Pre ‘93 4L80E

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Amsterdamned96

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I was handed down a truck with a plethora of electrical gremlins. I’m currently redoing the wiring harness which was damaged in a fire. I’ve read that prior to 95 the 4L80E didn’t have a crank position sensor? I also can’t find one (engine has been pulled by me) is it perhaps integrated into the started somehow? Most importantly I’m trying to find out what the vertically mounted computer between the brake oil reservoir and relays on the driver side is. In addition to this I’m also asking myself what this aluminium box is?

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stutaeng

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The crankshaft position sensor started with the '96+ "Vortec" engines. 4.3, 5.0, 5.7 and 7.4.

The 4L80s from inception (91-95) were mated with TBI engines and did not not have a CPS, so that's correct; but that's specific to the engine, not the tranmission.

unfortunately, I know very little on those trucks, but you may be seeing the ECU? Highly recommend a wiring diagram to figure stuff out.

Someone with more knowledge about these trucks please chime in.
 

TagAllen

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Although I have not seen a box exactly like that going by the wires and plug I would guess it is a esc which is short for electronic spark control. I believe it controls the advance/retard of ignition timing.
 

d0GrEd94K1500

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Truck starts and stalls, which is up from the misfires. No scannef, no pressure tester. Grindiing this out on a 15 yr old Wyotech degree, an amount of tools just enough to make me useful, or dangerous. Uncle Sam trained me not to fail. I have the completed image of this heifer burned into alligator brain and I refuse to lose. Yet here I am, cover in hand, doingbth hardest thing; asking for help, before it accidently rolls off a cliff just pulled an 82 code (crankshaft position sensor error) off my 94 k1500 tbi, yet everwhere I've inquired, says that the '94 does not possess the crankshaft position sensor. I also pulled 34 (MAP sensor circ. error - hi vac) and 43 (Knock sensor error). Oh, and there is a parasitic draw somewhere, because the battery is shot after a few days non-op. Runs rich. timing sits between 6.80 and 7.60, then will go 0.00. Six months now.
 

someotherguy

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Truck starts and stalls, which is up from the misfires. No scannef, no pressure tester. Grindiing this out on a 15 yr old Wyotech degree, an amount of tools just enough to make me useful, or dangerous. Uncle Sam trained me not to fail. I have the completed image of this heifer burned into alligator brain and I refuse to lose. Yet here I am, cover in hand, doingbth hardest thing; asking for help, before it accidently rolls off a cliff just pulled an 82 code (crankshaft position sensor error) off my 94 k1500 tbi, yet everwhere I've inquired, says that the '94 does not possess the crankshaft position sensor. I also pulled 34 (MAP sensor circ. error - hi vac) and 43 (Knock sensor error). Oh, and there is a parasitic draw somewhere, because the battery is shot after a few days non-op. Runs rich. timing sits between 6.80 and 7.60, then will go 0.00. Six months now.
Welcome,

You should start your own post as you have a different vehicle and symptoms from the 4 year old post that you tagged onto. No harm done but it will be clearer for anyone responding which vehicle specs and set of symptoms they are considering.

Also you'll find in the Engine section, sticky'd at the top of the list of posts, free downloadable scans of the factory service manuals. Get the one for your 1994 model and look up your code #'s there. I don't have my '94 manuals in front of me but you will find in there the specific definition for a code 82 (and the others) for *your* vehicle and a troubleshooting path for it.

Richard
 
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