I posted this question in another forum and someone recommended that I post it here as well.

The full description of my problem can be found at: https://www.f150online.com/forums/sh...hreadid=111592

Basically, my truck was running fine, I reflashed successfully with the Hypertech III, then I tried to start it. It did something akin to backfiring. I immediately reflashed it to the original, factory state, and now the truck starts fine, but has a loud and persistent knock.

So my question is this: Can anyone imagine a scenario where really bad timing would lead to something like a backfire which could, in turn, cause mechanical damage to an engine?

 

A "loud and persistent knock?" Get that motor looked at *immediately*, and have it towed, don't drive it, don't start it again until it's in the hands of a good mechanic, preferably a dealership. That sounds like a bearing may have spun, or a spark plug cracked or broken off into the combustion chamber, etc.

Once you return to the factory program, that's it, you're back to stock. There's no way for anyone on a message board to tell you if you damaged your engine with that device (though I really doubt that), that obviously requires inspection of the vehicle & maybe some testing.

I have not read that thread as I don't have the time, but it sounds like what you experienced when you originally flashed your PCM with their programmer could *potentially* be due to Hypertech's generic tuning. Meaning, in this case the factory program your particular truck just happens to be too different from the generic compromised "one size fits all" program in that Hypertech unit. They aren't like Superchips, where each unit contains hundreds or thousands of programs, a different one to match each different factory program in every different vehicle the unit works on.......Hypertech gives you one program to run on all similar vehicles, and that can sometimes cause anything from a small power gain and ok driveability, so everything is fine, to a power loss, detonation, the fuel control data to be handled incorrectly causing backfire and/or raw fuel in the pipes (which you'd detect by smelling a gross over-rich condition), etc.

Now of course I'm just guessing here, but we have seen that kind of thing happen before. And in those scenario's, you generally don't have any kind of vehicle damage as a result of using a program that is not properly matched to the vehicle, I don't remember ever hearing of that happening. Once you go back to stock, you're on the factory program and the symptoms are relieved. You may have had something let go in the motor just coincidentally at the same approximate time, we have indeed seen that kind of thing happen before too, and that's upsetting for everyone of course. Or, it is perhaps possible to have some wierd isolated case of getting a backfire and that backfire causing something to crack or break off, or cause a rod bearing to spin, etc. and thus cause that knock you hear. It's possible, not probable, there's just no way to know without inspection & possibly using a borescope, etc.

There's literally no telling what has actually happened at this point, that can't possibly be solved here. But with *any* engine exhibiting a "loud and persistent knock," the correct thing to do is to NOT LET IT RUN ANYMORE until you get it to a dealership service deparment or top-notch Ford mechanic *pronto*. Have this diagnosed properly, don't continue to just drive it like that, as you may ruin the engine. You could have spun a rod or crankshaft bearing, which would cause a loud and persistent knock (detonation doesn't do that), or if part of a spark plug blew off it could be rattling around inside the combusiotn chamber, bouncing off the top of the piston & damaging the cylinder bore, piston, valves, etc., it could ruin the engine entirely. Whatever you do, do NOT continue to run the engine with a "loud and persistent knock," have it towed to a service facility immediately.

Again, this is *all* just guesswork, but with a "loud and persistent knock," getting that motor looked at **right now** needs to be your first priority, and worry about the potential cause after you make every attempt to save the motor & limit any potential damage, as the owner of the vehicle that is your responsibility to do everything possible to limit any possible damage, so you can't contionue to drive it like that, the engine should not be run again until it's in the hands of a professional.

I don't mean to alarm you, but that's not a good sign having a loud persistent knock in the motor. I'm assuming you aren't talking about "pinging" under hard acceleration, I'm assuming you mean a loud knock anytime the motor is running. I hope it's just something minor.

Sorry we really can't be much help solving this here, this is something a mechanic needs to check out for you, and now. Then you can talk to Hypertech if the mechanic feels the symptoms are related. Again, that's possible, but I've never seen that happen before where a Hypertech programmer has caused a backfire *and* actual engine damage. I don't like Hypertech as their results just aren't comparable to Superchips, but in all fairness, I don't remember ever hearing of a case where someone used their programmer, had a backfire, returned to stock, and had engine damage.

We wish you all the best, good luck with this!

 

I had already decided not to start it again; it will be towed to a competent mechanic.

Thanks for your help.

Greg

 

Hi Greg,

You're more than welcome, & sorry I'm not really able to be more help. All I've done is basically tell you what you already know, which is that the motor needs to be looked over by a pro.

Let us know what happens, what they find, etc., & good luck!

 

The root cause of my problem has nothing to do with reflashing the firmware.

It turns out that my engine has had the same head gasket failure that's so common on the 4.2 V6. The pickup has been a second vehicle for the last few weeks. I had left it sitting for several days before starting it right after reflashing the firmware with the Hypertech programmer. While it was sitting, coolant was leaking into one or more cylinders. Fluid doesn't compress well. When I tried to start it, something broke. Possibly a rod. The 'backfiring' was actually more of a belch; I guess that's what an engine with fluid in the cylinders sounds like.

Anyway, my truck ran great for over 6 years, and just as I finished reflashing the firmware, it suffered a completely unrelated major breakdown. What's the chance of that happening?

Thanks for your help.

Greg

 

Similar ot me installing a TransGo shift kit on my 4R70W, and at the same time that Iwas working on it, 4th gear (Overdrive) happened to wear away. It was a know problem on the old transmissions, but it happened right when Iwent to mess with my tranny. So we are like that .001% of people that have problems like this . Just get it rebuilt or drop a V-8 in it.

 

Hi Greg & Beastie,

Greg, thanks for letting us know what happened, & very sorry to hear of your misfortune.

Both of you gentlemen have an unrelated failure at the same time in common, and that is the worst thing to try to explain to a customer, I hate it when that happens. It upsets *everyone* involved when this happens, from the vehicle owner (of course!) to the vendor or manufacturer supplying whatever was just installed, in your case the Hypertech, in Beastie's case a shift kit.

This thread should be bookmarked as an excellent example of the fact that these things do happen, and when it happens at the same time as installing a modification, it can be hard for the vehicle owner to accept that it was not actually related to the part or parts just installed. Nobody wins in this kind of situation.

Thanks for letting us know what happened Greg, & best of luck in getting this taken care of!