Is it the solenoid or the EGR itself

[gmhowe]

about every 5-6 weeks engine lite comes on, codes says its either the EGR solenoid or the EGR itself. So how do you figure out which it is or do I just replace both and be done with it
96 CE LT1
Thanx
Gordon

 

[Hib Halverson]

Obtain the Factory Service manual. Look-up the codes you get in the book. Follow the diagnostic and repair instructions for each code. Typically, if multiple codes are present, you begin with the highest numbers first.

 

[gmhowe]

Hib,
thanx for the response, I have the FSM but don't have some of the tools they say to use to try and diagnose it it is the P0400 code I have the OBD scanner. I don't have a vacuum guage for some of the tests they ask for. If I clear the codes everything is fine for about another 5-6 weeks then out of nowhere it comes on again. I'll try the tests they say to try all the wey op to the vacuum guage part and see what I get
Gordon

 

[vette079]

Could be a vacuum leak somewhere wich is easily checked by holding a steady 2K rpm and spraying WATER "mist" arround all the vacuum lines and intake gaskets, pretty much everywhere you could expect a vacuum leak.

You will get a change in rpms if there is a leak somewhere.

Some say use brake cleaner, wich gives a better reaction, but can get you in trouble since it´s flamable.

Check the vac. lines for breaks and in my ´91 manual it says that some vac. lines can actually sit to tight (think it was on the solenoid) so the airways get blocked.