My f-150 is an 05' with the 5.4 in it. I put the edge evo in it a little before fall. It ran fine until it began to shift very strange. It would shift to very low rpm and sometimes has trouble shifting out of gears. The first time it had trouble shifting my edge read cylinder 5 missfire. Then today, my o/d off light appeared and the codes P0740 and P0743 showed up. I dont know if this is the chips fault or what but something is apparently wrong with it. Anybody have an idea? And does anybody know what these codes mean? Thanks for all replies

 

Both codes relate to your Torque Converter. P0740 is Torque Converter Clutch Circuit Malfunction and P0743 is Torque Converter Clutch System Electrical.

I would return your tune to stock (level 0). You can clear the codes with the Edge at any tune level, so do so. If the trouble reoccurs at stock (just leave your Edge connected so you can monitor this), you'll know the Edge is not at fault. I doubt your problems are caused at all by the Edge or its tunes, but this is a way to find out.

I also doubt the Cyl 5 misfire was caused by the Edge either. How many miles have you got on your truck? How old are the plugs and the coils? Your truck is one (like mine) that is effected by the fuel injector problem, and that could possibly be a factor too.

- Jack

 

I have close to 49,000 miles. The shifting problems began whileI had the chip on level one, and I had heard of the fuel problem and an edge evo + CAI, so that is why I was blaming it partially on the chip. I have a K&N CAI, by the way, so that mightve worsened the problem. I decided to put my truck to stock and the problem still existed, but I didnt know if the chip hurt the motor or not. My truck runs fine at idle but when I get goin it runs rough and acts like it doesnt have any power. Oh, and when the Cyl 5 missfire happened my emissions systtem or service engine soon light appeared. i appreciate your help, finally somebody replied haha

 

Oh, and we got the truck with 25,000 miles on it, and we have not changed the plugs and coils.

 

If the programmer set the tune back to stock, and the problem continues, the problem is in your truck, not the programmer. And, the CAI is NOT doing you any favors at all on a 2005 model truck. You've probably seen the posts on "running lean", and I suspect that is what you are doing. This CAN damage the engine.

It is normal to get a Check Engine light if you have a problem like a cylinder misfire. I think you MAY have to get 3 codes to make that thing show up (I could be wrong here), but, I suspect there were several codes.

I also think a lean running engine can cause a misfire because the high heat causes damage to the plugs. If you pulled the #5 plug, (it's the one in front on the driver's side, so it's easy to get at), you'd be able to check for damage (blistered, white insulator, eroded electrode and no deposits, or, melted electrodes). Be sure to follow the TSB on plug removal if you do this job yourself!

But, the Torque Converter codes should not be related to a lean running engine at all. And, since they are "electrical", it sounds like a "control" problem rather than a mechanical problem in the converter. There is a feedback circuit that supplies information to the PCM from the Torque Converter Clutch. A malfunction here, such as an open or short circuit can set the P0743 code, I think. This is about all I know about it and, I would take my truck to a trusted shop if I had this problem.

- Jack

 

Yes, I've heard of the running lean engine, but I woulda thought it make it longer than this. If it damages the engine, what damages would it be, and are they repairable?

 

And what woulda caused the torque converter problem? And would it cost much to get this fixed? I appreciate your help on this cuz its really been buggin me

 

Nothing's cheap when it comes to a vehicle. Just "suck it up" and prepare to spend some money. I DON'T expect the several thousand dollar repair job here, but I suspect the problem COULD be inside the converter, where ever the faulty sensor/component is. It will cost to fix this - you can bet on it.

As far as what causes the problem? Who knows? Loose wiring? Corroded corrections? A sensing unit that has failed? I don't see a "tune" causing this at all, tunes should IMPROVE the life of your transmission.

Whatever the cause, you DO need to get it fixed. Otherwise, you are looking at much more serious damage down the road.

I'll put it this way: Did you ever have a tooth cavity that you ignored? What started out as a simple filling became a crown or an extraction.

Lean engine problems are always repairable. You can simply replace the engine in the worst case scenario. But, you can damage the plugs, then the pistons and on and on with a lean burning engine. It has localized "hot" spots that are not good for a long, happy life. A damaged plug can cause a cylinder misfire.

- Jack

 

Alright well that pretty much sums everyhting up for me. Thanks, you've been a lot of help

 

The running lean would have happened with the aftermarket intake, even without the Edge. It is a problem with many of the 04 and 05s when a CAI is added. Yes, it will cause permanent and expensive damage if allowed to continue. Either put the stock intake back on or get custom tunes with a CAI.

 

Well I have the chip set back to stock until I get it fixed. I'm just hopin theres nothing wrong with the actual converter cuz it aint shifting as well as it did before. But I'm planning on getting it fixed soon so maybeIcan get everything back to normal and wont be too pricey. I will definitely keep the chip on stock til i get custom tunes. I appreciate yalls help with diagnosing this problem.

 

Your misfire condition could also be caused by a faulty fuel injector. The 2005 5.4 3v fuel injectors have an extended warranty on them (only 2005). I know, had one hang open and hydrolock my engine. See the bottom link in my sig for more information.