Hailing a chevy mechanic

[cpj]

I have an 87 chevy suburban, it is showing an EGR valve trouble code.(it comes and goes) My question is this: is there a chance that I could get away with cleaning the carbon and gunk out of it rather than replacing it?. It has a 350 with TBI, 2wheel drive, air conditioning, 1/2 ton model with 143000 miles on it.<br />Thanks in advance for your help.

 

[Kenneth Brown]

Re: Hailing a chevy mechanic

Absolutely. Its gonna be nasty and hard to get out but its do-able. I use small drill bits to get it started and then chip away. I soak it in Berrymans B12 spray also. The Berrymans works better than the wallyworld for this application.

 

[cpj]

Re: Hailing a chevy mechanic

I hear ya on the berrymans KB. I love that stuff and thats all I use now. It is rather uncomfortable if you get it in your eye, however. I plan on trying to clean it tommorrow.

 

[bubbakat]

Re: Hailing a chevy mechanic

cpj sea foam will clean it to and pb blaster will.<br /><br />The mech. That works onmour patrol cars clean them with sea foam to.<br />All it is carbon build up

 

[cpj]

Re: Hailing a chevy mechanic

ARRRRRRRRRRRGGGGGGGG!!! Just tried to clean the EGR valve, and I found that it wasnt that dirty at all. Which sucks, because that would have been the easy way out, just to clean it. I attached a piece of hose to it, and checked the diaprham. It has a hole in it somewhere. Off to the auto parts store with about 80 bucks to get a new one.

 

[bubbakat]

Re: Hailing a chevy mechanic

Yep life sucks sometimes.

 

[cpj]

Re: Hailing a chevy mechanic

Replaced the EGR valve and all seems good. (so far) It was 56 bucks, left me enough for some plug wires.<br />Whats strange is that the check engine light only came on every once in a while, and it happened within a mile or two of the same spot on a certain higway, and on another street here in town. As soon as I would shut it off, the light would go out and it would be fine for awhile. It never would stay on after I shut it off. Matter of fact, I was so sure that I knew when it would come on, that I bet my buddy 5 bucks that I could tell him within two miles when it would come on. And I won. If anyone knows why it only came on at a certain spot, please let me know. BTW, it was warmed up long before I reached that spot. It was probably 25 or so miles from the boat ramp when it would happen.

 

[petryshyn]

Re: Hailing a chevy mechanic

Was it code 32?<br /><br />Under specific driving conditions, the ECM will Diagnose the EGR operation. It does this by applying vacuum to it through a vacuum switching valve. It then looks for fluctuations in O2 sensor readings. If it doesn't see any, it knows EGR is not working. Electrical connections, bad switching valve, EGR diaphram, and plugged passages all can cause this. If you have a positive back pressure valve, you will not be able to test it by simply sucking on the vacuum port. It will appear to be leaking...

 

[cpj]

Re: Hailing a chevy mechanic

Schematic,<br /> Thats sounds like a good guess. And that explains why the new valve also appeared to be leaking. Oh, well you learn something new every day . But it does seem to be running better than it was with the old valve. And what would those specific driving conditions you speak of be? And yes it was a code 32. Thanks for the help every one.

 

[imported_bjs]

Re: Hailing a chevy mechanic

i had a 88 chevy truck with same problem the engine was same set up as yours i had to take off intake manifold clean egr passage with a wire was plugged up.theres a passage for vacuum that was packed solid with gunk. that passage is small so it dont take much to get clogged.its worth a try.

 

[KRS]

Re: Hailing a chevy mechanic

Where's KeltonKrew when you need him..... I thought all chevy drivers had to be mechanics ?

 

[jimr]

Re: Hailing a chevy mechanic

Originally posted by KRS:<br /> Where's KeltonKrew when you need him..... I thought all chevy drivers had to be mechanics ?

No thats Dodge drivers