I have been fighting with a friends 03 EVO 8 for the last week, we put in a set of PTE 1000cc injectors and upgraded to the Tephra V7 rom at the same time. I put in the recommended scaling and latency for the injectors and ended up tweaking the latency a bit and now the fuel trims are great. The car runs and drives well when hot but requires you to put your foot on the gas pedal to start it. After some more tweaking it now starts hot without touching the pedal but idles low and rough for 30 seconds and then it jumps up to the normal 1000 rpm idle.

When cold the car starts right up with just a little pressure from your foot on the throttle but when you let your foot off the car tries to idle at ~500rpm and dies. When the car is hot it idles at the 1000rpm the ECU is set for and I adjusted the BISS using Evoscan. I took about 40% out of the injector cranking enrichment IPW adder main table and it seemed to start quicker. At one point it seemed like it was just way rich after starting so I zeroed out both post primer enrich tables and saw no change. AFRs tend to hunt around when trying to idle cold, I am not sure what I am missing and have searched a ton of threads. Any advise would be appreciated.

The car also has Kelford 272 cams, Buschur ported intake and TB, exhaust, and we use crap 91 octane out here.

 

Did you mess with the stepper tables at all?

 

At one point I had turned up the desired ISCV to see if that would help and I don't think it did, right now the neutral desired ISCV initial step position is at:

145
145
145
131
122
113
95
68

I know the bottom couple should be a lot lower in a stock file.

 

If you still need to press the throttle to start it, then its still getting too much fuel at start up..

What do you have the idle rpm set at?

 

Target idle is 1000 rpm warm 14-1500 cold. I have seen the car raise the idle to 1200 when it is hot and intake temps go up so I know it can do it itself but when the car is cold it acts like the ISCV does nothing.

 

I ended up replacing the ISCV with a new one and now the car starts fine hot and cold but I now have the high idle problem

When I hot start the car it idles at 900 rpm which is where the idle is set via the BISS and using evoscan to kill the ISCV. As soon as I touch the gas pedal and let it fall back to idle the car slowly raises it's rev to 1500-1600. The whole time EVOscan is showing ISCV steps at 60. EVOscan shows the desired idle of 1000 rpm but the car acts like it doesn't care.

So in summary the car fires much easier with the new ISCV, I returned the desired step position tables to stock and even lowered some of the values but I still get an uncontrollable idle. I am going blind looking through different threads, can anyone tell me why I have a step reading of 60 when it is mapped for 7 based on temperature? I see about 77 steps KOEO and then it hangs out at 58-60 and makes the car idle high.

 

did you reset the biss again?

 

Yes, right now in SAS mode it runs at 900 rpm. I took the car for a drive and it wanted to idle at about 1800 while moving. When I came back I let the car run for about 15 minutes parked at idle and the revs slowly dropped to about 1000 where it should be and the ISCV steps were around 30. I then rev'd the car up and the idle hung out around 1200 or so. It seems to be adapting but still floating around. What tables is the car pulling from to make it act all crazy? I can only imagine what it will do when it cools down and I try to cold start it again.