Return style fuel system problems

[TW1NTRB0]

I have a Fore stage 4 return style fuel system with dual TI Auto 267 pumps, 5psi hobbs switch, hooked up to an FC3 controller. The problem I have been fighting is anytime you get into boost with more than say 50% throttle input the car has a very big bog or hesitation to it and then it takes off and runs through the rpm range fine. Very similar to when you launch with too little rpm at the track and the car bogs except mine does it with the car in motion. The car runs and drives fine with normal driving. It may stall 1 out of 50 stop lights but that can be fixed in the tune. The idle is high but idle quality is fine, just bounces every once in a while.

The Hobbs switch and both pumps are wired to the FC3 controller. Pump 1 is tapped into the large yellow with grey stripe wire on the FPDM harness. The FC3 gets power from the battery and has a 100 amp fuse in between. The Hobbs has 1 wire going to remote pump 1 and the other wire going to remote pump 2+3 on the controller. The FPDM tapped wire is going to remote pump 1. Then there is a ground and pump 1 is wired to pump 1 +- and pump 2 is wired to pump 2 +-. The only thing I saw that jumped out to me and it may not matter but the Hobbs switch is tapped into the intake pipe just before the throttle body. Fore says this needs to be under vacuum and boost, should I move this to a vacuum block?

The car feels like the second pump is turning on with a delay but that shouldn't matter right? I mean I'm only seeing 7.4lbs of boost right now so the first pump should be able to handle that easy. Or am I misunderstanding how it works and the two pumps share load when the other activates? Myself and my tuner are scratching our heads as he says he has it setup correctly for a return style fuel system. The tuner is focused on the ID1300's as the issue but once the car gets rolling the bog goes away after the first time it does it or at least I'm not noticing it. We have tried injector data for 40psi and 58psi while setting rail pressure with the vacuum port disconnected with KOEO. At first I was thinking with 40psi there was too much pressure drop and the injectors could not supply enough fuel on the initial hit but now I think it is pumps related as going to 58psi made very little change. At 58psi the bog was there but slightly less noticeable. The entire fuel system has been taken apart and checked and both pumps were bench tested as working, any thoughts?

Rundown of the car....
MPS 1500 built motor featuring a sleeved block and the sleeves are pinned to prevent walking. Top and bottom jackets have block struts welded in the jackets to prevent cracking. Manley I-Beams and forged pistons, TSS gears, stock heads and cams with MPS spec valve springs and a valve job. Armageddon twin turbo kit, Fore stage 4 parallel dual pump return style fuel system with a hobbs switch and FC3 controller (100 amp fuse), ID1300 injectors, and a whole bunch of other shit that's not important.

 

[TW1NTRB0]

Also we are tuning on 93 pump, we have not done any E85 tuning until we get this issue worked out.

 

[REDS197]

Try grounding the second pump to run full time and see what the results are.

 

[TW1NTRB0]

Going to try that tomorrow, weather took a turn and the rain is too heavy to try today. I'll bypass the hobbs with a jumper wire and if it's not the hobbs and still does it with both pumps full time then I'll try each pump as a single by disconnecting the other and go from there. I may need to send the whole unit into Fore for testing.

 

[CoreGT]

The changes in the tune for a return system not seeing boost reference is basically disabling one item, that's it.

You say the car bogs, but what do the logs show? Does the fueling go rich/lean, is the throttle closing?

Tune for 58 PSI, run without boost reference right now for testing, make sure the regulator is set to 58. In the tune, make sure that you account for the pressure loss at RPM as a result of boost.

 

[TW1NTRB0]

I'd like to get out there and get a log but the weather sucks right now. Any specific PID's I need to look at? I set the fuel pressure with the key on engine on and the vacuum hose pulled from the regulator which is the way Fore advised to set it as the pump only primes and bleeds down rather than the pumps running full time with just the key on. I disabled the hobbs switch by bypassing it this morning and the car was stumbling when transitioning to >50% throttle. This was only a general test after a morning run to the store. I went out and disabled pump 1 and moved pump 2 over to the pump 1location and will test to see if pump 2 runs fine by itself. If that's the case the pump 1 must be bad. If not I'll try the opposite and prove out the second pump. I can log with my laptop once the weather clears but since the Copperhead doesn't report fuel pressure by OBD II what are my options for logging and what is a good list of PID's to log? Other than that I'll have to send the sending unit into Fore for flow testing and if that's fine then I'm really stumped.

I'm waiting on the original dyno file from my tuner since he had it on the dyno and said everything was good at that point. Too many revisions and things changing that my stft's are -20 to -30 on both banks and general a/f is around the 12's cruising so I think with all the band aiding going on with the tune I need to start back from the beginning. LTFT's for some reason aren't reporting on my Aeroforce gauges so I'll double check the Platform I set and just log them by laptop. The car is also maintaining it's a/f ratio when cruising off the throttle when normally it would shoot way up lean, 28.xx or so. Maybe that's fine I don't know but I'll get some logs once the weather clears.

 

[onebadgsx]

had same problems.... swapped tuners all went away. tooning issues....

 

[TW1NTRB0]

I think I may agree with you on this one onebadgsx. I don't know if I would switch tuners as I have faith but who did you use to resolve the problem? I would like to speak with them and talk about the problem.

I bypassed the hobbs switch and went out for a drive and the problem was still there. I then disconnected pump 2, took it for a drive with no change. I then did the opposite and ran only on pump 2 and you guessed it, same thing. I got the dyno file back from my tuner. Something that bothered me on all of the revisions is how the car was pulling maximum fuel (-28.9, both banks) and barely holding mid 12 a/f at idle and cruising. The car also does not go lean at 28.9 when your coasting in gear, it just maintains the commanded a/f. Also the bog or hesitation is not that bad but it's there usually only in the first gear that you accelerate from and then the subsequent gears don't do it. When I reloaded the dyno tune the a/f is spot on and it isn't compensating very much on the STFT's to keep the same commanded a/f. The problem is the bog or hesitation is now huge and does it in every gear whether you run through the rpm range or not. I wired the FC3 controller back up with pump 1 full time and pump 2 activated by the hobbs. I don't think it's the hobbs anyway as I'm not seeing 5psi when the problem occurs. Mechanical problems do not fix themselves and the tune changes are making the bog different so today I am going to take logs and send them to the tuner and go from there. My main concern was pinpointing the problem, tune vs mechanical so I'm not chasing my tail any more. My tuner was upfront and said he never tuned a setup like mine, mainly around the return style with ID1300's so I'll work with him further and see if we can figure this out.

 

[onebadgsx]

Daniel at TSS but he tunes only in person on his dyno. previous with 1 of the big 2 known tuners

 

[TW1NTRB0]

Cool thanks, I'll at least give him a call and see if he has some advise to share on the problem. He's a bit too far from me but who knows.

 

[TW1NTRB0]

I flew down to Tampa for the Stanley Cup Finals and haven't had much time since returning to datalog the car. I did have some time this morning and I've posted the log in case anyone wants to look at it. I sent the log to my tuner but replies can be slow depending on work load and I'm impatient

*EDIT*
I forgot to hook up the vacuum source to the regulator for the boost reference so I went back out and grabbed another log. The knock retard does not look as bad to me on this log but the hesitation or bog is there every time I go WOT. I removed the previous log since the regulator wasn't setup right.

Datalog 1-2 - I ran this one from the beginning of starting the car until I returned home. I went WOT several times in 2nd, 3rd, & 4th gear and it hesitated or bogged each time equally.

Any thoughts?

 

[cb900f]

I flew down to Tampa for the Stanley Cup Finals and haven't had much time since returning to datalog the car. I did have some time this morning and I've posted the log in case anyone wants to look at it. I sent the log to my tuner but replies can be slow depending on work load and I'm impatient

*EDIT*
I forgot to hook up the vacuum source to the regulator for the boost reference so I went back out and grabbed another log. The knock retard does not look as bad to me on this log but the hesitation or bog is there every time I go WOT. I removed the previous log since the regulator wasn't setup right.

Datalog 1-2 - I ran this one from the beginning of starting the car until I returned home. I went WOT several times in 2nd, 3rd, & 4th gear and it hesitated or bogged each time equally.

Any thoughts?

At what RPM does the bog start/end? At the 32.5 sec mark, it looks like you went WOT @ 2500 rpms and the car did not go into a rich mode until 3300 rpms @ 33.5 sec mark. Is that the area you are describing?

 

[TW1NTRB0]

Yes that is roughly the area the bog was felt on the first pull. I haven't been able to nail it down to a specific rpm as it seems to do it above 2500 & 3500 rpm as well if that's where I go WOT. It just seems to happen anytime I press the gas pedal all the way to the floor and go WOT, the bog happens immediately once I push the pedal down all the way. When it bogs it does it for a second or so and then the car accelerates like normal so I don't think it picks up any rpm in the process. It seems to start and stop at the same rpm, as soon as I press the pedal all the way down the bog is instant every time.

Also I don't have my Windows machine with me right now, using a MAC at work. However once I get back home this evening I'll look back over the log as I went WOT 3 or 4 times in that datalog and it bogged each time the same but at different rpms. I also ran through a few shifts and each shift it did it in the upper rpm range. I'll see if the same event is happening during the shifts and higher rpm.

 

[cb900f]

Yes that is roughly the area the bog was felt on the first pull. I haven't been able to nail it down to a specific rpm as it seems to do it above 2500 & 3500 rpm as well if that's where I go WOT. It just seems to happen anytime I press the gas pedal all the way to the floor and go WOT, the bog happens immediately once I push the pedal down all the way. When it bogs it does it for a second or so and then the car accelerates like normal so I don't think it picks up any rpm in the process. It seems to start and stop at the same rpm, as soon as I press the pedal all the way down the bog is instant every time.

Also I don't have my Windows machine with me right now, using a MAC at work. However once I get back home this evening I'll look back over the log as I went WOT 3 or 4 times in that datalog and it bogged each time the same but at different rpms. I also ran through a few shifts and each shift it did it in the upper rpm range. I'll see if the same event is happening during the shifts and higher rpm.

I'm no tuner, nor do I play one on TV. But if I had to guess it sounds like the Fuel Enrichment Rate/Delay. There is also a Fuel Enrichment Pedal option that tells the car when to go into enrichment vs pedal position vs rpm.

Tuner can definitely help, have you sent them the logs?

NM, re-read your first post. Try a different tuner. :-(

 

[TW1NTRB0]

Thanks for at least looking the log over. Really just looking for anything to go on at this point. I've spoken with Armageddon Turbo, the shop that built the motor (MPS), and the tuner, and all have said they have never seen anything like it. I even had Dave the owner of Armageddon turbo send me his personal car (with a very similar setup) tune files and his tunes exhibited the same issue. I did send the logs to my tuner, just waiting to hear back. I'll also mention the things you noted above. My tuner did say upfront that he had not tuned a setup like this before so I'm still holding out and hoping we get it figured out. I've spoken to some other well known tuners and I'd have a hard time justifying $2K to tune a car on pump and E85, I mean I get it that this is not a stock car but really it's just a built motor with ID1300's, twin turbos, and a return style fuel system. I'd think it would be easier to tune than my stock motor twin turbo car.

 

[cb900f]

Thanks for at least looking the log over. Really just looking for anything to go on at this point. I've spoken with Armageddon Turbo, the shop that built the motor and the tuner and all have said they have never seen anything like it. I even had Dave the owner of Armageddon turbo send me his personal car (with a very similar setup) tune files and his tunes exhibited the same issue. I did send the logs to my tuner, just waiting to hear back. I'll also mention the things you noted above. My tuner did say upfront that he had not tuned a setup like this before so I'm still holding out and hoping we get it figured out. I've spoken to some other well known tuners and I'm not paying $2K to tune a car on pump and E85, I mean I get it that this is not a stock car but really it's just a built motor with ID1300's, twin turbos, and a return style fuel system. I'd think it would be easier to tune that my stock motor twin turbo car.

Did you use O2 extensions? Something doesn't add up. You were just cruising before doing a WOT here and the AFR wasn't at stoic. It also did a blip to stoic right as you went WOT.

Red line I added is stoic, grey highlighted line is actual AFR, brown line is RPMS, and blue line is Actual Throttle position.

 

[TW1NTRB0]

I removed the O2 extensions and went with Raptor sensors to rule that out as much as possible. I'm on my Mac now and can't see the whole log but the a/f may be off as I may have been coasting based on the a/f at 2.00 and then downshifted at that point so the blip may have been when I rev matched the shift, can't remember but on this particular tune the a/f on the Aeroforce gauges have looked pretty good by eye. One thing I have noticed though is my a/f is all over the place with all of the tune revisions I've seen. I had one tune where the a/f was in the high 11's to mid 12's at idle and cruising and the STFT's were maxed at -28.9 both banks and sometimes it would stop correcting and run in the 9's and die, only reloading the tune would fix it. I've since done away with all 20+ revisions and went back the the dyno tune file but I had the tuner edit it with the ID data set to 55psi as that is the rail pressure, before the tuner had it set to 40psi and that was the rail pressure but honestly it made no difference with how the car ran.

 

[cb900f]

I removed the O2 extensions and went with Raptor sensors to rule that out as much as possible. I'm on my Mac now and can't see the whole log but the a/f may be off as I may have downshifted at that point, can't remember but on this particular tune the a/f on the Aeroforce gauges have looked pretty good by eye. One thing I have noticed though is my a/f is all over the place with all of the tune revisions I've seen. I had one tune where the a/f was in the high 11's to mid 12's at idle and cruising and the STFT's were maxed at -28.9 both banks and sometime it would stop correcting and run in the 9's and die, only reloading the tune would fix it. I've since done away with all 20+ revisions and went back the the dyno tune file but I had the tuner edit it with the ID data set to 55psi as that is the rail pressure, before the tuner had it set to 40psi and that was the rail pressure but honestly it made no difference with how the car ran.

With these datalogs how much boost are you pushing? Can you try pushing around 7-10 psi and see how the tune handles it? Just thinking of other things to try.

 

[TW1NTRB0]

I'm seeing 7.5 - 8 psi with 5.5lbs spring at the gate and 20% on the eboost2. Plan is to put 10lb springs in it for pump and run 20 on E85.

I also went back and edited the bolded part from my last post shown below pertaining to the pre WOT a/f

I removed the O2 extensions and went with Raptor sensors to rule that out as much as possible. I'm on my Mac now and can't see the whole log but the a/f may be off as I may have been coasting based on the a/f at 2.00 and then downshifted at that point so the blip may have been when I rev matched the shift, can't remember but on this particular tune the a/f on the Aeroforce gauges have looked pretty good by eye. One thing I have noticed though is my a/f is all over the place with all of the tune revisions I've seen. I had one tune where the a/f was in the high 11's to mid 12's at idle and cruising and the STFT's were maxed at -28.9 both banks and sometimes it would stop correcting and run in the 9's and die, only reloading the tune would fix it. I've since done away with all 20+ revisions and went back the the dyno tune file but I had the tuner edit it with the ID data set to 55psi as that is the rail pressure, before the tuner had it set to 40psi and that was the rail pressure but honestly it made no difference with how the car ran.

 

[cb900f]

I'm seeing 7.5 - 8 psi with 5.5lbs spring at the gate and 20% on the eboost2. Plan is to put 10lb springs in it for pump and run 20 on E85.

I also went back and edited the bolded part from my last post shown below pertaining to the pre WOT a/f

I removed the O2 extensions and went with Raptor sensors to rule that out as much as possible. I'm on my Mac now and can't see the whole log but the a/f may be off as I may have been coasting based on the a/f at 2.00 and then downshifted at that point so the blip may have been when I rev matched the shift, can't remember but on this particular tune the a/f on the Aeroforce gauges have looked pretty good by eye. One thing I have noticed though is my a/f is all over the place with all of the tune revisions I've seen. I had one tune where the a/f was in the high 11's to mid 12's at idle and cruising and the STFT's were maxed at -28.9 both banks and sometimes it would stop correcting and run in the 9's and die, only reloading the tune would fix it. I've since done away with all 20+ revisions and went back the the dyno tune file but I had the tuner edit it with the ID data set to 55psi as that is the rail pressure, before the tuner had it set to 40psi and that was the rail pressure but honestly it made no difference with how the car ran.

If you blipped the throttle it would show on the blue line. The blue line is the actual throttle body angle. It's at the very top when the blip happens, which means it's at WOT and for some reason the car went lean for just a bit. at the 49.5 sec mark, I can see the blip and possible downshift.

From the 46.5 mark to the 51.5 mark the throttle (blue line) stays fairly constant (besides the downshift, where you can see the RPMS rise). But it is also very rich at that part when it should be running at stoic (10.0 for e85, or at the red line that I drew)