Recently bought a 1990 3.1 V6 for my son and we are getting it back to running like it should.

previous owner said the CAT failed and in return it overheated the EGR which partially melted the wiring harness. Previous owner deleted the CAT and as far as I know the EGR is stuck open, the car runs rich, has a little bit of a miss and is tripping the SES light when it’s warmed up.

question, is it worth replacing the EGR seeing how there is not CAT? Would that fix my rich condition or is it advisable to remove the EGR and block it off. I live in SC and do not deal with emission testing.

I’ve done a search and haven’t seen anything that leads me in one direction or the other given my circumstance. I’m just looking for the best solution here to solve this rich condition,


Thanks.

 

If you remove it without any type of prom edit you're going to have a persistent check engine light. It won't negatively affect the way the car runs and if it's truly stuck open, will actually be a marked improvement.

 

thanks for the reply. Would removing and blocking it off fix it running rich?

I may need to research how to prom edit. I hate the light. But I hate it running pig rich even more.

 

The gasket is cheap from any parts store. Why not pull the valve and verify the pintle is stuck open before taking any other action?

 

good idea, I don’t know the first thing in how to diagnose the EGR. If I pull it off I’m pretty sure I won’t have the first clue as to what I’m looking at either. Is there a write up on here for that? I was having a hard time finding info on a 3.1 v6 EGR during my search.

 

I'm not sure if there's a write up, but the valve itself is fairly easy to see if it's stuck open. Unbolt it from the flange, flip it over, and there's a round pintle in the center. The pintle is spring loaded, and should be flush with the body of the valve. Push the pintle down and make sure it returns to its seat. You can spray carb spray on the pintle and see if it leaks inside. Sometimes you get lucky and the pintle has a giant piece of carbon holding it open when you flip it.

 

awesome thanks. So I should want it closed then and not open? Just making sure

 

Correct. It's default position is closed, and should only open when voltage is applied to the solenoids.

 

you are the man! I appreciate your help.

 

An EGR valve stuck open would cause an excessively lean mixture, if your truly running "pig rich", an always open EGR ain't to blame.....

I would, in this order;

Repair all fried wiring

Determine what codes are being generated when the SES is on, and rectify them.

Check the fuel pressure regulator, and for an injector or two stuck open.

https://www.quora.com/What-happens-i...0cutting%20off.

 

I just checked the codes and I’m getting 44 and 45 which if I’m not mistaken is a O2 lean and O2 rich. I changed my O2 sensor out yesterday so it’s new. Could this be EGR or MAF related?

 

What youre smelling is probably the result of the CAT missing... these cars stink to high heaven without them,....

I bought my car with apparently a gutted CAT nd it stank for years till i got a new one on... now I dont smell like exhaust gasses / I can breathe when the car is running.