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Old 02-28-2012, 04:04 PM
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Originally Posted by cobalt327
What has been changed between when it ran OK and now?
Between when the timing was done by ear last summer and when the truck first began exhibiting these problems, all I did was begin the cooling system flush, an oil change and added a can of Restore. The other stuff was the cables and battery posts. It drove just fine up until the day before the problems began.

After the truck began having problems, I was advised to check the ignition components. I check the spark plugs, the ICM and the coil. The spark plugs were fouled, more so on the passenger side (pictures in post #9). The ICM passed the test at Autozone twice. The coil was tested using a multimeter and while I was able to get a reading for the primary, but not for the secondary. The coil was swapped out under warranty, but the results were the same (post #9). Once I put everything back together, the truck began running just fine again. But there was some light smoke seen from the passenger-side of the firewall. It began a few minutes after the truck was turned off, and was there for a couple of minutes at the most.

Ever since after that, the truck only ran fin the next day. I cleaned out the glass-cased fuel filter in front of the carb which had crud in it (pictures on page 3, post #33). I checked on the choke. I tried running it with the choke plate wired open. Most recently, I moved the distributor back and forth and turned out the idle mixture screws on the carb to a full six turns (same as before). The distributor ended up in the same place as before, with the canister touching the intake manifold. I did not take for a spin after that.


This morning, I started up the truck to move it for the street sweeper. I let it warm up for a about three minutes and then began moving it to park on the other side of the street. As soon as the truck began turning, the "Oil" light came on for a brief moment. I let the truck continue to warm up for a bit and then decided to take it for a spin.

The truck ran pretty good. Not perfect, but the shifting was happening a lot more quickly and softly and there wasn't much hesitation. Definitely no bogging. But I could detect slightly less power. I took it onto the main street and it got up well beyond 45 mph before I had to slow down. I parked the truck and it revved with no hesitation, even though it had been hesitating around the 2,500 rpm mark. The "Oil" came on only once and it was soon as I began driving and made a turn.

I turned off the truck and came back to it about 30 minutes later and took it for a quick spin. As usual, the idle was a lot lower than when it is first started in the morning (1,500 rpm vs 750 rpm). Again, the truck ran good, but not perfect. I parked it again and came back to it about an hour later.

Letting the engine run and leaving the transmission in "Park", I first checked the transmission fluid. Didn't see much on the dipstick. I put it back in and checked it again:

I then turned the engine off and checked the oil. Nothing showed on the dipstick. I then started truck, let it run for about 30 seconds, turned it off and checked again. There was quite a bit of oil after that:

So that's where its at. Some time tomorrow morning, I should be posting results from hooking up the vacuum gauge to the intake manifold, along with a test of the diaphragm. Maybe even check a plug or two. Distributor re-installation tentatively set for Saturday.
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