Can HP Tuner helps for flex fuel Ford truck problem?
Hello everybody. Recently a customer came in my shop to check an engine problem. This truck is very difficult to start when cold. Of course, no DTC in the PCM. After the routine checks, fuel pressure, fuel sample (less than 3%), vacuum leak, temperature, accuracy of oxygen and air flow sensors, I noted that the Flex Fuel Inferred (FFINF) calculation was wrong. The calculation was at 62%. I know this calculation should not exceed 12-15%. With the exception of hard start , the truck is performing very well on the road. I was wondering if the HP Tuner software could help me, that is to cancel the option of calculating alcohol in gasoline, to set the percentage to 0 for the rest of the life of the truck . Has anyone of you ever used this software to make this change? Thanks in advance for your answers
Fix the reason why the flex fuel content is off. MAF? Find what is causing it to be off and you will fix your problem. No need for a tune.
If this is a flex fueled vehicle it is designed to run on regular gasoline all the way up to E85. If it is reading 60% it is a valid reading you likely have a bad sensors or a faulty maf. what are your fuel trims? What is the baro reading in data. I would also look at all your temp sensors and fuel pressure at KOEO before attempting the cold start. After sitting overnight all your temp sensors…
I just ran into this issue with a 2011 E350 and the MAF was at fault. Once replaced fuel trims will go way negative until flex fuel % goes down to near 0 and then will level out. During my diag nothing really stood out other than flex fuel was way high and hard first cold start with the smell of fuel, I hope that helps.
Hello Daniel, You can stick the inferred ff with hptuners, but the root cause would still remain. Most systems make the Efuel inference during cruise conditions from my experience. In base fuel calculation they run lean, if the program cannot determine a system fault it infers that it "must" be running Efuel and adjusts the A/F ratio to dump more fuel to compensate. I believe you will fix the…
Thanks Bill. The truck will be in my shop tomorrow and I will look closely for a lean condition with a road test I will post later the result of the fix. Thanks in advance.
You're welcome. I have seen multiple issues across multiple brands calculate the E content incorrectly high. In all cases what causes it is a lean cruise condition. Once that is corrected it will no longer infer incorrectly. Just my experience. If this is the 2 speed pump with low pressure at low speed that turns into a real fun one to try and keep it in the range where it leans out.
Hell Bill. The truck is in my shop today. Baro sensor indicate 90 kpa, seems OK to me. It's a 2 speed fuel pump system with a returnless system without fuel pressure sensor. With the scan tool , I got 54 psi of pressure when I command the fuel pump. On the road, the fuel pressure vary from 35 to 40 to 54 psi maximum. It's a duty cycle system who runs only in 3 level of pressure. This morning …
Thanks Daniel, Reset your KAM. Test drive down the road at highway speeds and monitor fuel trim with a fuel pressure gauge somewhere in sight. Make sure ethanol resets. (Inferred flex fuel) Record your fuel trims (LT+ST) when your pump is in low speed operation. Especially under light load climbing a hill just prior to high speed pump engagement. Keep me in the loop when you have it cased.
Hello Daniel, Making any forward progress with this one?
Hello Bill. After several tests, we are supposed to replace the fuel pump. The truck is supposed to be in my shop next Tuesday. I will let you know the conclusion of this case. Best regards.
Thanks Daniel, Those 2 speed pumps can cause some interesting issues when they start to get weak.
Hello Bill. Finally we replaced the fuel pump module as planned. Also we reset the KAM . Then a fuel pressure gauge was installed to monitor the pressure during the test drive. After about 15 minutes, the fuel pressure had never dropped below 54 psi / po2, unlike the first test where the pressure had dropped to 40 and even 35 psi several times. After a few kilometers, the Flex Fuel Inferred…
motorcraftservice.com/freeresources… Daniel check this website and open the 2013 manual, page 62 describes the operation of the inferred flex fuel calculation and determination. A battery disconnect or KAM reset should bring the inferred value back to normal.
Thanks for the information Craig.
Ditch the thought of using the tuner to fix the problem. As others have said, "fix the problem" the correct way. Any time I run into a problem like this, I always capture fuel control data on a FRTD, then analyze the problems. I would imagine the fuel trims on this rig are all wacky. Since this vehicle uses MAF data, and oxygen sensor data, your FRTD will show problems with these sensors. Once…
I've seen this with E350s before, id reset the Kam and then go through a drive cycle until the data starts to make sense then monitor over time. The few that I've done never came back with the issue. Here in Canada we don't have E85 so its kind of rare to see flex fuel issues but the ones I deal with idle a lot and a couple of times I noticed the plugs were done for as well.