Im looking to put a resistor on my iat sensor Im thinking about starting with a 5.5k ohm resistor. Does anybody know the equvilant temperature for a 5.5k ohm resistor. I have a built 2.2 in my 1997 cavalier. It runs off of 110.
Explain to me why this is wrong. I really dont understand to much about tuning cars. Everybody at the track is telling me to put a resistor on the iat to give it more fuel.
More fuel DOES NOT = MORE POWER on fuel injected vehicles, and on most other vehicles. GM's from the factory normally run very rich.
Do you have a wide band to know what your air-fuel ratios even are? How do the "people" at the track know it needs more fuel?
Edited 1 time(s). Last edited Tuesday, September 27, 2011 10:37 AM
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
My car is running very lean. I do not know the air/fuel mixture no.
How do you know your car is running very lean?
Also the PCM only sees down to -26 degrees.
Also, you effectively turning of knock retard in the car.
For reference, 4.7k resistors on GMs normally read 55-60 degrees.
These are from another post...no one verified them.
Left Column Fake Temp, right column resistor value.
-40::: 77k-109k
-20 ::: 39k-53k
0 ::: 21k-27k
20 ::: 11k-15k
40 ::: 6.6k-8.4k
60 ;:: 3.9k-4.5k
80 ::: 2.4k-2.7k
100 ::: 1.5k-1.7k
120 ::: .98k-1.1k
140 ::: .65k-.73k
160 ::: .43k-.48k
180 ::: .30k-.33k
200 ::: .22k-.24k
220 .16k-.17k
248 .10k-.11k
284 .06k-.68k
Edited 1 time(s). Last edited Tuesday, September 27, 2011 10:53 AM
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
White plugs and exhaust tip. Just trying to increase fuel. It worked for me when i put a 4.7k resistor in. Just still was running a little bit lean. Just trying to figure out what 5.5k ohm resistor is gonna put my temp. The 4.7k ohm resistor put it at 56 degrees according to the scan tool.
But i dont have the scan tool anymore and need to get this fixed by thursday when i run.
I would be more worried about knock retard...or the lack of it.
With out a wide band your really just on a hope and a prayer, and even then its still a bad idea.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
Alright, thanks for your help. Im gonna look into getting a wideband o2s.
Do you know the best and easiest brand to go with the wideband?
If your plugs are white with the exhaust it's due to your 110 fuel containing lead.
SLO CAV (autocrossing dude) wrote:If your plugs are white with the exhaust it's due to your 110 fuel containing lead.
If you have leaded gas, you O2 sensors probably hate you, and might have failed already.
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
The resistor thing is a old saying. Our ECU's do not have any fueling based on IAT (at least not that we have access to). IAT is for sure used in spark retard.
Real tuning is the key.
FU Tuning
It won't help do anything but lighten your pocket, but I know the exact resistor your looking for. 9700 ohm equals out to 32F.
As someone that used to work in a dealer....
I used to make decent money "repairing" vehicles that idiots installed resistors in place of the IAT.
Have fun with the no gain in performance and possible negative side effects.
-MD- Enforcer wrote:SLO CAV (autocrossing dude) wrote:If your plugs are white with the exhaust it's due to your 110 fuel containing lead.
If you have leaded gas, you O2 sensors probably hate you, and might have failed already.
One tank every now and then or mix a few gallons every now and then with 93 it won't hurt but if you use it all the time then oh yeah they hate him lol.
It will increase fueling, I mean thats how a VE based tune works. It will also increase spark advance. If you are somehow flowing the air for it it will help. But even bolt ons are not enough to make the car run lean. You would need rockers and/or ported head and/or cam.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Guess I better be more specific in what I have. Its a race car, not a street car. It is a built 2.2. Flat top pistons, ground cam, custom valves, roller rockers, port and polished head, If I dont run 110 the car will run like crap. I burned the rings out of it when I ran regular 93. Just trying to add more fuel, looks like the only way to do it is put it on the dyno and tune it. I was just doing some research on the resistor. Looking for a cheap way out.
Yeah get it tuned. Make sure the dyno is a load varying dyno like a mustang or dyna pack.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
@!#$ these guys. put the resistor on. they're just gonna wish they were as smart as you.
Andrew Graham wrote:Guess I better be more specific in what I have. Its a race car, not a street car. It is a built 2.2. Flat top pistons, ground cam, custom valves, roller rockers, port and polished head, If I dont run 110 the car will run like crap. I burned the rings out of it when I ran regular 93. Just trying to add more fuel, looks like the only way to do it is put it on the dyno and tune it. I was just doing some research on the resistor. Looking for a cheap way out.
or you could get someone who HPtunes to tune your PCM so it will run the way you want to on 93 octane
