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Old 08-15-2005, 09:36 PM   #1
lowblow
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Default Stuck in closed loop fueling (i think)...need help!!!

So last week I got a protune and put down some nice numbers. After the dyno session we took it for a ride to make sure everything was fine on the street (and it was) and then I drove 5 miles to my GF's house. From there I drove 10 miles each way to dinner and then back to my GF's house. The car sat at her house for about three hours and then I left to go home.

This is where the problems began. I noticed a flat spot when I would come into boost and I looked up at my wideband and saw the AFRs climbing towards 17:1. I let off immediately and drove the rest of the way home sraying out of boost and maintaining a 14.7:1 AFR.

I was puzzled as to what had happened in 20 miles of driving so I tried to go to sleep, but that was difficult. I woke up this morning at 7:30 and gathered my AP, stock air box (thought maybe it was the intake) and headed back to the tuner staying out of boost the entire way. I got there around 9:15 and told him what was going on...out comes the laptop and we make a quick datalog and he sees the issue.

Apparently the ECU somehow switched itself back to the stock fuel map with the closed loop delays settings completely off the charts. Hill said that some of the values that were set at 120 the day before were now at 3000!!! He flashed my ECU again with the map from yesterday, but still no luck. We swapped MAF sensors with another car and we got the same results. We then waited till 10am est for Cobb to open up and he put a call into Christian. Christian then emailed Hill a new base map to start with, with updated dynamic advance numbers and we put the car back on the dyno. Hill had to recalibrate idle fuel trims because the front O2 sensor was sweeping back and forth causing the AFRs at idle to fluctuate between 14.4:1 to 16.9:1 :iono: He loaded the intake parameters from yesterday and started tuning again.

So 5 hours later on the dyno everything was looking like the final run from the cay before, so Hill reflash my ECu with the new map and we took it off the dyno. We went out on another road excursion and the AFRs weren't coming out of the 14s under load. Hill started the live tuning program and noticed that everything from the flash transfered over except for the fuel map. He loaded the fuel map to the ECU, but the problems persisted. He then started adding fuel across the board to see if the AFRs would change, but they wouldn't, so back to the shop we went to call Cobb again.

Hill checked a few more things that cobb mentioned, like the dataport connections and for an intake leak prior to the turbo, but we came up empty again. Cobb insisted that it had to be a leak, but nothing of the sort was found. So next we unmarried the AP from the car to determine if it was the AP causing the problem, or if something happened to the car during the 20 mile drive the night before.

Even with the stock ECU mapping we were getting the same problems. The AFR wouldn't come out the 14s, kinda like the ECU was stuck in closed loop. So after 7 hours at the tuner I left on the stock ECU program with basically a NA car because I couldn't get into boost.

We looked all over the engine bay trying to find the problem, but came up empty. What could've happened in 20 miles that would cause my car to run this way. It obviously isn't anything with the Cobb or the tune because it does it with the stock ECU programming

It makes absolutely no sense as to why it would run fine on the dyno and then go to crap as soon as we take it off

I am going to start with a vacuum leak check tomorrow by spraying starter fluid on parts of the intake track while the car is idling to see if the idle surges which would indicate a leak. Next, will be to check the front O2 sensor (anyone have one that I could borrow for a day or two?) to see if the wires are visibly destroyed. I might have to buy a new one After that I am at a loss as to what could be wrong. Hill has no idea, Cobb has no idea, and I have no idea. None of us have ever heard of something like this happening so randomly

BTW - This post in no way takes anything away from Hill and his tuning. He has stuck by his tune 100% and put lots of extra hours into it without thinking twice. I just wish I could find what is causing the problem so that I could enjoy the awesome tune I had for 25 miles

If anyone has ideas...PLEASE HELP ME OUT!!!

Update:

I have checked for a pre-turbo vacuum leak and have come up empty. I swapped front O2 sensors with a friend and also ECUs, but the same problem persists. Could it be a locked up injector? The fuel pump (walbro) is supplying fuel just fine as FP reaches ~61psi at full boost. I am really stumped so any help would be great.

Wednesday I am going to trace all wires in the car and try and find a frayed or broken one, but other than that, I don't know where to look.
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Old 08-15-2005, 09:52 PM   #2
hondaeater69
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whoa, that's some weird ass ****. I wish i could be of more help, i'll ponder it for a while but good luck in figuring it out, keep us posted when you do!
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Old 08-15-2005, 11:31 PM   #3
Rick Schu
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Before you start ripping the motor apart, I'd go back to the fact it doesn't sound like your ECU took the flash the first time correctly. I can't think of any way that after a full reflash, the ECU could revert back to the stock programming on any of the maps. Is this even possible? There is a learning function but its not that quick or extensive as you suggest. I'm guessing a bad ECU, assuming the tuner knows what they are doing.
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Old 08-15-2005, 11:53 PM   #4
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that's what i was thinking, but he said he switched ECU's and same thing. I would look into the wiring thing like you said, maybe some sort of short in the system or exposed wire hitting something. Was there ever any other sort of EM on your ECU before?
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Old 08-16-2005, 12:09 AM   #5
lowblow
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Yeah, I swapped ECU tonight with another 2004 and the same issues were present. I used to have the Utec and it ran fine, ever since I took that out, the problems have been there...it's been a week since then.
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Old 08-16-2005, 01:48 AM   #6
RiftsWRX
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Well... first things first... what EXACTLY is done to this car... secondly, this is an '04.. did you ever apply the '05 code to this AP? Did you ever revert it back to the '04 code before trying to Protune it? (assuming you had done the '05 stall fix in the first place)

Finally... check your fuel pressure regulator lines. Finally, if all else fails, it may well be a O2 sensor or injector. A fubar'd injector would be indicated by a very weird idle and fluctuations in the short term fuel trim.

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Old 08-16-2005, 07:33 AM   #7
lowblow
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Mods list...
Stromung Ceramic Coated DP, Invidia Catback, Crucial Uppipe, Crucial Cooling Package, Hyperflow TMIC, Perrin Intercooler Hoses, Perrin Short Ram, Walbro GS341 Fuel Pump, NGK Iridium One Step Colder Plugs

It never had the 05' software on it, but it does have the 1.30 version update on it now. The idle is fine, so I guess that rules out an injector.
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Old 08-16-2005, 09:25 AM   #8
x99percent
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- Check fuel pressure
- Datalog the injector duty cycle during a WOT attempt
- Re-check fuel pump install?

If the fuel pressure is dropping off at WOT, you might have a bad fuel pump or fuel pump controller.

If the duty cycle during a WOT attempt looks "normal" in comparison to a good WOT pull, then that helps to rule out the ECU/flash.
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Old 08-16-2005, 09:44 AM   #9
Rick Schu
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You need to log that car. If you have a laptop, use the free Tari logger.
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Old 08-16-2005, 09:52 AM   #10
Rick Schu
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I would go back and do the 2004 AP update, step by step, even if you've done it before:

http://www.accessecu.com/support/MY04_WRX_update.pdf

Of course, back up your protuner file first.

Apparently enough people are screwing up their APs with this issue that Cobb is recommending sending them in. Anyway, your tuner says that only the fuel maps didn't change? He's actually looking at the values on the maps or is this from data logging your car? If it was a wiring issue, I would imagine it would affect the entire reflash, not just one portion of it. Really sounds like an AP issue to me.
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Old 08-16-2005, 10:45 AM   #11
lowblow
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I will log the car tomorrow with the Tari logger.

Quote:
He's actually looking at the values on the maps or is this from data logging your car?
He is actually looking at what was on the ECU and the fuel map did not transfer. When he tried to make live tuning adjsutments to the fuel values nothing changed with the AFRs.
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Old 08-16-2005, 10:49 AM   #12
hondaeater69
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make sure the diagport cable is ok. If it's not transferring the data, and it doesn't work on another ECU, check the cable. Also maybe try to flash a different map with a different AP, maybe the AP is toast?
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Old 08-16-2005, 03:28 PM   #13
RiftsWRX
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I had a guy with a STI and an SR40 this weekend, tell me about how his first walbro did similar things. He swapped to a new one and it was fine... so I'd go back and verify the pump install, because it DOES sound like a fuel delivery issue.

Jorge (RiftsWRX)
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Old 08-16-2005, 03:30 PM   #14
Sublime5260
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Quote:
Originally Posted by lowblow
I will log the car tomorrow with the Tari logger.



He is actually looking at what was on the ECU and the fuel map did not transfer. When he tried to make live tuning adjsutments to the fuel values nothing changed with the AFRs.

by the way...did you ever get your **** back from berzerkled?
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Old 08-16-2005, 04:10 PM   #15
lowblow
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Quote:
Originally Posted by RiftsWRX
I had a guy with a STI and an SR40 this weekend, tell me about how his first walbro did similar things. He swapped to a new one and it was fine... so I'd go back and verify the pump install, because it DOES sound like a fuel delivery issue.

Jorge (RiftsWRX)
www.ProjectWRX.com
I'll check that tomorrow, and no Sublime, I never got jack ish from berzerkled
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Old 08-16-2005, 08:35 PM   #16
Sublime5260
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Quote:
Originally Posted by lowblow
I'll check that tomorrow, and no Sublime, I never got jack ish from berzerkled
what a prick
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