White Smoke When I Let Off

Black dawg

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Ok got it to work, it’s at 10.4 at 2000 RPM. I was hoping it would be further off.

Next I figured I’d check each injector line to see if there’s any effect on idle. Not sure what else to check.

I was also going to check the fuel supply pressure to see if the lift pump was working. It didn’t register anything on my gauge; I figured I’d pull the hose and crank it to see if anything comes out.
Did you happen to notice timing at idle?
 

bilbo

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I should have written it down. I still have the probes on the engine and I’ll check it when I start it up again. I’d like to see if it changes at all with the new fuel filter.
 

Isaac Ristow

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I had a very similar issue couldn't figure it out I was messing with timing and all kinds of stuff and over looked my fuel filter since it was pretty new well I cleaned my rear tank out and made it work residual sediment clogged my fuel filter after acceleration and letting off it would miss buck and smoke grey heavy acceleration I had lots of grey smoke and higher EGTs every time I checked the timing it was dead on well at 2000rpm no load it will be not requiring much fuel, EGTs were also high like yours. I spun a new filter on eventually and it was all good chased a rabbit tail for a plugged filter... Its easy to over look that stuff. If its not the filter I would still check fuel pressure ideally under load because low pressure/starvation of fuel feed dramatically changes timing it retards it more pressure increases timing maybe your lift pump is on its last legs or you picked some **** up at the station and partially plugged a line or fuel pickup. I also had the advance stick full advance in a injection pump once thing sounded like diamonds in a blender limped it home maybe they can stick full retard too. also check your advance cam/leaver on the side of the pump too.
 

bilbo

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I drove the truck yesterday and it behaved normally. I can’t explain why, but it appears the fuel filter may have been causing the issue. Or something gummed up in the fuel system that the cleaner helped work it’s way through.

I checked timing again this morning with the new filter and it’s 12.5 at idle and 9.9 at 2000 rpm. While checking, I found something else that was concerning. The upper radiator hose was stiff just after starting, which makes me think combustion gases are getting in there. I hope there’s no cavitation. I went to test the coolant and I think my test strips have expired. The DCA spot is very dark on all of them.
 

Isaac Ristow

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I drove the truck yesterday and it behaved normally. I can’t explain why, but it appears the fuel filter may have been causing the issue. Or something gummed up in the fuel system that the cleaner helped work it’s way through.

I checked timing again this morning with the new filter and it’s 12.5 at idle and 9.9 at 2000 rpm. While checking, I found something else that was concerning. The upper radiator hose was stiff just after starting, which makes me think combustion gases are getting in there. I hope there’s no cavitation. I went to test the coolant and I think my test strips have expired. The DCA spot is very dark on all of them.
Two ways I check for compression in a radiator is with the engine cold take the rad cap off to relieve any residual pressure put it back on and start the engine DOT NOT rev engine at all let it idle (revving the engine the water pump pressurizes the block therefore the radiator cap will allow more coolant into the radiator then when you let off the throttle it has pressure) but keep squeezing the radiator hose so if its getting hard compression will typically have it hard within a minute or two. Other test is go drive it get it hot then take the overflow tube off the radiator and connect a hose to the barb that goes into a water bottle full of water if that hose in the water bottle keeps bubbling you've got problems
 

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