asking if my very weak cold idle is a result of a mechanical issue or can it be tuned out.

car runs well, idles well enough warm and hot, but wants to idle cold at about 250 rpm.
iow not. would like to see a more oe type warm up idle of 1500. takes about three blocks or so before it will maintain idle. or I guess till the coolant gets over 130

car has largish cams and is set to idle at 1050. have tried high timing and low timing As well as trying richer or leaner afr.

ecu tuned and running V7. 96530706

 

Have you messed with the ISCV stepper table at all?

 

This has been discussed.....

https://www.evolutionm.net/forums/ec...-searched.html

 

sorry Paul, nothing in that thread really addresses my issue, and Ive tried a lot of the suggestions with no helpful effects.

you are a busy fellow.


lan, did some ISCV but I didn't find much effect there either.

 

Did you try the settings on the first page???

 

except for lean spool which I have bit offed


at one time I read you raised your biss through the roof, but then it seemed you had a high idle(?) . but on that page you only mention getting your biss close to the wanted idle.--which is about where I am.

 

what have you tried so far?

 

adjusted the unknown warm idle ign map
quit the low coolant timing adjust,
reset desired idle,
idle stability raised,
set idle stepper table to match the 015 map, tried that map with higher numbers.

 

How many ISC steps at idle?

 

this morning, 50 degrees coolant, start was at 78 drifting down over time

now that meant I had to hold throttle to keep it running.

 

have you adjusted your biss?

 

Adjust the BISS and set it until you see about 20 + or - 5 ISC steps at idle. turn off the car, restart it and let it relearn ISC steps from start up to idle and then let it idle for about 5 minutes and readjust BISS to get 20 ISC steps if it is off. You may also need to pull fo the IAC and give it a cleaning also... Hope that helps.

One more thing to mention, make sure and check fuel trims afterwards sometimes adjusting the BISS will through off the fuel trims.

 

Is your LTFT low below +/- 5%

What MAF Hz are you idleing at ?

What is your timing looking like in 60 and below load and 1500 and below rpm?

 

hz 37

low and mid less than 5% at extremes, average near zero

timing has ranged from 17, currently around 10 ~12


freddy you talking warm idle, isc right?

 

Correct