More fueling issues

[Angrymongoose]

This car is the gift that keeps giving this year.

So I have a weird issue. On longish drives the long term fuel trims on bank 1 start to climb. I made about a 45 minute drive yesterday and towards the end it started creeping up. They started at 1.12 or so at 75 to 80 mph. It climbed to 1.14 at the end of that drive. The stft on bank one was pretty set at 1.03 for the last 10 minutes or so of the drive.

I made the return drive about 4 hours later. The stfts stayed at 1.03 and by the end of the drive the ltfts on bank 1 had risen to 1.2 or so.

Thia is all at steady rpms cruising at 75ish. At idle the ltft is 1.1 which I know is a bit elevated already.

I replaced injectors earlier this year due to a p219a code and that seemed to fix that issue. Im wondering if I have a slightly plugged injector again, or if its a whole new issue.

 

[Ta2dResqr]

You are trying to diagnose a .02% ltft change? That is minuscule. I suppose you could try some fuel injector cleaner. Anything could be the cause of that though. Colder air being more dense and a dirty MAP. Lower quality gas. Change in fuel formula because of the season. Tiny air leak. Honestly, 1.2% is so small, I would not even look at the number twice let alone a .02% change over 45 minutes.

 

[Angrymongoose]

Its a 10% change? How did you get 2%?

 

[Ta2dResqr]

Its a 10% change? How did you get 2%?

you said 1.12 moved to 1.14. If you are repeating the numbers in the screen, LTFT is reported as a %. 1.12 = 1.12% not 1.12x map desired. So an increase to 1.14 would be a .02% not even 2% let alone 10%. Even 1.1 to 1.2 is only .1%. According to Ford, the concern becomes when your LTFT is greater than 25% (either direction) or your STFT is greater than 5% or less than 10%. Your numbers are showing ~1% and look great. Are you having any other issues or are you just going off these numbers and assuming there must be an issue?

 

[Ta2dResqr]

Fuel Trim

Short Term Fuel Trim
If the oxygen sensors are warmed up and the PCM determines the engine can operate near the 14.7 to 1 for gasoline stoichiometric air to fuel ratio, the PCM enters closed loop fuel control mode. Since an oxygen sensor can only indicate rich or lean, the fuel control strategy continuously adjusts the desired air to fuel ratio between rich and lean causing the oxygen sensor to switch around the stoichiometric point. If the time between rich and lean switches is the same, then the system is actually operating at stoichiometric. The desired air to fuel control parameter is called short term fuel trim (SHRTFT1 and SHRTFT2) where stoichiometric is represented by 0%. Richer (more fuel) is represented by a positive number and leaner (less fuel) is represented by a negative number. Normal operating range for short term fuel trim is between -25% and 25%. Some calibrations have time between switches and short term fuel trim excursions that are not equal. These unequal excursions run the system slightly lean or rich of stoichiometric. This practice is referred to as using bias. For example, the fuel system can be biased slightly rich during closed loop fuel to help reduce nitrogen oxides (NOx).
Values for SHRTFT1 and SHRTFT2 may change significantly on a scan tool as the engine is operated at different RPM and load points. This is because SHRTFT1 and SHRTFT2 react to fuel delivery variability that changes as a function of engine RPM and load. Short term fuel trim values are not retained after the engine is turned OFF.

Long Term Fuel Trim
While the engine is operating in closed loop fuel control, the short term fuel trim corrections are learned by the PCM as long term fuel trim (LONGFT1 and LONGFT2) corrections. These corrections are stored in the keep alive memory (KAM) fuel trim tables. Fuel trim tables are based on engine speed and load and by bank for engines with 2 heated oxygen sensors (HO2S) forward of the catalyst. Learning the corrections in KAM improves both open loop and closed loop air fuel ratio control. Advantages include:

- Short term fuel trim does not have to generate new corrections each time the engine goes into closed loop.
- Long term fuel trim corrections can be used while in open loop and closed loop modes.
Long term fuel trim is represented as a percentage, similar to the short term fuel trim, however it is not a single parameter. A separate long term fuel trim value is used for each RPM and load point of engine operation. Long term fuel trim corrections may change depending on the operating conditions of the engine (RPM and load), ambient air temperature, and fuel quality (% alcohol, oxygenates). When viewing the LONGFT1 and LONGFT2 PIDs, the values may change a great deal as the engine is operated at different RPM and load points. The LONGFT1 and LONGFT2 PID display the long term fuel trim correction currently being used at that RPM and load point.

 

[Angrymongoose]

This is monitored on livewire. Every .01 is 1% given the way the config file/livewire is set up. So my ltft is rose all the way to 22% on just bank 1 on the drive. I am fairly certain it would have made it to 25% had the drive been any longer.

 

[Ta2dResqr]

Long term fuel trim is represented as a percentage, similar to the short term fuel trim, however it is not a single parameter. A separate long term fuel trim value is used for each RPM and load point of engine operation. Long term fuel trim corrections may change depending on the operating conditions of the engine (RPM and load), ambient air temperature, and fuel quality (% alcohol, oxygenates). When viewing the LONGFT1 and LONGFT2 PIDs, the values may change a great deal as the engine is operated at different RPM and load points.

 

[Angrymongoose]

I get it, you have no idea.

 

[Bighead Super T]

Did you use New Stock injectors to replace old?
Did you log before previous problem = have something to directly compare too?

 

[Angrymongoose]

Yes they are new injectors. I did use bosch as motorcraft ones are just rebranded bosch ones. I suppose the quality control may be different though and that could be my issue.

I did log and send in to gearhead back when I was getting the p219a. The ltft would peak at 25 to 26% at wot and it idled at 17% on bank 1 when that was happening. I dont think I have that log anymore though.

This time the issue is more at constant rpm the stft stays at 3% which forces the ltft to slowly keep climbing. It weirdly only happens after driving for a long time, say 30 to 45 minutes. Shorter drives around town usually get the ltft to adjust back down.

 

[stripSHO]

you said 1.12 moved to 1.14. If you are repeating the numbers in the screen, LTFT is reported as a %. 1.12 = 1.12% not 1.12x map desired. So an increase to 1.14 would be a .02% not even 2% let alone 10%. Even 1.1 to 1.2 is only .1%. According to Ford, the concern becomes when your LTFT is greater than 25% (either direction) or your STFT is greater than 5% or less than 10%. Your numbers are showing ~1% and look great. Are you having any other issues or are you just going off these numbers and assuming there must be an issue?

the fuel trim PIDs report as a ratio, meaning 1.00 = 100% (no error), 0.90 = 90% (-10% error), 1.14 = 114% (+14% error), etc. If we're going to be persnickety, lets also point out that the stated rise from 1.12 to 1.20 is a 67% increase in fuel error.

Yes they are new injectors. I did use bosch as motorcraft ones are just rebranded bosch ones. I suppose the quality control may be different though and that could be my issue.

I did log and send in to gearhead back when I was getting the p219a. The ltft would peak at 25 to 26% at wot and it idled at 17% on bank 1 when that was happening. I dont think I have that log anymore though.

This time the issue is more at constant rpm the stft stays at 3% which forces the ltft to slowly keep climbing. It weirdly only happens after driving for a long time, say 30 to 45 minutes. Shorter drives around town usually get the ltft to adjust back down.

It's hard to say much without a comprehensive log. Maybe an injector is clogged. Maybe an o2 sensor is on its way out. Maybe there's an exhaust leak. Maybe you've got a bad valve. Maybe there's some combustion issue that is pumping unburned air into the exhaust. But if the STFT is truly stuck at a constant 1.03 then that seems like a sensor problem to me. Did you check for any pending codes?

 

[Angrymongoose]

Alright took it out today and its not pulling fuel on the short drives like it had before.

I have a p2096 and p219a pending as of today, just like when the injectors went kaput earlier this year. I assume the bosch injectors came back to bite me in the ass. I ordered a set of motorcraft ones already and Ill put those in when they get here. Fortunately the second time around should be a lot faster and easier.

 

[stripSHO]

Alright took it out today and its not pulling fuel on the short drives like it had before.

I have a p2096 and p219a pending as of today, just like when the injectors went kaput earlier this year. I assume the bosch injectors came back to bite me in the ass. I ordered a set of motorcraft ones already and Ill put those in when they get here. Fortunately the second time around should be a lot faster and easier.

I dunno, odds seem pretty slim of another, new, injector crapping out so soon. But if it's true then I would probably look over the fuel system to find a reason they're plugging up.

 

[Angrymongoose]

I agree it seems odd, and if it was motorcraft ones Id put in I would be inclined to look elsewhere. However its fairly common that bosch parts turn out to be duds. I took a gamble on them and it didnt pay off.

Im also not interested in playing wild goose chase to see whats wrong. Basically if this doesnt fix it, Im pulling off all the parts Ive put on and selling this fickle bitch.

I dont have any vacuum leaks, it cant be a fuel filter or pump as it only affects one bank, the pcv system is working properly, about the only other option that isnt injectors is an exhaust leak. The exhaust leak would have to be insanely small. I cant find anywhere thats leaking.

 

[SeanDev]

I agree it seems odd, and if it was motorcraft ones Id put in I would be inclined to look elsewhere. However its fairly common that bosch parts turn out to be duds. I took a gamble on them and it didnt pay off.

Im also not interested in playing wild goose chase to see whats wrong. Basically if this doesnt fix it, Im pulling off all the parts Ive put on and selling this fickle bitch.

I dont have any vacuum leaks, it cant be a fuel filter or pump as it only affects one bank, the pcv system is working properly, about the only other option that isnt injectors is an exhaust leak. The exhaust leak would have to be insanely small. I cant find anywhere thats leaking.

Same thing happening to me, leaky injector caused ones bank to go rich and other bank to run lean.

 

[Angrymongoose]

I suppose I could report that replacing the bosch with motorcraft injectors paid off. As an added bonus I've become much faster at pulling the intake and swapping injectors, so yay for that.

I do have still have a slight issue with extended idle time, especially in the cold, causing the long term fuel trims to climb a bit, but it brings itself back down after driving for a bit. I've been told that my current animal free down pipes and the associated devices to keep the codes from popping up could be a part of that problem, given that the downstream O2s will never actually read what they want to see. I'd love to grab a proper set from ppe but that's a lot of money to throw at a minor inconvenience.

 

[SeanDev]

I suppose I could report that replacing the bosch with motorcraft injectors paid off. As an added bonus I've become much faster at pulling the intake and swapping injectors, so yay for that.

I do have still have a slight issue with extended idle time, especially in the cold, causing the long term fuel trims to climb a bit, but it brings itself back down after driving for a bit. I've been told that my current animal free down pipes and the associated devices to keep the codes from popping up could be a part of that problem, given that the downstream O2s will never actually read what they want to see. I'd love to grab a proper set from ppe but that's a lot of money to throw at a minor inconvenience.

I wouldn't even want to look at what PPE costs now.,,,, I just did, dang that's $500 more than what I paid just a year ago for catted. I went with catted just because tuner recommended, some for the reasons your stating and other reason is so he wouldn't have the EPA knocking on his door. And gambling with Bosch injectors myself, 40 bucks each vs 200 each for motorcraft. But from what I've read they all come out of the same plant.

 

[SeanDev]

Is this extended idle time using remote start or happening with you in the car and starting it? Have you ever drained capacitors, and let it do a idle relearn? Best car sits for 10 to 15 minutes idling while relearning after a reset.

 

[SHOdded]

Alright took it out today and its not pulling fuel on the short drives like it had before.

I have a p2096 and p219a pending as of today, just like when the injectors went kaput earlier this year. I assume the bosch injectors came back to bite me in the ass. I ordered a set of motorcraft ones already and Ill put those in when they get here. Fortunately the second time around should be a lot faster and easier.

seems new injector fixed the p219a code for him

I give up, need an assist!

So I've been chasing a kr problem for over a week now, I've done everything from replacing coils to rechecking all of my intake piping, I even sleeved the lock sensor wire just in case. But under WOT only i hear an audible ticking noise and kr goes +4-5. Running out of ideas, I did have a bad...

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