2010 f-150 4x4 5.4l stutters on brake
#1
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2010 f-150 4x4 5.4l stutters on brake
my F-150 when I brake semi hard or sometimes just coming to a stop witll start to stutter and missfire. I've checked for anything loose and have yet to find anything. To fix the issue I just rev the engine and it's all good.
#2
Is the steering wheel shaking or the whole truck?
If just the steering wheel then the front brakes. If the whole truck shakes then it is the back brakes or all of them. It could just be one side on one axle or both.
I only put premium brake parts on my truck because it is worth every penny. I also put the best tires on my truck. Very important because both brakes and tires are what stops my truck therefore I need reliability to prevent liability.
I hope this helps. Free of charge.
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It's not the brakes, it's the engine stuttering and stammering. Last night id did it again and was running rough, and fr the firs time I could smel excess fuel. I've tried reseating every connector I could see.
#4
Have you tested the fuel pressure on the rail? Do you have a cracked fuel injector? Or, are the o-rings dried out? You can turn the injectors a little bit back and forth to check.
Do you have any loose plugs?
Have you modified the engine in any way? Air filter? Exhaust (open flow muffler or diameter of pipe)? Chips? Computer program? Spark plugs? Larger wheels and tires?
Endless possibilities if you have modified your truck and not reprogrammed your computer and other reworking to make the mod worthy and compensatible by the computer.
Modifying your vehicle with these new computers on board can bring on endless maintenance and troubleshooting nightmares.
How about this. Are you using the correct gasoline? By this I mean, A 5.4 must use a minimum of 87 octane fuel (says so in the manual in the glove box). 89 if you are at sea level. This figure is for the compression ratio of the gasoline required to fire properly in the combustion chamber. I never recommend a higher octane (91 or 92 and higher) unless you are trying to correct a problem and even then it is a small amount to compensate for using too low of an octane. The people at high altitude have that kind of problem because there is 85 octane (the cheapest) available at the pump but is not sufficient for a big engine. I live at high altitude and use 87 (midgrade for this area at 6,000 feet - choices are : 85,87,91 where I am due to lower oxygen levels) in my 5.4 Triton 3V. My truck does not run as good at lower altitude with 87 so I put 10 gallons of 92 to compensate and then 89 on the next fill. See the difference?
If you are using the wrong fuel then you need a good clean-out of the combustion chamber and the exhaust - especially the cat. I recommend BG 44K. Wait until tank is 1/8 and put two cans in with a fill-up (22 gallons or more) 87 or 89 depending on the altitude and then drive the truck for 100 miles on the freeway. When entering the freeway on the on-ramp floor it but do not go over posted speed and do not hit anyone in the rear. I recommend also that you exit at the halfway point and get back on and floor it again. This will clean everything to the end of the tailpipe. But you may need to do so twice depending on how clogged up the engine and exhaust are.
Is your EGR clogged?
Is there a leak in the vacuum system? Is your catalytic converter clogged?
See how you need to explain a little better? Mechanics at any shop will need an accurate description of the problem but they can test drive your vehicle with you in the passenger seat to help them bring on the problem more clearly. I cannot do that on this forum. I, by no means, am encouraging you to take it to any shop. They may screw it up worse because most shops in the U.S. do not require certification like they do in Europe. You must be certified there or be under the direction of a master mechanic when working on any vehicle. That must be why their roads are much safer.
My intention was not and is not currently, to aggravate you in any way. I am just trying to help you fix your own vehicle at a very reasonable price.
Please let me know if any of this helps.
Mike
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I totally understand, I grew up in a shop and have a degree in automotive and autobody, the non computerized stuff I've chcked so far.. I ran cleaner through the tank and I travel for work so I use the fuel to the point of 50 miles or less on a regular basis.
My mechanic ability has left off before the computerized generation for the most part (early 80;'s) The truck runs geat except when I brake hard or hit a speedbump a little hard (The reason I wonder if it's a loose connection).. I had servce on the truck at 76k miles and they replaced one coil.. currently it has 138k on it and it's been driving like a champ since, the current mpg shows on the dash at 12.2.. It used to be 16ish with a light load currently there is a moderate load on the truck, the only mod to the truck is armortrac tires which are heavier I lost 2mpg putting these tires on, they are the same size as the factory tires.
Since I'm not in the field of automotive anymore I dont have the fancy tools, I'll do as you had suggested to see what I can find if any. I know there is not any codes on the computer and no engine lights during my time owning this vehicle (I've had it for 5 years now).
Thank you btw
My mechanic ability has left off before the computerized generation for the most part (early 80;'s) The truck runs geat except when I brake hard or hit a speedbump a little hard (The reason I wonder if it's a loose connection).. I had servce on the truck at 76k miles and they replaced one coil.. currently it has 138k on it and it's been driving like a champ since, the current mpg shows on the dash at 12.2.. It used to be 16ish with a light load currently there is a moderate load on the truck, the only mod to the truck is armortrac tires which are heavier I lost 2mpg putting these tires on, they are the same size as the factory tires.
Since I'm not in the field of automotive anymore I dont have the fancy tools, I'll do as you had suggested to see what I can find if any. I know there is not any codes on the computer and no engine lights during my time owning this vehicle (I've had it for 5 years now).
Thank you btw