On the 3.8 and ’98 Z38, Chevy, for some reason used a Linear EGR.

My question is, how do I test the EGR valve?

What I’d like to do is take it off and connected 12V to one of the five connectors but I’m not sure which on to apply it to. Which one actuates the valve and what Voltage does it work at?

From tests I performed today, there seems to be:

• Two 13V lines in that are always hot (IGN on)
• Black Ground
• 5V (IGN on)
• .82V (IGN on) (Chilton says it is a Valve position sensor or something?).

Simply put: I don’t want to fry the thing so I’m asking you guys hoping that somebody has done this before.

Also, I seemed to set the engine service light while checking the valve and it wont go off even after disconnecting the batt for 30+ seconds. How do I turn it off or read the code w/o a scanner? 1997 Camaro 3.8 OBDII.

 

You can't read a code in OBD-II without a scanner, but they are available for as little as $40. If the light stays on, the "code" is still active.

 

How do I clear the code? I disconnected the batt for 30-40 seconds, should that do it?

 

You can clear most OBD-II codes by removing power to the PCM for 30 seconds.... best way to do it is to pull the "PCM BAT" fuse. But if the problem is still there, the code's going to set and the SES light is going to come on as soon as the PCM runs the diagnostic again.

 

Well, the code is off today. 'Don't know why...

Anyone have an idea about the EGR?

 

Is there a more technical-based forum for Chevrolet vehicles?

 

Might want to try the "V6 Tech" forum, since that's where you'll find the people who know the specifics of the linear EGR valve. Most people have V8's and they use the PWM EGR, which is completely different.

 

I've seen some Blazers w/ EGR problems at the dealership I used to work at. It would come in sumbling and running like crap.

I learned after a while that it was actually a piece of carbon holding the pintle open. Thus causing a vaccuum leak.

Is the car running normal? If not try cleaning the EGR valve. Remove it and use some carb cleaner on it and a wire brush.

 

You've been helpful, thank you. 'Guess I'll make threads in multiple sections next time I have a tech question.

The 1998 Z28 had a linear EGR actuator that is why I posted here.