CEL on. 0171/0174. Easiest way to log fuel trims and clear DTCs?

[Jjmoberg]

What is the easiest way to log trims, etc and clear DTCs? Forscan lite and a bluetooth OBD dongle?

I posted in another thread a few weeks ago about adding some E85 to my car to try to run E20ish. I added it without topping off and got a CEL. After figuring out what i did wrong, I have topped off with 6 gallons of 93 twice and the light didnt reset on its own. Its been cold so i havent driven much. But the fuel should be diluted well under E15 by now. I got the codes 0171 and 0174 cleared yesterday and today the light came on again at WOT. Ford pass again says fuel system has reached adaptive limits.

It seems very unlikely that another issue happened at the same time i added the E85. So Id like to clear the codes again and at least see what the STFT and LTFTs are at idle, part throttle, WOT, etc.

I have the battery unhooked for the night and will top off again with 93 and clear the codes at Auto Zone of the battery unhook doesnt clear it. But i need to see whats up with my car that was previously running perfectly.

I have checked visually for loose fittings or cracked vacuum lines. I have an air raid filter, J&L catch cans, GT350 intake tube, and a soler ported throttle body. So certainly there is the opportunity for a vacuum leak. Also possible I am just flowing more air and need a tune to get the MAF dialed in. But i am willing to put stock parts back on once i can scan and reset trims and see if anything makes a difference.

I am planning on a user adjustable flex tune in the next 2-3 months and assuming no vacuum leaks would get the MAF/fuel dialed in at that time.

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[ZXMustang]

Didnt I tell you how to do this a while back - as in not adding the E to the car without topping off with 93? A KAM reset will clear the LTFTs which is your problem right now. Those are all goofed up and going to take a while to normalize. KAM reset will clear those. Battery off might do it. Next time all you need is like 2-2.5 gallons of E then top off with 93. Completely. That will be the right ratio so you wont goober up the fuel trims again. You should get an RTD or MPVI3 and use VCM scanner to log all this. You can reset trans adaptives as well as do a KAM reset.

If you had a tune, you could do a full write as well and that will clear KAM. But currently your LTFTs are probably +35% or more at the moment and the car is trying to pull all that back out and its fighting itself.

 

[Jjmoberg]

Didnt I tell you how to do this a while back - as in not adding the E to the car without topping off with 93? A KAM reset will clear the LTFTs which is your problem right now. Those are all goofed up and going to take a while to normalize. KAM reset will clear those. Battery off might do it. Next time all you need is like 2-2.5 gallons of E then top off with 93. Completely. That will be the right ratio so you wont goober up the fuel trims again. You should get an RTD or MPVI3 and use VCM scanner to log all this. You can reset trans adaptives as well as do a KAM reset.

If you had a tune, you could do a full write as well and that will clear KAM. But currently your LTFTs are probably +35% or more at the moment and the car is trying to pull all that back out and its fighting itself.

i havent added any E since the time I put the 2 gallons in without topping it off at the pump. I have added 6 gallons of 93 twice since then. Id have thought the stft would have started normalizing and pulling the ltft down by now. Ive driven over 100 miles. Im hoping to top up with 93 again, and get the code cleared. Looking for the cheapest or easiest way to be able to scan or log and have some other functionalities. Dont necessarily want to buy a tune device cause the tuner i choose may not use that one.

 

[engineermike]

The torque app and dongle would allow logging but I don’t think it’ll do a kam reset. Vcmscanner will do a kam reset but may present challenges or conflicts if someone else is tuning your car.

Fwiw my buddy put a couple of gallons of e85 in his 2024. Fuel trims went to about 10% and it ran great. No codes or anything.

 

[Jjmoberg]

The torque app and dongle would allow logging but I don’t think it’ll do a kam reset. Vcmscanner will do a kam reset but may present challenges or conflicts if someone else is tuning your car.

Fwiw my buddy put a couple of gallons of e85 in his 2024. Fuel trims went to about 10% and it ran great. No codes or anything.

I know i screwed up initially adding 2 gallons and not topping off. I just cant believe that hasnt trimmed out after 12 gallons and 100-125 miles of driving. So that makes me wonder if i have a leak or my set up is sitting at positive ltfts all the time and the E just pushes it over the edge. I need to be able to see the trims. And hopefully clear KAMs when needed.

Anyone have thoughts on Forscan lite?

 

[Jjmoberg]

I forgot i had a Forscan compatible OBD2 cable from when i bought my F250. So i put Forscan on my laptop and went to see what was up. I cleared the adaptive and the DTC and started it. I let it idle a good long time and warm up. Cant drive today cause its cold and rainy and Cup2s. The idle STFTs were around 30%. Went down to around 10% and then the LTFTs came on around 7-10%. I cleared the adaptive again and STFTs came up around 30% again. I cant fathom that 2 gallons of E a month ago is affecting fueling at this point after adding 12 gallons of 93.

Not sure what else to do tomorrow other than drive it easy and top it off with 93 and see how the trims look.

If unchanged i would put all the stock stuff back on this weekend and see if that fixes the trims. If it doesnt i guess i would have the dealer look for whatever else is wrong.

Any other ideas welcome.

 

[engineermike]

At idle STFT can do some odd things and drift a bit. I wouldn’t base much on that. Drive it around a bit and if it’s hovering around 10% then that’s probably ok. They’ll drop more as the ethanol gets diluted.

What parts are you referring to swapping out?

 

[K4fxd]

GT350 intake tube, and a soler ported throttle body

Are you tuned for the 350 intake tube and solar TB?

 

[Jjmoberg]

At idle STFT can do some odd things and drift a bit. I wouldn’t base much on that. Drive it around a bit and if it’s hovering around 10% then that’s probably ok. They’ll drop more as the ethanol gets diluted.

What parts are you referring to swapping out?

Are you tuned for the 350 intake tube and solar TB?

I am not tuned at all. In theory the 350 intake tube is the same ID as the M1 tube just without the resonator. The TB is certainly flowing more air and likely a fair amount of that is off idle and mid range.

i would swap the air filter, intake tube, TB, and oil separators back to stock parts. I would only do that after some miles and if the LTFTs settle at a number that seems unacceptable. I would especially do it if it kicks the CEL again.

i just cant imagine theres much E left in there. Like maybe half a gallon. I have run it down to half a tank twice now.

I suppose the proper order of things if the trims arent decent after driving would be swap the factory parts and re check trims. If they are bad still i can certainly run this tank dry and refill and see if they get better. If not i would guess its got a leak somewhere. If the trims go to near zero with factory parts i can add everything back one by one and see what pulls it off. Could be a leak at the connections on the intake tube or the lines on the oil separators.

And maybe it settles at +10% and we just say thats cause i need a tune for my parts.

 

[K4fxd]

I think the insert causes a 10% trim error. So that is about correct if it does settle there.

You should get tuned for the intake tube. I do believe Solar claims no tune required but IDK.

 

[Jjmoberg]

I think the insert causes a 10% trim error. So that is about correct if it does settle there.

You should get tuned for the intake tube. I do believe Solar claims no tune required but IDK.

They do. I would tend to think that's accurate, but that would be based off of my LS1 experience not Fords….

if I can get it to settle at 10% after all the E is out of the tank I would be happy. I am getting a user adjustable flex tune by early summer at the latest. Will ask the tuner to dial in the MAF on 91/93 before we move on to E tuning.

 

[Jjmoberg]

At a loss for what else to do other than throw factory parts back on it. Drove another good bit this week after i reset the adaptives. No CEL came back, but i was being easy on it. Hooked up Forscan in the garage. The LTFTs are both at 28%. STFTs are actually near 0 at idle, which i know doesnt mean much. I reset adaptives again just now, but i put 7.5 more gallons of 93 in it earlier this week. So thats around 20 gallons total since i put the 2 gallons of E in it without topping off a month or so ago. Trims shouldnt be off like that i dont think after all this time unless i have a leak. Unless someone else has another idea

 

[SheepDog]

At a loss for what else to do other than throw factory parts back on it. Drove another good bit this week after i reset the adaptives. No CEL came back, but i was being easy on it. Hooked up Forscan in the garage. The LTFTs are both at 28%. STFTs are actually near 0 at idle, which i know doesnt mean much. I reset adaptives again just now, but i put 7.5 more gallons of 93 in it earlier this week. So thats around 20 gallons total since i put the 2 gallons of E in it without topping off a month or so ago. Trims shouldnt be off like that i dont think after all this time unless i have a leak. Unless someone else has another idea

Get some brake cleaner or carb cleaner and start spraying short burst around the intake manifold, throttle body, basically anything post MAF while watching your fuel trims (engine running). If you have a leak, the trims will go negative when the cleaner is sucked into the "leak' area.

Also, isn't the GT350 intake tube a larger diameter than the OEM MACH1? The MACH 1 has a spacer sleeve in it, where the MAF sensor sits, but I don't think the GT350 tube has that, which would make the diameter of the tube around the MAF sensor larger.

 

[Jjmoberg]

Get some brake cleaner or carb cleaner and start spraying short burst around the intake manifold, throttle body, basically anything post MAF while watching your fuel trims (engine running). If you have a leak, the trims will go negative when the cleaner is sucked into the "leak' area.

Also, isn't the GT350 intake tube a larger diameter than the OEM MACH1? The MACH 1 has a spacer sleeve in it, where the MAF sensor sits, but I don't think the GT350 tube has that, which would make the diameter of the tube around the MAF sensor larger.

Supposedly its the same diameter as the M1 tube is with the sleeve installed from what i read. I didn't verify but will when i remove the 350 tube. Everything is tight so i am likely to put the parts on and then let the dealer handle it if the trims still suck.

 

[SheepDog]

Supposedly its the same diameter as the M1 tube is with the sleeve installed from what i read. I didn't verify but will when i remove the 350 tube. Everything is tight so i am likely to put the parts on and then let the dealer handle it if the trims still suck.

Just put the tube section from the MACH1 back on the car and try it out. takes 5 minutes. The GT350 never had the carbon filter nonsense in it, and the sleeve is in place on the 22+ MAch1's to hold that carbon trap in place

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