fan probs

[gary@apt]

firstly hi guys

this is my first time playing with tune on a v8,ive always been a turbo man with 2.0 engines till now

ive got a nissan 200sx we have just fitted a 2006 ls2 from a gto in but have a few issues with the fan control

im using 2 fans with 2 relays but i under stand on 1 wire from ecu will switch but i have smaller fan running as soon as engine is started even when its cold

only way i can stop that is remove the 100 numbers in the acp table to 0 then it turns off but i cant get it switch on at certian temp

ive searched on here but most ref to fan info has a much more different options to mine

[ssvolvo]

Double check your fan wiring. Are you using the GTO OS in your E40 or an OS from a truck that had an engine driven fan? The truck OS will only ground 1 fan relay.

If all is well with wiring then put all the fan settings to stock and start over. Slowly lower your tables using the same percentages but at a lower temp.

If you have A/C then the ECM WILL NOT turn the compressor on. You must turn the A/C on manually, unless you have the BCM from the GTO. BUT...if you use the high side GM A/C sensor then the ECM will see high pressure and turn the fan on anyway, even though the ECM hasn't turned on the A/C.

Good Luck! John

[gary@apt]

hi

im using the std gto file os 12604792

what do the % represent?? voltage level??

im not using the ac the wire for pressure is just left loose but fan runs all time,but if i flash another tune with all values in fan power acp to 0 then fan wont work at all

[ssvolvo]

No because the relay is on or off, no in between. I've never been able to make heads or tales with it but after considerable f'ing around with I got it close enough.

[doubledip]

you will probably find that the way your tune is set up is to run with the % numbers for PWM fans like in corvettes - the reason why there are other numbers in there other than 0 and 100...

e38's are a very different beast to the LS1 PCM's

[gary@apt]

theres 3 options of fans to run

i think they were discrete,or pwm or magnetic

[doubledip]

Thats right and you need to have it set up correctly so it operates like an On/Off setup (if thats what you want) and not a gradual spin up (like Corvettes have in the states)