94 TBI Issues

[Jeenyus_eh]

So I borrowed my truck out to a buddy and I get it back and it runs like crap. No good deed goes unpunished I guess. So here is what I've got going on... Code scan reveals code 43 & 45. Truck runs pretty decent at wot, but occasionally backfires out the throttle body, or just misfires. Idle is super low (about 200 RPM) and shakes the snot out of the truck at a stop light. Smells a little rich to me. Just replaced cap and rotor (they were definitely bad) and did spark plugs (they looked super black). No change. I don't seem to have any vacuum leaks, at least none I can find by spreading around with the starter fluid. Anybody have any suggestions? Thanks

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[Blackwater]

Have you checked the timing?

 

[Blackwater]

but change the O2 sensor first then check timing.

 

[Jeenyus_eh]

I'll be checking the timing tomorrow hopefully.

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[Jeenyus_eh]

Also have replaced the tps and iac. Forgot to mention that.

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[sntrym]

Check your Coolant Temp Sensor as well. Info on how to check here: http://67-72chevytrucks.com/vboard/showthread.php?t=425788

 

[Jeenyus_eh]

Check your Coolant Temp Sensor as well. Info on how to check here: http://67-72chevytrucks.com/vboard/showthread.php?t=425788

Good tip. Thanks. I did a new thermostat a couple months ago and the coolant was the nastiest Rusty color I have ever seen. Gave it a good flush but didn't think about the sensor.

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[Jeenyus_eh]

Pulled the coolant temp sensor today. It was surprisingly clean considering the nasty coolant it had been living in. Anybody have the procedure for checking the sensor?

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[Jeenyus_eh]

Check your Coolant Temp Sensor as well. Info on how to check here: http://67-72chevytrucks.com/vboard/showthread.php?t=425788

NVM just reread your post

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[Jeenyus_eh]

Checked the resistance across the terminals and came up with 2k ohms. Sprayed sensor tip with electronics contact cleaner until it was nice and cold. Checked ohms, still 2k. I think I'm on to something.

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