1986 gmc C2500 smog control deletion.

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wheelchair04

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roy
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1985
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c1500
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305
I just removed the smog control off my c2500 now I have a check engine light on and can't find the aldl to check the codes. where do I need to look? It also is idling high and hesitant to go when first start out but runs fine when under power since smog control system was removed.
 

RustyPile

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1983 GMC
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1500
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350 SBC
You can't just remove smog items and expect everything to be OK.. The reason you have a check engine light is because the computer isn't receiving feedback signals from whatever you removed.. The ALDL is located at the bottom of the dash near the steering column..
 

fast 99

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Huge mistake, hope the parts have been saved, they will need to go back on. When parts are removed that are controlled by the ECM or provide data, the ECM reverts to an internal algorithm. Engine will be rich, have poor performance and drivability issues. Exactly what is occurring.

May I ask what propelled you to make this decision?
 

RustyPile

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Huge mistake, hope the parts have been saved, they will need to go back on. When parts are removed that are controlled by the ECM or provide data, the ECM reverts to an internal algorithm. Engine will be rich, have poor performance and drivability issues. Exactly what is occurring.

May I ask what propelled you to make this decision?
We'll probably never know.. The OP posted the same question on the introduction forum the same day he posted here.. Hasn't been back since, probably wasn't satisfied or happy with our responses.
 

fast 99

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We'll probably never know.. The OP posted the same question on the introduction forum the same day he posted here.. Hasn't been back since, probably wasn't satisfied or happy with our responses.
Sometimes people don't appreciate the answers. They will find out we were right after wasting time and money but probably never admit it.

There was another post on the same subject today. Wasn't in the mood to explain it again when it would have been an easy search.
 

RustyPile

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Posts
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Location
Elkhart, TX
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Nick
Truck Year
1983 GMC
Truck Model
1500
Engine Size
350 SBC
Sometimes people don't appreciate the answers. They will find out we were right after wasting time and money but probably never admit it.

There was another post on the same subject today. Wasn't in the mood to explain it again when it would have been an easy search.
Yep, I saw that one too...
 

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