E99 drivability issue

[bryan.d]

I have an E99 that is giving me trouble. It starts and idles fine until it get warm then it starts to miss like it running on 4 cyl. Appears to start missing on one cyl. at first then gradually gets worse. I pull over and let it idle with a little revving it up there is some greyish/white smoke from the tailpipe and knocking and it clears up and idles fine. No codes with OBD2 reader. Then I proceed to drive on and the same missing starts again. The symptoms started all of a sudden while driving felt a stumble then the problems started. I have been searching this site and others with little luck. The truck has 248k and i purchased it with 170k. Mostly stock with the exception of exhaust, 6637 air filter, and SCT canned tunes. I have replaced both UVH (motorcraft)and one VC gasket (felpro. waiting for the other to come in). One of the UVH and VC gasket had a burnt terminal(drivers side). Oil level is good. Fuel is good and clear. Hopefully someone with more knowledge than me has a little insight on the problem. Thanks for reading and I apologize for the the long read.

 

[Arisley]

As stupid as it sounds, have the alternator load checked.

 

[bryan.d]

Funny thing you should suggest that i check the alt. the battery light on the dash has been flashing intermittingly for a couple of months now. I didn't think anything about it because the batteries have been staying charged (no sluggish starting) and voltage output is over 14 volts. I will get it checked out today.

 

[Arisley]

Check out the big single terminal on the alternator. That connector likes to break, it will hold a "connection" because of the heat shrink. It will sorta work.

 

[bryan.d]

Turns out the alternator was bad. Peeled the heat shrink off the big terminal and it was good. Installed new alt. seems to be ok. Still have a slight miss when hot, but not as bad seems like one cylinder is at about 75%, comes and goes. One other thing i noticed after the alt install is that the fuel pump doesn't stop while the glow plugs are heating up.

 

[bryan.d]

Just finished messing around with the truck. After attempting to head out this am thinking I had the problem fixed. Did the exact same thing just took a little longer to act up. I kept having a feelong it was fuel related. I had a hi volume high press. electric pump from a previous race car, that i decided to put on for ****s and giggles. Guess what no miss and runs a hell of a lot better. Fixed...... What would be an upgraded pump to put in as i will be putting in some larger sticks in the near future?