my motor is confused

Post by **MikeDombeck** » Wed Sep 23, 2009 8:46 am

i dont know what to check here, but i had my car on the dyno today and it made 328whp on 15psi which is great, the problem is it runs like s*** between 4900 and 5100 rpm... if u look at the fuel map it seems my car doesnt know what rpm or throttle im at if im at 3000 and full throttle it bounces back and forth from 2000 and 7000... if im at 5000 it does the same thing... has anyone ever had this issue, and what could cause this?

Post by **the converted** » Wed Sep 23, 2009 10:11 am

Do you have your dyno sheet? Were they logging a/f when you were doing you runs? what engine management?

Post by **MikeDombeck** » Wed Sep 23, 2009 11:55 am

greddy emanage, i have the dyno sheet but i dont have a scanner. af never dropped below 11.5 or above 12.2 in boost... it runs fine out of boost or if im full throttle from a higher gear.. but when i try to do a pull it does that weird thing i mentioned...

Post by **the converted** » Wed Sep 23, 2009 11:58 am

Done a compression test on it recently? That is pretty rich.

Post by **MikeDombeck** » Wed Sep 23, 2009 4:13 pm

i dont think it has anything to do with fuel. when we were tuning we jumped all over the range for fuel from 14 all the way to 10... the part that shows u on the map where ur reading for rpm and throttle jumps all over then chart and is not supposed to, what would cause that.. a bad tps? maybe a bad ground? i dont know what it is.

Post by **the converted** » Wed Sep 23, 2009 4:16 pm

You wouldn't happen to have data logs would you? Honestly it could be a ton of things.

Post by **MikeDombeck** » Wed Sep 23, 2009 4:25 pm

my tuner has them... all i have is the dyno sheet... its not the maf, no leaks, and plugs are perfect... i just wish i could explain what it looked like on the computer screen, the car would rev normal, but the ecu is reading all over the chart like im going from 1k to 8k to 5k to 3k to 7k at all percentages of throttle while im climbing up my rpm's... so its throwing the fuel for what it is reading i believe and thats what i think is causing it.

Post by **shift_SRDETuser** » Wed Sep 23, 2009 4:51 pm

MikeDombeck wrote:my tuner has them... all i have is the dyno sheet... its not the maf, no leaks, and plugs are perfect... i just wish i could explain what it looked like on the computer screen, the car would rev normal, but the ecu is reading all over the chart like im going from 1k to 8k to 5k to 3k to 7k at all percentages of throttle while im climbing up my rpm's... so its throwing the fuel for what it is reading i believe and thats what i think is causing it.

I know nothing about greddy emanage but I do know apexi power fc --- there are different systems for different gen sr20s there are about 4 or 5 different ecus made for each series of sr20det. That is what comes to mind that it is either wiring into the ecu causing it get messed up readings or the ecu is jacked. Verify the series of sr20det you have and make sure it corresponds to the correct ecu you have.

Post by **MikeDombeck** » Wed Sep 23, 2009 5:02 pm

i have two s15 ecu's.. it does it on both. i thought that too.. it only did this after i got the new turbo, ever since i got it i havent been running right. im going to replace the tps when i can find one, im hoping thats it. maybe the stock ecu was running in limp mode and i never noticed it.

shift_SRDETuser wrote:
I know nothing about greddy emanage but I do know apexi power fc --- there are different systems for different gen sr20s there are about 4 or 5 different ecus made for each series of sr20det. That is what comes to mind that it is either wiring into the ecu causing it get messed up readings or the ecu is jacked. Verify the series of sr20det you have and make sure it corresponds to the correct ecu you have.

Post by **Seishuku** » Wed Sep 23, 2009 5:52 pm

Sounds like a bad ground, or damaged shielded wire (like on the CAS).

Post by **the converted** » Thu Sep 24, 2009 7:03 am

Doesn't sound like a TPS issue to me. What wire(s) did you tap the emanage into for tach signal? I think there might be some signal noise on that connection causing the issues.

Post by **MikeDombeck** » Thu Sep 24, 2009 8:21 am

i bought a plug and play harness, didnt tap into anything, i will make sure all connections are tight and secure, but it does it before the emanage. the rpm read crazy on the dyno screen also.

Post by **Seishuku** » Thu Sep 24, 2009 11:19 am

Check around the coil pack harness too, there might be a bad wire that might be causing noise somewhere.

Post by **MikeDombeck** » Thu Sep 24, 2009 11:36 am

Seishuku wrote:Check around the coil pack harness too, there might be a bad wire that might be causing noise somewhere.

i did reground the coil pack ground because it snapped off like 2 months ago.. i checked it thou and it is holding up fine, i groudned it to the intake manifold with another ground on there...

Post by **MikeDombeck** » Sat Sep 26, 2009 11:30 am

i got the fsm and all sensors are fine as i can tell... i learned today if i start from a high gear it will run thru with no problem, could it be because i am running with no air filter.. my tuner said it should be fine... its a z32 with the screen so i wasnt too worried about any debres

my motor is confused

my motor is confused

Re: my motor is confused (MikeDombeck)

Re: my motor is confused (the converted)

Re: my motor is confused (MikeDombeck)

Re: my motor is confused (the converted)

Re: my motor is confused (MikeDombeck)

Re: my motor is confused (the converted)

Re: my motor is confused (MikeDombeck)

Re: my motor is confused (shift_SRDETuser)

Re: my motor is confused (MikeDombeck)

Re: my motor is confused (MikeDombeck)

Re: my motor is confused (the converted)

Re: my motor is confused (MikeDombeck)

Re: my motor is confused (Seishuku)

Re: my motor is confused (MikeDombeck)

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