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car is runing very lean, need help.

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  #46  
Old 02-13-2007, 07:49 PM
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i have a dynojet and tested just about every single intake, a drop in KnN did better than EVERY intake we tested.


i am building a high compression motor right now and will be using the stock airbox.


as far as the thread starter, i havent seen any modded cars running that lean on the many many many VQs i have dynoed, i would bet a lot of money that his o2 sensor was placed in an improper place where it was seeing too much air..
 
  #47  
Old 02-13-2007, 07:50 PM
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Do u think im losing HP because of this or no?
The reason i think i am losing plenty of HP is that with no plenum and exhaust mod my car was not running lean at all and was puting down the same HP. But now it is running very lean and puts down the same HP, doesn't that mean that if u force more fuel to mix the amount of air that rushes in, it is going to put down more hp???
 
  #48  
Old 02-13-2007, 07:58 PM
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Originally Posted by Klubbheads
Do u think im losing HP because of this or no?
The reason i think i am losing plenty of HP is that with no plenum and exhaust mod my car was not running lean at all and was puting down the same HP. But now it is running very lean and puts down the same HP, doesn't that mean that if u force more fuel to mix the amount of air that rushes in, it is going to put down more hp???
When I put on an mrev+ and a stillen exhaust, I almost didn't see any gains at all. And at least one of those two mods are proven for gains.
 
  #49  
Old 02-13-2007, 08:08 PM
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Originally Posted by audiblemayhem
i have a dynojet and tested just about every single intake, a drop in KnN did better than EVERY intake we tested.


i am building a high compression motor right now and will be using the stock airbox.


as far as the thread starter, i havent seen any modded cars running that lean on the many many many VQs i have dynoed, i would bet a lot of money that his o2 sensor was placed in an improper place where it was seeing too much air..
I would agree 100%
 
  #50  
Old 02-13-2007, 08:21 PM
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I haven't been so confused on this forum.
 
  #51  
Old 02-13-2007, 08:31 PM
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Originally Posted by Klubbheads
I haven't been so confused on this forum.
Find out what the problem is first.
then get it fixed before you add new parts.
I'm sure its something simple.
 
  #52  
Old 02-13-2007, 08:55 PM
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Originally Posted by Klubbheads
I haven't been so confused on this forum.
If you have someone around you with a cipher or autoenginuity then you could monitor the wideband o2 sensors. I though I remember someone saying 2004 was the first year of the wideband for the G. you could get the o2 voltage and convert to get your a/f and see if the tailpipe sniffer is the cause of the apparent leaning.
 
  #53  
Old 02-14-2007, 10:18 AM
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Klubb,
Both Pasta and sloppymax have excellent suggestions. When I was having my (imaginary) a/f problems, I considered everything from leaks, fuel system problems(pump, filter, injectors), and possibly even bad sensors. In my case, it turned out to be poor operation of the sniffer on the dyno(how can you really mess that up?).

I tried to track down somebody locally that could log my widebands and fuel pressure, but couldn't ever track anybody down. Do you have an 04, or an 04.5? If you have an 04.5, then like sloppymax said, find somebody with an autogenuity or cipher to log your widebands.
 
  #54  
Old 02-14-2007, 10:27 AM
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I did some research on the emanage.
You need to add resistors to the coil pack wires when you put it in, this will solve the overtemp problem.

The emanage is by far the cheapest way to go, the UTEC is ~$800 with a good deal and you still need to find a good tuner. Then you have to try and mount it. It took UMS like 3-4 hours to get it mounted in twinsnails car, I did mine myself and it's a pain. The UTEC is overkill for an N/A car.
The Unichip is a little less and smaller but make sure the tuner can work with it as they are not as common. I have seen them for ~$500 used on here, new they are ~$700. The install is easy because they plug right in.
The emanage install should not be more than ~2hours plus the tune which most tuners are familiar with.
 
  #55  
Old 02-14-2007, 11:46 AM
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** The autoenginuity has a provision to read the newer G35 widebands.

Originally Posted by Jeff92se
Or look at what the O2 readings are doing via an OBDII data logger?
 
  #56  
Old 02-14-2007, 12:35 PM
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Originally Posted by trey.hutcheson
If you have an 04.5, then like sloppymax said, find somebody with an autogenuity or cipher to log your widebands.
Originally Posted by Jeff92se
** The autoenginuity has a provision to read the newer G35 widebands.
You're an hour and a half late.
 
  #57  
Old 02-14-2007, 12:43 PM
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*cough* https://g35driver.com/forums/showpos...5&postcount=12 *cough* hehe. No problem..

Originally Posted by trey.hutcheson
You're an hour and a half late.
 
  #58  
Old 02-15-2007, 01:00 AM
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A intake can make you run lean?

So if i got a popcharger and ztube

that could possibily make me run lean?
 
  #59  
Old 02-15-2007, 07:36 AM
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get a utec, i tune cars everyday, i get 14-20 hp all through the rpm range on every car i tune with it. the emanage sucks and just offsets factory timing, so the car will never run consistent NA. plus if you get one cheap, then you dont want to cut up factory wires, so you add the autosport harness and pay someone to wire it, you are at more cost than a utec.


its not over kill, its what most of these engines need. we actually time how long it takes for my customers to call after they leave and say "Holy ****, my car is sooooo much faster.

i can put a utec in a G in 10 minutes. its all about knowing what to do correctly. i will have the glove box shutting back all the way and the black cover on the bottom.


plus guys, lean is mean!!! you want the car to run as lean as possible with as much timing as possible before it knocks. (within reason)
 

Last edited by Audible Mayhem; 02-15-2007 at 07:39 AM.
  #60  
Old 02-15-2007, 10:11 AM
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I agree the utec is awesome but cheaper than a emanage for $150, autosport harness and install I highly doubt.
 


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