Idle . .

[FeaRlezZ]

ok this question is specifically for full bolt on (including gt tb) GS guys. wut rpm's is ur idle at ?? mine is at 500rpm and sometimes slightly lower around 480 or 490 which seems to low to me

and if anyone knows wut the stock GS idle is set at please post as well

[joeyb]

I do not know for a GS, but mine (08 GT) is usually 640 - 700. which is what I usually hear people on here saying is about average for both models. I could be wrong tho, that is just my impression, memory on the subject

[FeaRlezZ]

ya i kno i can change it with the FIC but i would like to kno exactly y mine is low

[choppertwo]

Originally Posted by FeaRlezZ

ok this question is specifically for full bolt on (including gt tb) GS guys. wut rpm's is ur idle at ?? mine is at 500rpm and sometimes slightly lower around 480 or 490 which seems to low to me

and if anyone knows wut the stock GS idle is set at please post as well

mine has idled at 600 since I've had my car, even after my bolt ons- CHOP

[FeaRlezZ]

Originally Posted by choppertwo

mine has idled at 600 since I've had my car, even after my bolt ons- CHOP

do u have the GT throttle body ?? im wondering if it is the tps causing it but i forget back when i installed it if thats when my idle dropped

[muscles]

I'm right above 500. And I have everything bolt on minus a tune.

[FeaRlezZ]

it has not caused me any problems but it just feels low to the point that the car will stall (which i dont think it will)

[muscles]

Same here other wise someone would of posted about it . I don't see cause of concern for low idle for us.

[choppertwo]

Originally Posted by FeaRlezZ

do u have the GT throttle body ?? im wondering if it is the tps causing it but i forget back when i installed it if thats when my idle dropped

No, I don't have the GT TB, yet

[FeaRlezZ]

well if something happens then i will b the first to report it lol

[FeaRlezZ]

but it is interesting how my idle is at 500rpm and muscles is slightly over (we both have gt tb) and chopper is at 600rpm

[BPHILLY22]

My car idels at 500 or like u said 490 ... I have a gt with 39xxx... I've been wondering this also for awhile

[mikeeitup]

Mine at start up is around 1500 to 2000 for a minute but after driving seems to sit around 6-700.

[CrAnSwIcK]

Some lancer guys were having idle issues with the larger throttle body...My guess is that it would need to be adjusted or calibrated somehow. As the ECU does not know you've swapped throttle bodies.

[Steveo]

Mine is the same 500 400rpm(Proflow) sum times differs when I put my ac on..I was told because of the more air flow an other bolt ons..tune will help will find out sunday

[nokiauser]

I think it's 650 once the engine has warmed up fully.

[sham_rock1994]

my 07 gs is completely stock right now and it idles at 500 all the time. i was wondering if my car was messed up because of it being so low but from all u guys having the same problem i am guessing that is normal.

[Fizzix]

Does Mitsubishi use an IAC valve (Idle Air Control) to regulate the idle speed on these engines? I've replaced them on other cars and when they fail you typically get a very low idle speed, sometimes to the point that that engine will stall or won't be able to maintain a stable idle. They act like a controlled leak allowing air to bypass the throttle plate when it's closed.

[FeaRlezZ]

Thread Revive !

im wondering now if since i went from 2 1/4" piping to 2.5" with less backpressure caused the low idle. exhaust velocity im sure is lower at low rpm's and at idle. . . so mayb thats the reasoning for the idle being around 490 - 500

[pat_08GT_Spyder]

interesting theory...
my GT seems to idle lower as well since i opened up the exhaust... like fully warmed up she'll idle at 500 rpms, sometimes even a tad below that...

[Ballfade]

I sit at about 500, ill check for ya when i drive later.

[FeaRlezZ]

is there a way to re-gain the slight loss in low end torque due to decreased exhaust velocity at low rpm's ?? i have been doing some research on backpressure and exhaust velocity and this 1 paragraph alone was very interesting to me ->

"This last concept is why low velocity gas flow and backpressure hurt power production. Understand that during the exhaust stroke of a 4 stroke engine, it's not only important to get as much of the spent air/fuel mixture out of the chamber (to make room for the unburnt mixture in the intake system), it's also important that these exhaust gasses never turn around and start flowing back into the cylinder. Why would this happen? Because of valve overlap, that's why. At the end of the exhaust stroke, not only does the piston start moving back down the bore to ingest the fresh mixture, but the intake valve also opens to expose the fresh air charge to this event. In modern automotive 4 stroke engines valve overlap occurs at all RPM, so for a short period of time the exhaust system is open to these low pressure influences which can suck things back towards the cylinder. if the exhaust gas velocity is low and pressure is high in the system, this will make everything turn around and go the opposite direction it's supposed to. If these gasses reach the cylinder they will dilute the incoming mixture with unburnable gasses and take up valuable space within the combustion chamber, thus lowering power output (and potentially pushing the intake charge temp beyond the fuel’s knock resistance). So having good velocity and therefore low pressure in the system is absolutely imperative to good power production at any RPM, you just have to remember that these concepts are also dependent on total flow volume. The overall volume of flow is important because it is entirely possible to have both high velocity and high pressure in the system, if there is simply not enough exhaust piping to handle the needed airflow."

in regards to that comment^, is it possible to re-gain exhaust velocity at low rpm's and idle by adding more fuel to the mixture ?? or does it not work like that ? or does this have to do with timing more than air/fuel ?

[NitroGlisson]

Originally Posted by FeaRlezZ

is there a way to re-gain the slight loss in low end torque due to decreased exhaust velocity at low rpm's ?? i have been doing some research on backpressure and exhaust velocity and this 1 paragraph alone was very interesting to me ->

"This last concept is why low velocity gas flow and backpressure hurt power production. Understand that during the exhaust stroke of a 4 stroke engine, it's not only important to get as much of the spent air/fuel mixture out of the chamber (to make room for the unburnt mixture in the intake system), it's also important that these exhaust gasses never turn around and start flowing back into the cylinder. Why would this happen? Because of valve overlap, that's why. At the end of the exhaust stroke, not only does the piston start moving back down the bore to ingest the fresh mixture, but the intake valve also opens to expose the fresh air charge to this event. In modern automotive 4 stroke engines valve overlap occurs at all RPM, so for a short period of time the exhaust system is open to these low pressure influences which can suck things back towards the cylinder. if the exhaust gas velocity is low and pressure is high in the system, this will make everything turn around and go the opposite direction it's supposed to. If these gasses reach the cylinder they will dilute the incoming mixture with unburnable gasses and take up valuable space within the combustion chamber, thus lowering power output (and potentially pushing the intake charge temp beyond the fuel’s knock resistance). So having good velocity and therefore low pressure in the system is absolutely imperative to good power production at any RPM, you just have to remember that these concepts are also dependent on total flow volume. The overall volume of flow is important because it is entirely possible to have both high velocity and high pressure in the system, if there is simply not enough exhaust piping to handle the needed airflow."

in regards to that comment^, is it possible to re-gain exhaust velocity at low rpm's and idle by adding more fuel to the mixture ?? or does it not work like that ? or does this have to do with timing more than air/fuel ?

An SC will solve this for you You will have more positive pressure from the intake.

[akley88]

even with 2.5" exhaust and full bolt ons i dont go lower then 600 rpms at idle

[FeaRlezZ]

^ well it was just a thought but does anyone know how to raise idle with the FIC ??

[nokiauser]

Full bolt-on GS with 2.5" custom pipe and idle is still at 650.

[FeaRlezZ]

^ do either of u have the GT throttle body ??

[akley88]

Originally Posted by FeaRlezZ

^ do either of u have the GT throttle body ??

yeah

[Elemenohpee]

Originally Posted by FeaRlezZ

^ well it was just a thought but does anyone know how to raise idle with the FIC ??

Leave the car running and tweak the number the green block is on when its idleing, like ummmmm only by a few points. Worst thing that could happen is the car will shut off on you, but then all you have to do is change the numbers back. My idle is at like 1,200 on a cold start and 650 at a warmed up engine temp

[FeaRlezZ]

Originally Posted by Elemenohpee

Leave the car running and tweak the number the green block is on when its idleing, like ummmmm only by a few points. Worst thing that could happen is the car will shut off on you, but then all you have to do is change the numbers back. My idle is at like 1,200 on a cold start and 650 at a warmed up engine temp

so when the engine is warmed up and running right ? and wut map am i tweaking ??

[nokiauser]

Originally Posted by FeaRlezZ

^ do either of u have the GT throttle body ??

I think my signature speaks for itself. Though I do need a tune bad. Too much of the backfire.

[FeaRlezZ]

^ ya u get a fuk ton of valve overlap untuned

[akley88]

Originally Posted by nokiauser

I think my signature speaks for itself. Though I do need a tune bad. Too much of the backfire.

mine backfires constantly. afr's hit 10.0 all the time

[Elemenohpee]

Originally Posted by FeaRlezZ

so when the engine is warmed up and running right ? and wut map am i tweaking ??

Use the stock bypass map that was loaded by darkside, their was a thread BrianJ had on it which has been used by the GS people to calibrate the F/iC. That map shouldnt change anything really.

Wait your fuel trims are set to 0 or are you funning a Fuel map, I tuned mine once I already had a map installed so it was a bit easier to guess how much to move the numbers, if that makes sense

[tcsoccer09]

really think it depends wat temp it is...i feel like in the summer its closer to 700 and winter more toward 500...its almost like it doesnt wanna wake up when its that cold

[FeaRlezZ]

Originally Posted by Elemenohpee

Use the stock bypass map that was loaded by darkside, their was a thread BrianJ had on it which has been used by the GS people to calibrate the F/iC. That map shouldnt change anything really.

Wait your fuel trims are set to 0 or are you funning a Fuel map, I tuned mine once I already had a map installed so it was a bit easier to guess how much to move the numbers, if that makes sense

i am running a fuel map now

of course my computer is not letting me open the files for some reason but ya i think i got the idea down.