Guys, I need a little more help if you can. This truck is gonna drive me crazy before I get it running right. 04-FX4, 3V 5.4-98k miles A few months back (94k miles), the truck was lugging, missing, and would sometimes die while driving it. My RPM's were way lower than they should be, and overall it just ran like crap. It also had a drivers side oil leak. I changed my plugs, oil filter, and fuel filter, but it kept running the same until I cleaned the MAF sensor and TB. After that it ran perfect. I also changed the DS valve cover gasket, but it still leaks oil. Three days ago I left it idling to run in a store, and when I came back out it had died. It cranked back up, but the CEL came on, and it idled rough. Now though, the RPM's are higher than normal (800-1000 in gear, 1000+ while in park). If left running, it will start to miss until it dies. The codes it threw were P0171 and P0172 (both bank one lean). I have read that the MAF is common for these codes, so I was planning on cleaning it, the TB, and changing the fuel filter again today. I'm not sure though, because the last time that was the culprit, the RPM's were really low, but now the RPM's are higher than normal. Any help here would really be appreciated. Thanks, Jake.
Ok, have you had you injectors changed yet? 04/05 models sometimes have injectors that stick open and will cause your motor to idle and run rough and it will hydrolock your engine. Probably time for a tune up. Change spark plugs, replace coils, PVC valve, and do you have a cold air intake? If you do that would cause your engine to run lean and detonate.
Get it to a dealership asap if you have not got the injectors checked and replaced. It's a warranted part for a 100,000 miles. 04-05.
Thanks for the reply..... I don't have a CAI on the truck. It has a paper filter that is fairly new and in really good shape. I just changed the plugs 4k ago. Are you saying that I should just replace all the coil packs? From what I have read, the PCV valve on these trucks is part of the intake manifold, and cant be replaced unless you change the manifold, but I am not sure. Also, when I cleaned the TB, I think there was a little bit of oil in the intake.
Check your injectors like he said. It's a common problem that they get stuck open or closed which would cause a rough idle and the truck to die. If they are stuck open then it could hydrolock the engine and your out a lot more money
I replace it all. Lol but I don't risk anything. Reason I said replace coils is because the boots sometimes rips and cause the engine to miss and if your truck is burning oil replace that PVC valve. It is replaceable. I just got to find how tos on it cause I have not got a chance to do it yet. They should be replaced every 60,000 though. But the main thing I'm worried about for you is your fuel injectors. Get those looked at asap.
I don't think it matters cause you have less then a 100,000 miles on it and I seen it happen to someone before that just bought the truck at 70,000 miles. Injector 3 was sticking and ford replaced it. This is not something you should wait to get checked.
If you keep driving with a stuck injector (if thats your issue) you could bend a rod an need a new short block. Dealership should cover it so take it in before 100k
