BTL

I bought this 2004 F150 Lariat last fall and it has been flawless until recently. It currently has 119,600 miles on the odometer.

My first indication something was wrong was 3 or 4 weeks ago. I was in the parking lot of a store getting ready to leave and started the truck. It died immediately and gave me a low oil pressure alarm. I was worried, but started it up again and every thing was fine, had no problems for the next 2 weeks so I figured it was just a fluke occurrence.

Weekend before last we're driving on the highway and suddenly the truck feels like it's missing. It was very noticeable and after about a mile of this I look in the side view mirror and see black smoke coming from the exhaust. Immediately I pulled over into a church parking lot and just as I pulled in the truck died. I was able to start it again and drive it just far enough to get in a parking space, and that was that. It wouldn't start anymore and we had to call a tow.

I normally do most of my own auto work, but since the truck couldn't move I didn't want it in my driveway, so I had them tow it to a local shop instead. That was a week and a half ago, and the shop still isn't positive what's wrong. The mechanic said the plugs were black and he suspects the timing might be off, but he hasn't been able to spend much time on it so hasn't pinpointed the problem yet. He also said it's possible I may need a new engine, which terrifies me since that is not something I can afford. He is really busy right now so he actually suggested I ask around before deciding what I want to do.

So, does anyone here know what may be wrong with my truck? I will probably end up having it towed to another shop for a second opinion but I appreciate any advice in the meantime.

ReaperHWK

What are the DTC codes? That would be a start.

BTL

Ugh, I forgot to ask about codes. I will try to get that information tomorrow.

BTL

Reading a lot about the fuel pump driver module. The black smoke and blaxkblack make me think that's probably not the problem, but man I would be thrilled if it were something that simple.

Aeromech

Timing chain guides are plastic. They can break, then fall into the pan and block the oil pump pickup. When the computer sensed no oil pressure it killed the engine. Have the shop remove the oil pressure switch and screw in a mechanical gauge that actually shows what the pressure is. The gauge in your dash is a simple yes pressure/no pressure that shows switch position and not actual oil pressure. That's why you need the mechanical gauge to troubleshoot this.. The switch is located next to the spin on oil filter.

BTL

Thanks, I'll look into that. Probably will send it elsewhere tomorrow.

Would a blocked oil pump cause the engine to run rich and foul the plugs/make black smoke, etc?

dukedkt442

When the truck stalls, the low oil pressure alarm comes on because there is suddenly no oil pressure, so that could be a chicken/egg situation.

Oil pump would have no effect on fuel mix, but the reason why it may be clogged certainly is. But, it sounds like it's been misfiring for some time now. Timing may be off, welcome to the 5.4 timing club. If that's the case, you would have had to ignore the symptoms (phaser knock, follower tick, chain/guide rattle...). Thorough diagnosis is required.

jefford

First, I'd have a dealer check the ECM/PCM that it is flashed to the latest and address any recalls. I had an 04 that would not run entirely because the processor was bad. I put in a new/refurb ECM from ebay programmed with my VIN and the truck fired right up. The truck was stuck in limp mode, I checked everything it should have run fine, even changed plugs, throttle bodies, sensors. It took better than a week to figure out it was the ECM and the processor specifically.

With that little miles, I'd do a tune up, put in new plugs and possibly new COPS (from rock auto) and the black smoke issue should be isolated.

Expect to do the timing job with this truck. I have another 04 that had the timing chain problem... plastic everywhere.

Have him clean and check the oil pressure gauge, do and oil change and hopefully that will isolate the oil pressure drop issue.

I'd go and talk to a few shops and find a good one that has F150 guys. Might be your local dealer. Might... (:

redfishtd

There is too much info missing here. Need some real codes . PLus some testing .Everything starts with the plugs and boots being replaced correctly . send pictures of these plugs . We need to see if blowby from loose plugs is doing this black traveling up threads is a sign of blowby it will destroy plugs . . Failure to torque wrench plugs 25 to 28foot pounds is common. If these are orig plugs have lisle plug extractor on hand first .
This engine will not tolerate less than a perfect plug job . Diagnosing engine is impossible with bad plugs Nobody can do the plugs as good as the owner if he tries .Your time is free .
It does sound like you had a lot of fuel dumping . Could be bad injectors leaking which is an engine killer . Your maf may need cleaning your o2 sensors may be bad . These items try to control your fuel trims . You should have had all kinds of codes and a cel on dash . This is death to cats ,excess fuel burns them up .You need to get some one to interpret your dtc's and fuel trims .Look at your o2 wires are they on the exhaust manifold and burn't . Clean your throttle body off the manifold .It appears like your system thinks its lean when its not and its adding a lot of fuel .Use maf cleaner and throttle body cleaner not just anything .Not enough info for now.
Yes you must determine oil pressure problem ,drop oil pan and look for plastic .Use manual gauge to check oil pressure .If plastic in there or in oil pu then you must do full timing job .

BTL

Thanks for all of the replies guys. I had the truck towed to a different shop on Saturday. One of the mechanics is the nephew of a co-worker and is a lifelong Ford guy. I'll update when I hear from them.