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Dead Parrot · 11-17-2017, 10:45 AM

Your test run that showed 20 inches vacuum at idle is a good number. Since all the plugs are black and wet looking, sounds like a too rich problem.

On a computer engine, could be an bad O2 sensor sending a lean signal and causing the computer to go rich to fix. Or could be a knock sensor malfunction and causing the computer to go rich or retard the timing.

There should be a sticker somewhere with the idle timing. If sticker missing, a good start point is 8 BTC. Measured with the vacuum advance disconnected and the port capped. Most stock motors like a lot of timing advance.

Cheap thing to check is the little button on the inside top of the distributor cap. If worn out, can cause all plugs to misfire.

11-17-2017, 10:45 AM	#10
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,478	Re: Can anyone help me get this truck running correctly? Your test run that showed 20 inches vacuum at idle is a good number. Since all the plugs are black and wet looking, sounds like a too rich problem. On a computer engine, could be an bad O2 sensor sending a lean signal and causing the computer to go rich to fix. Or could be a knock sensor malfunction and causing the computer to go rich or retard the timing. There should be a sticker somewhere with the idle timing. If sticker missing, a good start point is 8 BTC. Measured with the vacuum advance disconnected and the port capped. Most stock motors like a lot of timing advance. Cheap thing to check is the little button on the inside top of the distributor cap. If worn out, can cause all plugs to misfire.