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I had the truck running with no problems then I went into enrichment rate and changed it from .0500 to 1.000. Also changed eq ratio vs rpm and now im getting a lean code. I have tried to lowering the enrichment rate a little at a time but still get the CEL. I love the way the truck runs just need to take care of that dam CEL.
Any help
The codes have nothing to do with enrichment rate or PE EQ ratio VS RPM). The airflow table (MAF) is not tuned and the PCM is having to add a bunch of fuel. Your LTFTs are maxing out and thus it throws the codes that you are lean. What are your mods and what have you done to tune it?
You're not commanding PE until 87% throttle?
Thats another thing that i have noticed but was going to handle this first. My throttle does not get more that 84%!Quote:
Originally Posted by 5_Liter_Eater
Truck is stock, has a magnaflow muffler and thats it.
I copied high octane to low octane
and just the PE other than TQ management.
I got the CEL with those codes after I changed the PE, so i figured thats why i was getting the codes. And no i have not messed with MAF, i was instructed not to mess with it because my truck is basically stock!
I'm surprised that the LTFTs are so far off with almost zero mods. Could point to a vacuum leak. Try resetting the fuel trims via VCM Controls.
I gaurantee the codes are not from the PE changes. I don't think you ever entered PE in that log because the PE Enable Hot TPS is 87%. Did anyone tune it before you?
You are fly by wire TB right? You should be logging ETC position rather than TPS position.
I would download a stock tune for your vehicle from the repository and compare it to yours. Change everything back to stock. Then begin tuning the MAF table. You can't just change the PE and assume you're achieving what you're commanding. You have to tune it, with a wide band. You can't reliably tune open loop/PE without one.
Well just read up on the 84% throttle deal. Im going to do some more checking on the PE enable throttle position.
Nobody has touched but me, i did send my file to a guy that does tuning here in Houston and he looked it and advised me to make those changes to PE, never mentioned anything about MAF. Im learning and was just looking for advice on what else i could do to make my tune better.Quote:
Originally Posted by 5_Liter_Eater
I still have my stock tune saved so ill start from there. I do have a wide band but its home and im working out in Louisiana for about a week
I guess the truck tune has the PE enable TPS set that high from the factory then. If you want to make changes to your PE I would look at lowering that, especially in the upper RPM's. Look at some car tunes to see how it's set.
The 84% TPS thing is normal.
As I said I don't know what would be driving the fuel trims up that high on an otherwise stock truck besides unmetered air. If that is not the case you can tune the MAF table in the non-PE areas with fuel trims. You could also just multiple the MAF table by .75 which will reduce it 25% and see where that puts your fuel trims at.
Thanks Bill!
Ill try the MAF first and see what happens. If it does not help ill go back to stock and start over.
Don't set your PE values to "0", remember that you're dealing with a computer and some times the zero value makes unpredictable results in the internal calculations. Better try these values that I often use in my calibrations:
Map: 30
Map Hyst: 3
Delay RPM: 1000
Enable RPM: 100
RPM hyst: 15
PE Enable TPS table:
Labels 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000
Enable TPS 78.0 74.3 70.5 66.8 63.0 59.2 55.5 51.8 48.0 41.1 32.5 20.7 20.7 20.7 20.7 20.7 20.7
It seems that someone touched the transmission but not the engine except for what you changed.
Makes sense! Computers are unpredictable
I see what you are doing with the PE Enable TPS. I understand but cant really put it in words. LOL
I guess yo want PE enabled earlier if you are higher in the RPM.
Well i did the trans stuff also but figured it had nothing to do with my CEL
Thanks
put the stock tune back in it.. you have a vacuum leak.
Really??
Only reason the hood has been open is for oil changes at the dealer and oil checks by me at the house. I already put the stock tune back on and will take a scan of it see what we see!!!
I would look for vacuum leaks as well. You could have been close to turning on the engine light before the last adjustment and it just so happen to come on after the last tune. It has to be something common to both banks of the engine. Vacuum leaks after the MAF, a dirty MAF sensor, bad tune are a few things that will do this. Typical problems I see are a dirty MAF and PCV lines disconnected. There is one downstream of the MAF sensor that goes to the valve cover, and one that pulls off the drivers side cover to the center of the intake manifold.
Well I put the stock tune back on and drove the truck for about 40 mikes in stop And go traffic and hwy driving. No CEL. turned truck off at gas station and turned it back on. No CEL. drove another 15 miles or so to where I was going and no CEL. When I saw the last post I got out of my truck and grabbed a flashlight and checked every possible vacuum port or hose as best I could and didn't see anything. I think it's just a bad tune. I will do some more reading and continue to figure things out. Now I know that rOute didn't quite work so on to the next.
Well I went back and started tuning on it from stock. I must have changed something in the other tune that i cant seem to find. I added all the changes to the new tune and drove the truck for about 10 miles and turn it on and off and no CEL!
Im finally understanding what affects what when i make changes and what to look for in on the scanner.
Thanks everybody for the help.
What do the fuel trims look like now?
Here is my last scan.
Can you post your stock file? I couldn't find one like yours in the repository.