I have an '88 2.9 that will fire right up every time, after about 30 seconds starts kicking out what looks like condensation that eventually turns into thicker smoke - albeit not the super thick sticky kind with a blown head gasket. It'll kick out the smoke for almost as long as it sits and idles, but driving for ~5 minutes makes it go away and for the most part stays away until the engine cools down. First though was a small gasket leak that was sealing when warmed up. The kicker is I've never seen anything in the oil, nor lost any coolant. Runs pig-rich and gets about 9 miles to the gallon. Has new plugs, wires, and I just replaced the o2 sensor. Just pulled and cleaned the injectors and checked all their continuity. Replaced o-rings and pintles and cleaned out the upper intake and throttle body while it was off. Has a new MAP sensor, can't find any vacuum leaks, fixed the fuel pump harness, and compression in all cylinders was consistent (although I can't remember the readings - this was my first check the day it went down). I'll be pulling the cap and rotor (although he claims it was new) and checking the timing (although it hasn't been touched since it was running fine) this weekend. Thoughts? Possibly a ECU or coil pack starting to go? Because I thought I had basically nothing to lose, I ran a head gasket sealer and a radiator sealer last summer. Still starts as soon as the key is hit, idles at just under 800, and pulls fairly well until it gets choked out and then bucks for a second until the computer re-calibrates. This was all catastrophic - read the back story below if you want. I'm at a bit of a loss at this point. Should also point out a separate issue with the OBD1 harness - previous owner may have swapped locations on a couple wires? When I plug in a reader and run the diagnostics it just turns on the fuel pump relay and leaves it on. Never shuts off. No other solenoids turn on. Not. Helpful.

So last summer I bought this super well maintained truck from a guy who apparently was a motor home mechanic (Ford's mostly). I said "look, I don't want a project" and he said "oh no no no, this isn't a project." This is a dual tank version. Fired right up, idled great, smooth acceleration, everything felt great. He claims he had just put gas in the second tank. I drive it home and have to change over to the second tank fairly close to home. The next day I fire it up, drive up the hill at the end of my driveway, go about 1/4 mile, and all hell breaks loose. Huge plume of white smoke, engine dies. I get a push into the closest parking lot. When I hit the key I immediately dump a half a gallon of fuel under the cab. What I discover is that he has completely messed up the fuel line clips - forcing the 5/16 onto the 3/8 and vice versa. I blew a line, seemed to have clogged my filter, blew out my regulator, and fried the high pressure pump. I also discovered that the wiring on the harness that attached to the fuel relay was massively frayed and likely arcing. Fuel system is back together, new high pressure pump, filter, secondary high flow sediment filter before the high pressure pump, new fuel pump relay. I installed a used regulator that was working fine and still seems to be working fine.

 

Have you checked your fuel pressure to see what it's reading at?

Not sure if the truck has an intake air temperature sensor or not, but that can cause issues with fueling.. So can the coolant temp sensor on some engines..



GB :)