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Help with 1990 f150, have searched, black smoke running rich

No problem, glad to help.

Go ahead and pull the codes again, let's see what you have.
There are some tricks for the egr if you come up with a code 32

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And if I plug in the egr that’s off the motor right now, it pops 85,34


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dustybumpers

don't play well w others
84 is the vacuum line with the solenoid running from the throttle body to the charcoal can to the vent on the gas tanks
31 is a drop in voltage on evap sensor egr
34 is similar.
If you still have the egr on the plenum, take the sensor off the top, and put a rubber vacuum cap on the post that reads the diaphram.
Bolt it back down

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84 is the vacuum line with the solenoid running from the throttle body to the charcoal can to the vent on the gas tanks
31 is a drop in voltage on evap sensor egr
34 is similar.
If you still have the egr on the plenum, take the sensor off the top, and put a rubber vacuum cap on the post that reads the diaphram.
Bolt it back down

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It was 85 that it threw- good to know on the egr, I’ll try that vacuum plug trick right now


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dustybumpers

don't play well w others
It will take a few key cycles for the code to become silent. The vacuume solinoid/line to the charcoal can over by your battery is actually a good thing, and next time you get to a junk yard, should pick one up. They keep the moisture out of the top of your tanks

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It will take a few key cycles for the code to become silent. The vacuume solinoid/line to the charcoal can over by your battery is actually a good thing, and next time you get to a junk yard, should pick one up. They keep the moisture out of the top of your tanks

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68e1b22b19dc9aacceefc3d3d6277867.jpg
this doesn’t have a internal vacuum port?



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It will take a few key cycles for the code to become silent. The vacuume solinoid/line to the charcoal can over by your battery is actually a good thing, and next time you get to a junk yard, should pick one up. They keep the moisture out of the top of your tanks

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Did the vacuum cap, it’s still popping the 31,85 but weirdly the check engine will come on, if I rev it up- it goes away. Then back on when it’s come down a bit lol


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dustybumpers

don't play well w others
You have a bad egr switch on the other end. Motor is out of that truck of mine,so no pictures. Sorry. I'll try to guide you there. Standing in front of the truck, look at the coil. In front of the coil facing you is a unit with 2 wires coming out the end facing you, 2 vacuum lines into it. That also has a air filter on it, but cant be replaced.. try unplugging it, and cleaning the terminals.
Check the vacuum lines aren't broke. Green goes to egr, black is ported vacuum. Both go behind the plenum, and are very fragile

Next look on passenger fender at your reserve can. Should be red and black lines. Make sure they are good. Look can over for rust through. If it has holes find a plastic can in the junk yard from a 93 or newer truck


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You have a bad egr switch on the other end. Motor is out of that truck of mine,so no pictures. Sorry. I'll try to guide you there. Standing in front of the truck, look at the coil. In front of the coil facing you is a unit with 2 wires coming out the end facing you, 2 vacuum lines into it. That also has a air filter on it, but cant be replaced.. try unplugging it, and cleaning the terminals.
Check the vacuum lines aren't broke. Green goes to egr, black is ported vacuum. Both go behind the plenum, and are very fragile

Next look on passenger fender at your reserve can. Should be red and black lines. Make sure they are good. Look can over for rust through. If it has holes find a plastic can in the junk yard from a 93 or newer truck


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I actually happened to have a spare egr switch. When I did the swap a year or so ago I kept all the solenoids and switches and coil just incase, it worked though! Running with no cel, you should change you’re name to the eec-Iv whisperer lol.


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dustybumpers

don't play well w others
Lol. I have worked on a "few" old Ford trucks

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Lol. I have worked on a "few" old Ford trucks

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One last question considering how
My plugs looked. And that first thing when it fired off this morning it blew this out
b41583d1ee47a42dfde1b61d324363e2.jpg
could it have clogged the 02? Would I have to wait for it to go into closed loop to find out?


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dustybumpers

don't play well w others
It is just from running rich for a bit. I would run it for a tank or two, then pull a plug or 2, see what you have.

02 sensor should clean itself. It will throw a code if not. Worry more that the cats are clogged than anything.
I think you caught it in time .no need to worry yet. If you smak the muffler with your hand good and hard, and it rattles like it has glass inside, you cat is done.

As I said. Wait for codes first tho. Dont throw money at it

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