Ok so i recently posted question about a problem with starting my car when warm. I want to note that this problem has become much worse with my injen hard pipe intake. When running just an open turbo and no intake or filter it doesnt happen as much. I am running an 2003 Evo ecu with Tephra mod V7 9563.

With that said. Untill today I wasnt able to datalog during start this problem. But today I did. What I see in my logs is really off the wall. After digging more into the 9563 rom I think this might be related to an issue with the rom itself. Being that I am using it on a 92 DSM which it wasnt intended for I might be creating the perfect storm for this to happen.

Here is my experience, With the coolant temp warmed up (160+) I try to start the car and it will stumble very hard, backfire via the intake and exhaust, When blurping the throttle it doesnt really help clear it out, it kind of just enhances the problem and stalls. Today I had to wait 20 mins to start the car.. Looking at the logs, I see with an RPM of 90 during cranking the timing begins to drop from 5 to -20 and the STFT will "BOUNCE" from -23 to positive 24%. I havent see this ever before. Now when the car is cool and lets say the first start of the day. It will fire right up with no issues. Idle very smooth, with an AFR of 14.7 "hunting" from 14.6 to 14.9. When I experience this problem my AFR is off the guage. "---" ALSO if that isnt enough, I also logged an RPM of 6250 @14% Throttle position, and -23% STFT with a load of near 300. This is very odd. Has anyone else seen something out of tephra rom 9563?? I have been working on the coolant and startup tables thinking that I have values that are very EVO specific and my sensors are tossing values to the ECU that are causing this. But then again I have been searching and seeing on some other less traveled forums that simular issues with STFT have been experienced with this rom. Now this was in 2009, so I need to check the revision of my rom to see if this has been revised since then. Some have experienced problems with the intake on and sure enough I started testing and with the intake off and just turbo, (I have a translator no MAF, running a GM 3" MAS) it doesnt happen as bad. but it does still happen. I need some help here.

I am experienced with engineering and code so for the other tech guys I will understand you. I am still a bit green to the structor of the ECU and how the code calls memory registers, But I do understand memory management and the stack. I am attaching a quick screenies from EVOscan.

 

I had a similar problem and log like this turns out to be bad battery and cable . Log and watch battery voltage during cranking and when things go crazy in the log voltage will drop . this mite be your problem ? I love seeing 270 load and 34652 mph in the drive way with .4volt on throttle

 

If you log while cranking the car, the data can get out of sync and everything you grab will be false data.

I have heard there is some special request you use for logging during start up.