jimbos_viii

Evening Gents

Having an issue with cold starts on my Evo 8. Ill attached the tune. So pretty much It will crank on first turn, but the car will not idle up to warm up. It sits @ 1000 RPM and starts to stumble/miss and cut itself off unless i apply throttle and force it to run around 1700 rpm for 30 or so seconds in which the stumbling goes away and the car is able to eventually even itself out. If it sits a few hours but isnt completely cold it will also buck on the next startup and i will have to apply throttle to get it to start. Ive had a tuner adjust the coolant temperature idle table to try and idle it up while cold but it didn't change anything. Anyone mind taking a look and making a few changes to help me out?

Thanks!

k4nnon

Hey iv had this happen to me with cold starts before. It could be a few different issues in the tune that could make this condition better or worse but taking a look at some fuel trims could determine if there is an adjustment needed that could help solve your issue. Could also be stepper motor related or even a boost leak somewhere. It could be one of many things lol, just takes some looking into to figure out. Other than that maybe try this,, next time you try to cold start your car, turn the key on but dont start the engine, let the o2 sensor warm up for about 30 seconds before firing the engine. Sometimes if the o2 sensor doesnt heat up enough it can make cold starts weird. When it gets less than 20*F or so i find that my car will start better if i let the o2 sensor warm up before i start the car. If you get anything figured out be sure to post up the info, best of luck.