My 87 with a 4.9l has been missing like crazy.
started a few months ago. Had the truck for 5p0 miles before this. I parked one night, came out in the morning and went to start it. Shook like crazy, no power. I changed plugs, wires, fuel filter, button and cap mainly just because I shoulda when I bought it and to rule out ignition. All good. Coil tested decent ratings I think. Did a compression check, good readings. Suspected injectors. Bingo 1 bad injector. Replaced it. Truck ran good for a few weeks.

I found out my rear tank doesn't work so I siphoned some of the gas from it to my front tank, about 2 gallons. Truck ran ok for 25 miles. Come home and park it. Go to leave later that day. Shaking like crazy.

Assumed it was bad gas. Pumped out tank, backwashed filter with denatured alcohol, bought and put in 6 remanned Ford injectors. Put them in and still shaking.

I let it run alittle and I noticed it was smoking white alittle. I remembered earlier that when I took out pcv it had some liquid in it. Maybe because truck sat for a couple days but I turned it off before it warmed up. Maybe it's from running that bad gas?

Any ideas?

 

You sure changed a lot of stuff.

What was wrong with the bad injector? What did the plugs look like? Why doesn't your rear tank work?

Smoking white? Does it consume antifreeze?

Check for codes and check your fuel pressure.

 

Was stuck closed. Ohmed and was done. Checked using 9 volt and an injector harness. Old plugs looked good, haven't checked since I put them in. Rear tank never worked as far as I've had it. I switch it to rear but it just reads full and keeps using front fuel pump.
Can't tell if fuel pressure regular line smells like gas because everything smells like gas lol.
No coolant loss. White smoke smells like gasoline.

Has an evap code and an O2 sensor code. Has since I got it.

 

Well tried ohming injectors again. #2 didn't open with my 9v injector harness and ohmed slightly higher. Replaced it with another. Put it all back together and now it won't turn over, just a backfire. Through intake I think

 

Sounds like a faulty PIP in the distributor. Check for a signal.

 

I have a dumb suggestion but make sure your fuel injector wire-harness connections are connected.

I fired my truck up one morning and it was shaking, no power, running really weird. Pulled back in driveway, popped the hood, and I could see #1 injector harness was loose. Tightened it down and it was fine.

The plastic connector doesn't hold that well after years of heat cycling.

 

hey guys wanted to update you. sorry for the delay, had to finish up the farm chores before winter hit, been using my wife's Chevy(shudder)

I went through some TFI diagnosis. got down to either icm or pip I think. this is my pip LED test video if you can interpret results.
still only cranks and sometimes intake backfire.
https://youtu.be/0IoP-7R4HrE

 

Intake backfire is misfiring the plug with the intake valve open. Sounds a lot like a timing issue.

 

timing was okay when it was running. advanced normally on wot. I check rotor while cranking, spun normal, so timing gears should be okay.

 

I'm thinking pip too can anyone look at the video