Is there something that could be going on with a rev limiter / elec issue that would cause my truck to miss / backfire under heavy acceleration in 1st gear only?

 

Anyone?

 

Probably not unless your just running maxed out in first gear and not allowing it to shift. Initially, you might try a MotorVac on it or try a dose of Gumout with REGANE. Make sure it is the one with REGANE otherwise it's going to pretty much a dose of kerosene which isn't going to fix anything. I'd suspect carbon deposits if you aren't getting any codes. There's also a possibility of a COPS going bad too. They will usually last about 85-100,000 miles and if you decide to replace one, replace them all or expect to be chasing similar issues. The best ones come from Ebay and are cheaper for a set of 8 than one Motorcraft costs.

Also note, if yours is a 2006, it's subject to injector failures. You can have catastrophic engine failure with these engines should the injector hang wide open causing a hydrolock situation. If you have anybody that has a code reader, I'd hook it up even if you've never had a CEL.

 

Thanks Labnerd,

I will defintely try the gumout, also do you think running a cylce of deepcreep or sea foam through the top end would help clean out some of the carbon? I am just about due for a plug change which I am not real happy about due to the nightmare stories I have heard about, but I will probably go ahead and change out the COPS at the same time, about how much should I expect to spend on the COPS

 

Before spending any money on treatments I would also recommend that you have your truck scanned for codes. Most auto parts stores do it for free. Post back the results. Be sure to ask for the code numbers and not the descriptions. Ie. P0305.


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I will do that tonight and post the code #'s

 

Ok took my truck to A.Z. and they plugged it in and it pulled not one code....I have no CEL light on....I went ahead and bought a bottle of gumout w/ regane like a previous post had suggested...I am open to anymore ideas if anypne has any. Again the issue is a series of sputters and small backfires in HIGH RPM's in first gear or when I punch it on the highway to pass someone
and then it shifts and its off to the races and it runs thru the rest of the gears w/ NO issues.....

 

How olds your fuel filter? Dont sound exactly like a bad fuel filter but close enough. If you haven't ever changed it try that... Your supposed to do it every 30k.

 

Just changed it about 2 months ago thinking this is what was causing my issue, I also cleaned the MAF and the TB with no luck.....

 

Put it in first and watch the tach, safely please, and drive it till it sputters and all. Note the rpm and post back.

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I wil try and do that tonight, now I say it does it in first gear, but I am assuming it is first gear b/c it does it when I take off from a dead stop and accelerate hard, do you want me to actually have it in first or just do my normal hard acceleration and just note the RPM at which it happens? I will actually attempt to take my camera with my so I can film the tach and you can hear what it is doing...

 

If it does it before hitting the rev limiter we will see it in the tach. It might be hitting the rev limiter before it shifts gears and then goes nuts trying to figure out which gear to select. Do a run in drive, do a run in 1st and then do a run in drive but let off the gas when it starts to miss to see if it shifts into second.

Regards

Jean Marc Chartier

 

Ok, so I went out and did several runs to try and record the tach and the sputtering. I did all three runs like JMC said to do. Unfortunately the mic on my camera did not pick up hte sound very well.

Run 1: Put in first and ran it up to 4k rpm no sputter at all


Run 2: Take off from a dead stop, and it sputter and small backfires aroun 4K rpm kicks back in and accels up to 5K RPM befroe shifting normally. Like I said you cannot really hear it at all on this video. I will try again when I can get around less traffic so I can make several runs at it....