New to me truck. Need help tracking a problem....

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gibsonfarmsmo

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Recently acquired a 96 k2500 eclb. 7.4 auto 4wd. Bought it with trans in limp mode. Have 2nd and reverse. Also speedometer, tach, and gear indicator lights not working.

I have replaced. Trans input and output speed sensor, as well as a new distributor. The codes I was getting indicated these were the problem. After I replace distributor I plug in my scan tool to set the distributor timing. The rpm and cam retard offset are jumping all over the place. Rpm from 0 to 12k, cam retard showing 1700 degrees. At first I think it is ground. I painstakingly clean up and replace the big 3 ground locations, still no change.

I have code for cam and crank correlation but the truck won't run with a bad crank sensor. I'm pulling my hair out trying to figure this out. Any help would be appreciated. Thanks
 

AuroraGirl

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Recently acquired a 96 k2500 eclb. 7.4 auto 4wd. Bought it with trans in limp mode. Have 2nd and reverse. Also speedometer, tach, and gear indicator lights not working.

I have replaced. Trans input and output speed sensor, as well as a new distributor. The codes I was getting indicated these were the problem. After I replace distributor I plug in my scan tool to set the distributor timing. The rpm and cam retard offset are jumping all over the place. Rpm from 0 to 12k, cam retard showing 1700 degrees. At first I think it is ground. I painstakingly clean up and replace the big 3 ground locations, still no change.

I have code for cam and crank correlation but the truck won't run with a bad crank sensor. I'm pulling my hair out trying to figure this out. Any help would be appreciated. Thanks
i dont see how your assertions of facts and realities are helping you here

You sound like you have an issue with parts you replaced based on assumptions rather than diagnosis. try your oe distributor
 

gibsonfarmsmo

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i dont see how your assertions of facts and realities are helping you here

You sound like you have an issue with parts you replaced based on assumptions rather than diagnosis. try your oe distributor
I replace the distributor because I had code relating to the cam location sensor. Since the sensor is in the distributor it was more cost affective to replace the entire distributor. The oe distributor was replaced decades ago. Thia truck is 27 years old. The distributor that I replaced was a parts store replacement. The cap and rotor were worn and coroded and it was due to be replaced anyway.
 

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I almost want to say it could be something to fo with the coil or icm, seeing how the rpms are crazy. Idk if they work similarly to the tbi ones though.....just a thought
 

gibsonfarmsmo

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Sorry, I should clarify. The motor itself is idling smooth. My scan tool is reading engine rpm all over the place. 0-12k rpm, cam retard at impossible degrees. Mot sure if the readings are related to the trans.ission being in limp mode. I just know I've never seen anything like this and am stumped.
 

Schurkey

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WHAT SCAN TOOL?
Wild Guess: This is as much a scan tool problem as it is an engine/computer problem.

WHAT CODES do you have? If you clear the codes, what comes back?

Have you verified all the sensors using the data stream?
 

gibsonfarmsmo

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WHAT SCAN TOOL?
Wild Guess: This is as much a scan tool problem as it is an engine/computer problem.

WHAT CODES do you have? If you clear the codes, what comes back?

Have you verified all the sensors using the data stream?
I'm using a bosch scan tool. It works fine. Tested it on another vehicle. Codes are cam crank correlation, common error code for distributor not within 2 degrees of zero. Transmission is still in limp mode and still no speedo, tach, or gear shift indicator lighta
 

AuroraGirl

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I'm using a bosch scan tool. It works fine. Tested it on another vehicle. Codes are cam crank correlation, common error code for distributor not within 2 degrees of zero. Transmission is still in limp mode and still no speedo, tach, or gear shift indicator lighta
so... you need to do the calibration? All im seeing here is you have eithr a defective new distributor or you didnt do the full job to replace it. I dont see what is confusing second half of this pdf : https://f01.justanswer.com/kwiggins29059/1d865dc9-4e2e-4fe6-b5ac-9c44f0cbd729_dizzy+install.pdf
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heres some more

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gibsonfarmsmo

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so... you need to do the calibration? All im seeing here is you have eithr a defective new distributor or you didnt do the full job to replace it. I dont see what is confusing second half of this pdf : https://f01.justanswer.com/kwiggins29059/1d865dc9-4e2e-4fe6-b5ac-9c44f0cbd729_dizzy+install.pdf
You must be registered for see images attach

heres some more

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You must not be understanding what I'm saying and making nothing but snarky comments towards me as if I'm a hack and don't know I'm doing. My scan tool reads the cam retard offset at 1700 degrees, and reads the engine rpm at 12000 rpm at idle. It is impossible for me to set cam retard offset between -2 and 2 degrees if I can't get an accurate reading.
 
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