Lean on GM Reflash? Fuel pump? Temp change? - Boost Forum

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Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 11:06 AM
Been noticing it doesnt jump to full rich lately and need some help. Did a pull today in first and second (its an auto)...in first gear afr is 12.4 then when it shifts to second it goes to 11.4. This started happening when it got warm out like 75-80 degree days. In the winter months when it was first put on 5-50 degrees out it would go straight to 10-10.5 any gear. Question is it the fuel pump going? Why would it get richer in second if it was?




Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 11:44 AM
Are you flooring it in first gear? We determined recently that unless you absolutely floor it the reflash won't dump fuel. If you're at something like 65% throttle and spinning the charger pretty good it still wont dump and it will try to make numbers like what you're describing. Under a few psi of boost its still trying to stay at 14.7. Scary, I know. Under full boost, 100% throttle situations it should be in the 10s though. If its not maybe it is something like your pump or fuel filter. How many miles on the body again?



"In Oldskool we trust"
Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 11:52 AM
Im pretty sure it was all the way down...it was to the carpet at least haha. Pretty sure its 71000 miles...the fuel filter was changed forgot when i did it though, and the fuel pump was changed at the dealer but it was still under warranty so that was even longer ago. Just weird that it started with the warmer weather and it gets richer in second and doesnt go leaner as the rpms rise...starts fine and so on (dont know what its like when a pump is dying) the first time the pump went out the car just shut off.



Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 12:03 PM
Yeah in my experience they either work or they don't. Although I will say that most replacement parts blow compared to the factory equipment and usually fail much faster. You run it low on fuel or anything? That can clog a filter instantly.



"In Oldskool we trust"
Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 12:27 PM
No i dont ever run it lower than 1/4 tank since this pump was installed...those numbers came on a full tank. In all though is 12.4 really that lean? I know 11.4 is what most are tuned at right?



Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 12:31 PM
Most tuners will say 12.4 is a hair away from the danger zone but when me and Philly logged our reflash info it seems like thats where the reflash likes to be unless your full out balls to the wall. If you are are full out balls to the wall and getting that number you definitely have a problem somewhere. First place to check is the wideband I'd think. How old is it and which brand?



"In Oldskool we trust"
Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 12:52 PM
Wideband is the AEM UEGO and its 2 years old.



Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 4:21 PM
Ill say ive been noticing the same thing on mine as well..

In second im getting 12.2 and in third itll drop down to 11.3..its just been in the last couple weeks. Ive got a racetronics im going to toss in just in case.
Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 4:41 PM
Strange...I dont think it'll make a difference but I'm going to change the fuel filter. It's in need of a change anyway.



Re: Lean on GM Reflash? Fuel pump? Temp change?
Wednesday, May 08, 2013 5:01 PM
Yah...im going to do mine as well one of these days.

Whats odd is my afr's tend to fluctuate. Some days ill get as low as 10.6.

Ill try and pay better attention to it over the next bit and see what its doing.
Re: Lean on GM Reflash? Fuel pump? Temp change?
Thursday, May 09, 2013 10:47 AM
Here are some vids...hard to kinda see since the wideband flashes on the camera but you can tell what it's doing.
Photobucket smashed to video for some reason

http://s1093.photobucket.com/user/rushbasher14/media/Pull2_zps87103a07.mp4.html

http://s1093.photobucket.com/user/rushbasher14/media/Pull1_zpsd69db321.mp4.html





Re: Lean on GM Reflash? Fuel pump? Temp change?
Thursday, May 09, 2013 11:00 AM
Just did a frame by frame here we go, AFR - boost
First pull
[IAT 123] 14.7 - 2 ; 14.4 - 5 ; 12.0 - 6.5 ; 11.3 - 8 (stayed there till let off) ; 11.7 ; 12.2 ; 12.4 ; 12.5 ; 12.1 (shifting here) ; 10.9 ; 10.1 ; 11.1 ; 11.3 ; 11.2 ; 11.3 ; 11.2 ; off throttle ; 10.0 ; 11.1 ; 10.8 ; 12.6 ; decel cut off [IAT 111]

Second pull (cant see boost or IAT)
14.6 ; 11.6 ; 11.5 ; 11.0 ; 12.1 ; 12.2 ; 12.3 ; 12.0 (shifting here) ; 11.8 ; 11.1 ; 11.0 ; 10.9 ; 11.0 ; off throttle ; 11.5 ; 10.0 ; 11.3 ; 17.0 ; decel cut off

How does the above all look? Wish Ryan or Oldskool could chip in here




Re: Lean on GM Reflash? Fuel pump? Temp change?
Thursday, May 09, 2013 3:23 PM
Luke C wrote:

Just did a frame by frame here we go, AFR - boost
First pull
[IAT 123] 14.7 - 2 ; 14.4 - 5 ; 12.0 - 6.5 ; 11.3 - 8 (stayed there till let off) ; 11.7 ; 12.2 ; 12.4 ; 12.5 ; 12.1 (shifting here) ; 10.9 ; 10.1 ; 11.1 ; 11.3 ; 11.2 ; 11.3 ; 11.2 ; off throttle ; 10.0 ; 11.1 ; 10.8 ; 12.6 ; decel cut off [IAT 111]

Second pull (cant see boost or IAT)
14.6 ; 11.6 ; 11.5 ; 11.0 ; 12.1 ; 12.2 ; 12.3 ; 12.0 (shifting here) ; 11.8 ; 11.1 ; 11.0 ; 10.9 ; 11.0 ; off throttle ; 11.5 ; 10.0 ; 11.3 ; 17.0 ; decel cut off

How does the above all look? Wish Ryan or Oldskool could chip in here


I just text Oldskool and asked him to chime in...






Re: Lean on GM Reflash? Fuel pump? Temp change?
Thursday, May 09, 2013 3:25 PM
Awesome, thanks dude



Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 4:58 AM
IMO, mid-12s are probably too lean for an M62 on any pulley. Even on more aggressive set ups, I usually suggest high 11's to 12.0 at the highest. As far as why it's doing what it's doing, on the GM reflash, it's really anyone's guess. I can tell you on 2.5bar fake cars I've tuned, a couple things can happen.

When the ambient temps get cooler, it usually goes a bit leaner, obviously because the air density changes, and once you warm it up, your IATs post blower will still be pretty warm. This is the downside to only having one IAT sensor on the car. The opposite is true when ambient temps warm up - less air density and the car has little to go on to recognize this, so it may be a tad richer. Cars designed for boost have an ambient and post IC sensor to properly meter fueling. It seems like you are having the opposite problem saying you're AFR gets leaner in higher ambient temps, but again, it's the GM reflash so who knows. If you are able to log knock retard, and see very little (<3*) to none, it's probably ok for now.






Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 6:21 AM
Ya i can see knock witht the aeroforce and i had zero through all the pulls. I have it set for the lights to flash if it goes over 3* and it never has.
I figured mid 12's would be too lean...I wonder why it's only in first in though. 11.0-11.3 seems perfect in second.
You think it has to do with the reflash having the tps % set too high to activate PE mode?



Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 6:27 AM
It's possible that the TPS engage setting is too high, but it would be the same in every gear, and the boost is throttle position dependent on the M62, so you should have the same airflow in every gear for a given throttle position, if that makes sense. Again, there is no table in HPT for fueling by gear, but if the reflash does something in the background on autos, all bets are off. I doubt it though.

how close to the head is your wideband located? If it's too far down stream, you may not be seeing the fuel because first gear is over so quick lol.

If you're not seeing any serious knock retard, I wouldn't worry too much about it, especially since it catches up in higher gears.



Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 6:41 AM
Ya that makes sense. I wonder if it would do something different for each gear since it's an auto...the part # for the tune is different but that could be just for the idle rpm
The wideband is right after the stock sensor on the pacesetter. Just weird that this just started when it got hotter out. When it was first put on every gear was 10-10.5 as soon as you hit it.
Ya there's no knock so that is one nice thing. Maybe I'll see what it does today since the weather is around 40 out ... Damn chicago weather haha



Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 10:39 AM
Seems to be the same regardless of IAT ... I did three pulls today and on one i got enough knock to set off the lights so it was over 3* I beleive the AFR was 12.5 when I saw the lights which is bull%$^& ... It seems if I get on the throttle quick enough to squeel/spin the tires it jumps to 10.9-11.1 in first and stays there but if you roll into it more slowly it'll do the numbers I posted. I'm %^&$*^& aggrevated. Nothing makes sense it's only in first, don't think it's the fuel pump since 2nd is good.



Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 12:06 PM
Luke CIt seems if I get on the throttle quick enough to squeel/spin the tires it jumps to 10.9-11.1 in first and stays there but if you roll into it more slowly it'll do the numbers I posted.[/quote wrote:


Not to be unhelpful but this is exactly what I noticed when I ran the reflash. Philly can chime in again but I'm fairly sure he was reporting the same thing. If you're knocking like that though, seems like something else is wrong.



"In Oldskool we trust"
Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 12:44 PM
When I get the chance, Ill see if I see the same thing since I am also an Auto with the reflash in a climate similar to yours.





Re: Lean on GM Reflash? Fuel pump? Temp change?
Friday, May 10, 2013 2:56 PM
Thats the first time i got knock since i put it on.
Sounds good...it'll be something to compare too.
Just changed the fuel filter since it was due and had some dirty looking liquid come out (slightly greyish) but doubt that would cause it. We'll see when I take it out again tomorrow



Re: Lean on GM Reflash? Fuel pump? Temp change?
Monday, May 13, 2013 10:28 AM
Small update...uplugged the battery to "reset" the computer to see if there is any difference and there is not. I noticed today that as the RPM's increased in whatever gear it got leaner and leaner so I guess it is time to replace the pump.



Re: Lean on GM Reflash? Fuel pump? Temp change?
Monday, May 13, 2013 11:48 AM
I have a fuel guage that we can hook up to your car and see where it is . Only thing is, I don't think we can monitor the guage and drive the car at the same time. It may not be long enough to snake it out of the hood, but i can look into that for you when I get home. I can always grab my hptuners from Jucnbst (Jeff) and log your car to see whats up.

Bryan





Save your money. It might be worth something someday.

Re: Lean on GM Reflash? Fuel pump? Temp change?
Monday, May 13, 2013 11:59 AM
Sounds good...I have a fuel gauge like the one you're talking about. I'll double check it when my dad gets home to tell if it goes up a bit with RPM's. Can you log with the reflash...I know it's locked, does that mean you just can't write but reading it is fine?



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