85 GMC C1500- EGR valve question

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85c10owner

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My truck has a code 54 and we figured out the EGR solenoid was sticking causing a misfire until it warmed up. since I have been driving it daily the misfire has gone away but it always runs a little rough. I removed the EGR valve and installed a block off plate and it runs much better and smoother. Almost cant tell its idling sometimes. I still need to smog this thing to get everything completed with the registration so I`m wondering if I put a new EGR valve on there if you guys think it might clear out my code. I know I`ll have to disconnect the battery. I really dont want to have to pay big money to get it "smogged". I`ve never really messed with anything with all of this smog crap so it`s new to me even though I`ve been working on cars, trucks and bikes for about 27yrs. All my stuff have either been pre smog or too new to worry about it. Stuck with this as a daily driver and need to get it legal.
 

Georgeb

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Did you check to be sure there is no vacuum there at idle? If you pull the line an plug it does it run better? If so your egr may be good and somthing else is wrong. If there is no change replace the egr.
 

85c10owner

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Well I already removed the egr valve and installed a block off plate and it runs much better.
 

Georgeb

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Well I already removed the egr valve and installed a block off plate and it runs much better.

Right but that may not have isolated the problem. If the egr installed but without vacuum attached runs better to then it may be an issue up stream in the control system. If you are reasonablysure the egr is stuck or leaking then try a new one. If your not sure more troubleshooting is needed.
 

skysurfer

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Why did you block off the egr when you knew you still had to get a smog check?

From what I've seen, your truck will only get a visual inspection and a tailpipe sample will be taken on a dyno. The station I go to doesn't do a physical operation check of the egr, they just verify it's there, so theoretically even a non-functioning egr could pass if the emissions were clean. This wouldn't fly with obd2, which would tell the tech the egr isn't working, but there's no such communication link with obd1.

If it were my truck, I'd slap a new egr on there, clear the cel if it's lit, and get it tested to see where you're at. Maybe it will pass, maybe it won't. If it doesn't, it's Cali law that the seller of the vehicle is responsible for getting a vehicle through the test.
 

85c10owner

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Why did you block off the egr when you knew you still had to get a smog check?

From what I've seen, your truck will only get a visual inspection and a tailpipe sample will be taken on a dyno. The station I go to doesn't do a physical operation check of the egr, they just verify it's there, so theoretically even a non-functioning egr could pass if the emissions were clean. This wouldn't fly with obd2, which would tell the tech the egr isn't working, but there's no such communication link with obd1.

If it were my truck, I'd slap a new egr on there, clear the cel if it's lit, and get it tested to see where you're at. Maybe it will pass, maybe it won't. If it doesn't, it's Cali law that the seller of the vehicle is responsible for getting a vehicle through the test.

Because it`s my only vehicle and I need to drive it while I work on it and I cant stand driving a vehicle with a constant misfire.

You may be right with the inspection but that bright orange check engine light is going to fail the smog before it even starts.

I might just put a EGR on there to see if that fixes the problem. I`ve tried clearing the check engine light and it wont go out. Something is still causing a problem and I figured that since the truck run better and smoother without the EGR valve that maybe the one I had was bad.

Its always been the sellers responsibility to smog the vehicle for resale unless it`s listed on the bill of sale, "parts only" or "As Is" which is the case of my truck. The seller said if I wanted to deal with the smog he would take a lower price and when I originally drove it home I did not notice the check engine light. I didnt notice it until after I did a tune up so I dont know if i triggered something or if I just didnt see the light since it has a smaller steering wheel than stock and my hand covers the light when I drive it.
 

Jarhead79

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Where does the egr vacuum hose run to anyway? My egr is still attached to the intake, but the hose is not connected to it.
 

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