about 165 or 170*. Idk if this is relevant but it seemed strange. Any help is greatly appreciated. I'm really at a loss and I'm running out of time before I need to buy another temporary tag. Thanks again - Joe