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vatman02
March 29th, 2008, 11:20 AM
I finally got a log of my problem, and I'm hoping someone can give me some help. Right now my car is running a bit rich, even more so on decel closed throttle. After driving for an hour or so it will run lean. On decel closed throttle it will go from 7:1 to 15:1, when it changes from rich to lean. The rpm, ect, iat, fuel pressure,and fuel flow are all the same when rich and lean. The only thing that my logs show as different is the map, when it's rich map is 42 kpa and when it's lean it drops to 37 kpa. I'ts not just the decel, it's through out the whole map, rpm range. Can the IAC motor be causing this? or do I have some freakish leak that comes and goes. Iv'e been fighting this for several months now, I thought at first it was my new injectors, so i've been chaseing my tail trying to get them dialed in. It did not do this prior to the injectors that I'm aware of. But the new injectors are nearly twice the size of the old ones so it is possible it was there and just less noticeable. I can post the log but you will need my calc.pid file to view the afr.
joecar
March 29th, 2008, 09:44 PM
Please post your log/tune files, someone will see something.
vatman02
March 30th, 2008, 04:06 AM
Something just dawned on me. At one point my injector duty cycle was over 240% and while discussing an issue I was having I was told the duty cycle is calculated from the VE table. So I lowed my whole VE table 10% and the duty cycle fell in line, below 100 % anyway. I believe I have had this probloem from the first day I started tuneing the car 2 years ago. I never was able to finish the Auto Ve process, every few months or I waould have to start over. I've checked for intake leaks with the car running and spraying wd40 around the intake, and didn't find a leak. I did find, last night that there was some timing being pulled from an EGR table B5907, because I have the EGR enabled for the fuel pressure sensor, but it was only 2 deg. I have to 2 notes in the log that contain a sample of the problem area. It starts at frame 20105, everything before that is just a bit rich. Thanx for the help.
vatman02
April 3rd, 2008, 12:52 PM
I see a few have looked at my tune. Does anyone have any input? I'm hoping this weekend to change out the IAC and see what I get. This issue just wont go away.

Edit: Could this be my problem? http://forum.efilive.com/showthread.php?t=5946&highlight=lean+cruise I have the speed enabler set at 256
joecar
April 4th, 2008, 03:41 AM
At this point it appears nobody saw anything...


Edit: Could this be my problem? http://forum.efilive.com/showthread.php?t=5946&highlight=lean+cruise I have the speed enabler set at 256
If you have a US PCM, then the lean cruise function would be disabled, so I don't think that link would apply;
Edit: In US you would do lean cruise using B3647 in COS3/COS5, see my edit at the end of this post.

Your problem may have something to do with your big injectors.


I'm hoping this weekend to change out the IAC and see what I get.
Try and see if it makes any difference.

Edit: more info -> showthread.php?t=7608 (http://forum.efilive.com/showthread.php?t=7608)
vatman02
April 4th, 2008, 12:29 PM
At this point it appears nobody saw anything...



Your problem may have something to do with your big injectors.



Edit: more info -> showthread.php?t=7608 (http://forum.efilive.com/showthread.php?t=7608)

Thats the strange thing Joecar the logged flow rate is the same and I see a difference in MAP 44 kpa then 37 kpa both at idle. Got roped into working this weekend not sure what I'll be able to do. I need emissions and my tags are now expired.