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F150 engine issue

I have a 2006 Ford F-150 with a 5.4 liter engine. After it warms up past the operating temperature, it dies abruptly upon coming to a halt with no acceleration. The RPMs have to stay up to keep it running. No codes are registered.

You really need to hook a diagnostic computer on it to see what the various readings are from the sensors. Either running too rich or too lean for the conditions or too much air is being introduced from the idle air control motor. I would guess first thing would be maybe checking the throttle area for cleaning the junk out, then possibilities could be the engine temp sensor, air sensor, etc.

+1 for @Bing.

+2 for Bing’s comment.
With emphasis on the IAC system as a possibility.

That this only happens when the engine is warm, and not when cold, makes me think it is running lean. When cold the ECM injects more gas. So when warm the problem is either not enough gas is being injected, or too much air is getting in. Most often it would be the latter. That’s where to place your bets. Unmetered air getting into the engine. Check the rubber parts: for vacuum hoses that are split or leaking or have just come off, and carefully check the air intake plenum area for any signs of cracking or leaks. Esp if it is pleated (so that it can bend) take it off and look at the underside, check for any splitting of the rubber.

It happens when it reaches operating temperature and we come to a stop. It acts like the ignition is being turned off. Then it starts like the engine has overheated with very hard cranking.

That new information changes things. It raises the possibility of something heating up and binding, perhaps a bearing in the alternator, power steering pump, or AC compressor, and putting too much load on the engine to allow it to idle properly, then loading it down when the starter tries to turn the crankshaft to start it.

If you’re up to it and your climate permits, you can check these things yourself by removing the drive belts (serpentine belts) and trying to turn the devices by hand. You’ll want to do it while they’re hot, as that seems to be when the bearing is binding, so I’d recommend wearing leather work gloves, and be sure to read the procedure ahead of time to ensure that you’re properly compressing the serp belts’ tensioner(s).

The dealership that the crank shaft end play is out of tolerance. It’s causing the crank shaft to move back and forth, which causes it to idle and die because it can’t pick up the signal. The vehicle has less than 100k miles on it, and has never been hot or run out of oil or anything. They recommend fixing it with a long block. Ford Motor Company won’t do anything about it, even with less than 100k miles.

That sounds totally bogus. Have they tried replacing the crank angle sensor? These can go wonky when they get hot and cause stalling.

If you indeed have a serious problem w/the crank end play, that could cause this symptom I think, and about the only solution is some form of engine rebuild or a new engine (or long block). It’s possible a repair would work, if the problem is limited to the crank bearings. Likely requiring removing the engine. hmmm … I wonder if there is some possibility this can be repaired without removing the engine, from the oil pan side yielding access to the crank bearings. Before starting down that path, probably worthwhile to get a second opinion on whether the end play is the culprit or not.


If the crank end play is out of tolerance, you can often put in a different thrust washer to get everything back within specs

Can someone give me the email or telephone number of the regional manager of Texas or United States of the service department of Ford Motor Company? I have the customer service number and I did not get satisfaction from them. The dealership told me that there was a service bulletin for this problem, but they could produce it for me in a day and a half since I asked them for it. I am going to pursue some other avenues, but this is where I want to start, because I don’t believe they couldn’t show me the movement of the crank shaft. Either that or they didn’t want to.

A crankshaft with excessive end play can cause some problems but it’s difficult to understand why this problem only occurs when the engine is warmed up and from your post I take it to mean that it’s fine when the engine is cold.

Offhand, I might take a stab at a crank sensor or throttle body related issue. If crank end play is to be blamed then a competent, honest shop should have no problem showing you this issue.
That end play issue can also be easily verified by a non-Ford shop.

As to contacting Ford, that may go nowhere although it’s worth a try I suppose. Manufacturer customer service anymore is pretty much geared towards telling you go back and see the people you just saw.

I agree with the second opinion. What the dealership told you don’t make sence. I had to deal with ford corporate last year, on a 2011 f-150 , because the dealership was screwing me around. They was fantastic!! I’ll look to see if I can find get name and #. I’ll post it in here if I find it. Good luck!!

I would be very skeptical of the shop’s claim that there is excess end play. Did they remove the crankshaft? Or do they contend that the play is so excessive that it can be felt? Enough free play to be felt would break the timing chain or destroy the transmission pump I would imagine. And if they had the pan off to properly check the end play they could have replaced the thrust bearings and corrected the problem. It all sounds quite fishy. .

Don’t waste your time with the dealership. They just want to sell you a new engine. Take it somewhere else to a mechanic who actually cares to diagnose and fix the real problem.

End play can be checked with a dial indicator on the harmonic balancer by prying the balancer backwards and then forwards.

It would be interesting to know how this place arrived at the excessive end play conclusion. That’s a problem usually confined to a manual transmission vehicle that has been hammered hard; assuming the diagnosis even has an iota of truth to it.

Also if it was just the crank sensor, that wouldn’t explain the labored starting issue. Check into what db suggested.