What choose for fule trim - OBD or PCM ?

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rustin
Posts: 5
Joined: Sat Apr 18, 2015 1:10 pm
Vehicle: Ford Mondeo MK3 2.0 PB 2002r

What choose for fule trim - OBD or PCM ?

Post by rustin » Thu Oct 22, 2015 11:44 am

Hello
I use forscana on the computer and android. I noticed something strange. If I choose fuel trim ( STFT and LTFT ) reading of the OBD are other than PCM.
OBD corrections are large and strange. The PCM is normal.
Why is there such a discrepancy? The difference is even 8%.
What choose for Mondeo 2.0 Duratec 2002?

FORScan
Site Admin
Posts: 2722
Joined: Fri Jun 13, 2014 2:21 am

Re: What choose for fule trim - OBD or PCM ?

Post by FORScan » Fri Oct 23, 2015 12:50 pm

This sounds like a bug.

Please save FSL with SFT/LFT for OBD and PCM (you will have to save 2 FSL, one for each module) and send to us (using PM or email address from Conact Us page of the site).

Also we need internal FORScan logs to see raw data returned by modules and find possible problem. Here is the instruction:

1. After the FSL files is saved, close FORScan.
2. WIndows Start button->All programms->FORScan->FORScan Log folder.
3. Folder with logs will be opened, you should see 2 files there: dump.bin and FORScan.log (may be more). Please zip them and email or PM

rustin
Posts: 5
Joined: Sat Apr 18, 2015 1:10 pm
Vehicle: Ford Mondeo MK3 2.0 PB 2002r

Re: What choose for fule trim - OBD or PCM ?

Post by rustin » Sat Oct 24, 2015 6:32 pm

Please tell me how to save logs by the use of cell phone program forscan lite.
As far as I know the same situation appear in all Mondeo MK3 Duratec 1.8 and 2.0

rustin
Posts: 5
Joined: Sat Apr 18, 2015 1:10 pm
Vehicle: Ford Mondeo MK3 2.0 PB 2002r

Re: What choose for fule trim - OBD or PCM ?

Post by rustin » Tue Oct 27, 2015 9:29 pm

Files sent to the PM

rustin
Posts: 5
Joined: Sat Apr 18, 2015 1:10 pm
Vehicle: Ford Mondeo MK3 2.0 PB 2002r

Re: What choose for fule trim - OBD or PCM ?

Post by rustin » Fri Oct 30, 2015 5:23 pm

It was done on a hot engine under the same conditions. On the pid of OBD correction of 14% and pcm 8% in the same conditions
Please go to the Forum Ford. There, people describe the same situation.

They are not the same parameters. Something is wrong. Even more so in the paid program should not be like that

FORScan
Site Admin
Posts: 2722
Joined: Fri Jun 13, 2014 2:21 am

Re: What choose for fule trim - OBD or PCM ?

Post by FORScan » Sun Nov 01, 2015 10:08 am

The problem is that we have checked it and see no bugs in either PCM or OBD calculations. Both PIDs are quite standard for Ford engines and their calculation formula is known and we have no reason to think they are wrong. We have no explanation for such a difference yet. The only idea we have is that when we implement a simultaneous output from several modules at once (so both PCM and OBDII PIDs can be displayed and recorded at once), we may get better understanding of what is going on.

In other words, we believe if someone tries to measure these parameters using a dealership scanner, s/he will get the same picture.

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