Injector time!!!!
FP duty cycle with BAP is high
- Thread starter fullboogie
- Start date
Van@RevanRacing
Active Member
What's the voltage out of the FPDM's? You'll need to remove the rear seat but I'd get a reading at the fuel hat. You might have an fuel pump down.
Good idea, Van. I'll check that this weekend, and log on Livelink as well. At least I had a gauge monitoring fp duty cycle, rather than finding out the hard way.
EDIT - just looked back over my prior three datalog sessions. FP duty cycle was between 89 and 91% at 6,200 rpm. Now I'm at 99% at 6,000, so something is definitely amiss.
EDIT - just looked back over my prior three datalog sessions. FP duty cycle was between 89 and 91% at 6,200 rpm. Now I'm at 99% at 6,000, so something is definitely amiss.
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Good idea, Van. I'll check that this weekend, and log on Livelink as well. At least I had a gauge monitoring fp duty cycle, rather than finding out the hard way.
EDIT - just looked back over my prior three datalog sessions. FP duty cycle was between 89 and 91% at 6,200 rpm. Now I'm at 99% at 6,000, so something is definitely amiss.
Fuel filter
You missed the very first post where I said it is brand new.
Here's a datalog from this morning - not good. Fuel pump duty cycle and injector duty cycle are pegged at only 5,300 rpm. And take a look at the fuel pump actual voltage - assuming it measures what I think it measures, I'm only getting 14 volts to the pumps instead of 17+ volts. Any ideas what's going on here???
Did you wire up the BAP to the front of the car? or did you tie it off so that it's always on?
Is the 14v an average of both circuts? Possibly the BAP is dying? Its very rare but possible. Silly thought but what is your altenator putting out? If its only charging at 10-11v rather than 14.5v maybe the BAP and FPDMs arent getting enough and the BAP can only put out 14v?
I posted that the voltage going to the FPDM's (from the BAP) is 17.2v at idle, so the BAP is fine. If you look at the datalog, battery voltage is over 14v, so that's fine too.
My mistake, totally forgot.
Is there a way to physically check what the pump is getting for voltage? Like unplug at the pump and check the volts? Kind of a weird problem, FPDM is all i can think of thats left. If you get good voltage there then im at a loss. Maybe compare fuel pressures with another member that has similar mods and see if there is a big difference (clogged filter, pump failing)? I'm just shooting in the dark here I dont have a lot of experience with newer fuel systems. Sorry i cant be more help.
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Even stranger - there is 14.2v going into each side of the BAP, 17.2v going out of each side and into each FPDM; 17.2v going out of each FPDM; and 17.2v on both sides at the fuel pump hat. And yet the Livelink datalog shows single digit fuel pump voltage for most of the log, and tops out at way less than 17v - which my multimeter says is wrong. How the hell can the datalog show single digit FP voltage at idle while I am simultaneously showing 17.2v on my multimeter??? WTF is going on?
Because live link may not be reading it right. Call sct and ask them.
Dude, I appreciate your enthusiasm - but you have no idea what you're talking about. Please stay out of this thread. I don't need your comments.
Just looking at the values, it looks to me like your hitting the upper range of the MAF and those fuel trims don't look right. You might want to hook up a wide band and see if it's not dumping a bunch of fuel in the engine causing your high duty cycles. You might try cleaning the MAF sensor. If they get dirty they can cause all sorts of errors.
Cat - thanks for the input. If I recall, the Ford MAF pegs at somewhere around 1050, correct? If that's the case, I think I will look into that as well - but I'll follow up on giving it a cleaning too. I do have a wideband, and it has always shown very rich WOT mixtures. I always figured it was the "safe" tune I was sold. And I agree, the STFT's don't look right either. I think I may have figured out the problem after discussing with one of the gurus on here, but it's going to take some time to get it investigated thoroughly. I'll keep you guys posted. And thanks for all the input.
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fullboogie - best of luck trying to find the answers to your questions. Wonder if someone with relatively the same setup as you could do the same tests and chime in on the results? I know every vehicle will be slightly different even if mods are the same but it could possibly help in one way or another?
Good Luck!
Ray
Good Luck!
Ray
Well, 1024 a/d counts is supposed to be the maximum counts for 5 volts, but Ford rarely sets anything at the maximum voltage range. There is a MAF transfer function in my SCT software for my 2012 and while there are two tables, one of which is the frequency based MAF my car uses, there is another table for a regular MAF and the max a/d range is set as 920, so you're at it if your MAF is calibrated the same way. You shouldn't be anywhere near that at 5,300 rpm, if I read your post right.
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Yeah, it's reading 919 on the log above at 5,384 rpm. MAF cleaning won't affect that, as a dirty MAF will tend to show less mass airflow that actual. I have no idea at this point if that's a separate problem, or part of what we discussed this morning as to what the root problem is.
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