I have a 2004 F150 Lariat 4wd with the 5.4L that occasionally hesitates on take off. It usually only does it on cold mornings or when I'm pulling a trailer. If I stop at a stop sign or get in for the first take off I can hit the gas, engine revs but the truck doesn't move, and then it kind of jerks me forward. It worries me sometimes when I'm trying to pull out intro traffic. I have 116,000 miles on my truck. It started this about 3 years ago when I was around 70,000 miles. I have never had an engine light or anything come on. When it first started I took it in for an oil change and the dealer (without knowing of my problem) said I needed a new mass airflow sensor. I took it to my local trusted mechanic who said he could just clean it so he did. I had it start happening again on me this past fall so I took it to him again. He drove it around and of course it never happened for him as it was a warm day and the truck had already been ran, plus no trailer. Any ideas what is going on here? My only non stock items are a drop in K&N filter and I have the muffler removed with a 24" echo tip welded in place under the bed. I had both items for a year or so before I noticed this issue.

 

Did he clean the MAF again? K&N oil is known to foul the MAF.

How many miles are on the spark plugs? When was your last transmission service? Last fuel filter change?

 

He did clean the MAF again as well as my K&N for me. Stock spark plugs. Never had the transmission serviced. The fuel filter was replaced at 100,000 miles.

 

Funny you say that bc I have a 08 screw with 30,000 miles on it and I thought I was noticing it doing the same but it seems to be around 30-40 mph with mine. i have to be cruising at that speed then try to accelerate for it to happen. doesnt happen all the time just every once in a while. Almost like the computer dosent quite know what gear it wants to use. I wounder if its a trans problem, computer problem, or just something that cant be fixed.

 

You have 116k on the original spark plugs and transmission fluid? Don't you think you should get caught up on your periodic maintenance before trying to troubleshoot a minor drivability issue?

 

No I do not.

 

there's the second issue, the first is the lack of maintenance

how dare you think your truck shold run 100% when you FAIL to maintain it 100%

 

What could be the issue in my case then? Only 30,000 miles.

 

if you go back to your thread, you'll see why many of us feel it's operator error

 

Are you a certified mechanic? Because I've had my truck in for oil changes every 5,000 miles at my dealer and they sign off on these items each time. I've also had another dealer do the same one other time as well as my local preferred mechanic.

Keep in mind this is an ongoing issue for the last 50,000 miles. BTW it did it hesitated off and on at about 40mph on the way home today.

 

Spark plugs. As the plugs are used longer, the gap slowly increases. How would that not affect the performance of your engine? How about weak coil overs? That would cause issues with performance as well. tarajerame is right, look at the basic maintenance and, if the problem shows itself, ask for help.

On that note, why would you ask for help and then turn down any suggestions made? Basic maintenance is not just changing the oil, though that is part of it.

 

he doesn't want honesty, which is why he's been getting ripped off thus far, he wants asugar coated answer, and he's been added to my ignore list...

 

Weren't the 04's the ones that have the injector issues? Could be plugged cats from excessive fuel dump.

 

I've specifically asked my dealer about the plugs in the past and they came back with they were fine.

BTW it wasn't tarajerame's suggestions of what to look at that bothered me, it was his rude attitude. I actually thought it was the transmission at first, but I've come to believe it is possibly a sensor and/or computer issue.

 

Don't let that guy's attitude offed you, you just have to consider the source. He is one of those guys that thinks because his post count is higher that he is somewhat better then you. But the truth is he must not have much of a life so he sits on this forum to entertain himself.
Just go and look at his negative comments in the past. You are probably like myself and you use this forum as a tool to receive information and he uses it for social networking. I guess he has never heard of Facebook. Unlike him, most of the people on here are knowledgeable and willing to help when they can and when they cannot they don't make negative comments.