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My Dixie Wrecked
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5,510 Posts
Discussion Starter #1
Took my truck to the shop to get the head gaskets replaced. IT was fine except for the coolant leak when I took it there.

Picked it up yesterday and now the serivice engine soon light is on and stays on. It idles fine, starts fine, and runs fine except for one thing. I've noticed that if I'm riding around town and let off to brake or just to decelerate it feels as if it slams out and into gear real quick, or like the engine has a BAD miss in it. It really random and only seems to do it at speeds greater than 60 mph. What would be causing this? The dork mechanic seems to think the light is on because he broke my cruise control cable. I called B/S for that. Any sugguestions? Like I said, it was fine before he started working on it.
 

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Mayhem, Like Me
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3,087 Posts
more info on the truck... year, motor, trans... etc
 

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Registered
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446 Posts
I bet it is the distributor. You have a 96'-98' right? With these distributors the timing is computer controlled and moving the distributor around really has no effect other than to fuck shit up. For the computer to accurately be able to control the timing the distributor needs to be rotated to precisely the correct spot. This is called CMP Retard (crank mean position?) and it needs to be within +2 to -2 degrees. The guys that worked on the truck probably just tried to throw the distributor back in and got it on the right gear but tried to time it with a light. You can't do this with 96'-98' vortecs. Its all computer controlled.

What your going to want to do it find someone with a diagnostic scanner to pull the codes that your setting. I think the code for improperly set timing of the distributor is 1345. Hopefully the scanner that you use will be able to tell you what the cmp is so you can correct it.

Heres some helpful info on the subject.
http://www.pacificp.com/forum/viewtopic.php?t=4753&postdays=0&postorder=asc&highlight=cmp+retard&start=0
 

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My Dixie Wrecked
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5,510 Posts
Discussion Starter #5
It is a 98 Z71 with the 5.7. 4l60e, basically a stock Z71

He told me that he scanned for codes, but his computer wasn't capable of adjusting timing and he did it the best he could with a light.

I just drove it to the house and back and it seemed almost like the engine dies and comes back on in a split second. I could be wrong, but thats just what it sounds like. It feels like the tranny, but sounds like the engine.
 

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My Dixie Wrecked
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5,510 Posts
Discussion Starter #6
Newest update.

Just got off the phone. They took it to the local dealership and let the GM mechanics hook it up to their computer. It said the camshaft sensor was throwing a code, so they replaced it. Now he says all the codes are clear, and it runs fine except the light won't go off. HE mentioned that the GM ppl told him there could be a short in the system making the light stay on. Is this correct? I don't care if it stays on forever. I'm about to put LED's in the cluster anyhow and take out the DRL bulb. I'll just take out the bulb for the ses light also.
 

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Registered
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807 Posts
fix the problem:imo. if you rip the ses indicator light out how would you know if you had a check engine light or not anymore?!?
 

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My Dixie Wrecked
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5,510 Posts
Discussion Starter #8
I won't. I guess I'll just leave it alone.

Wtf would make it stay on if all the codes have been checked, and the parts replaced that threw the code, then the codes are gone and the damn light is still on?
 

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Resident Guinea Wop
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14,542 Posts
The dealership is full of shit, the truck needs a relearn! Ask them to show you that there are no stored or pending codes then. You better get it fixed, because Georgia is the next state on the list for OBDII compliant vehicles - and State Inspections.

Meaning - If your MIL is on, you don't get a sticker. And there's no way for backwoods mechanics to "hook you up" with a sticker...

All vehicles 96+ w/OBDII need to be plugged into the inspection computer before a sticker can be issued. All inspection stations in the state will have to purchase a computer from the DMV in order to maintain their license.

:(

GF works for SGS Testcom, a firm that develops this new inspection technology and they just got an RFP from the great state of Georgia.
 

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Are you really sure the tech guys cleared out the codes after they fixed the problem? I'm pretty sure that a code will stay regaurdless if the problem is fixed or not until you manually go in with like a tech II or snap-on box or something and clear the code.
 

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My Dixie Wrecked
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5,510 Posts
Discussion Starter #11
I'm taking it to my fire chief, who is also a certified mechanic and has been working on shit for almost 30 years. He said he'd hook it up to the comp, check it out, and tell me exactly what was going on. I told him what the other guy said and he told me that their full o shit!

The excuse they gave me was that the camshaft sensor (never heard of that) had a hairline crack in it, so they replaced the distributor??? I dunno...

Now the temp gauge is all fubar'd. Goes from cold to 260, back to operating temp, back to 260, back to about 210..etc. kinda werid. I hope the thermostat is sticking.
 

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My Dixie Wrecked
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5,510 Posts
Discussion Starter #12
The dealership is full of shit, the truck needs a relearn! Ask them to show you that there are no stored or pending codes then. You better get it fixed, because Georgia is the next state on the list for OBDII compliant vehicles - and State Inspections.

Meaning - If your MIL is on, you don't get a sticker. And there's no way for backwoods mechanics to "hook you up" with a sticker...

All vehicles 96+ w/OBDII need to be plugged into the inspection computer before a sticker can be issued. All inspection stations in the state will have to purchase a computer from the DMV in order to maintain their license.

:(

GF works for SGS Testcom, a firm that develops this new inspection technology and they just got an RFP from the great state of Georgia.
That is just shit. Freaking Great! They have emisson testing and other stuff up in north Ga close to ATL, but not down here. Half the ppl that drive down ehre have POS's that smoke and shit like crazy.
 
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