I'll try to make this as short as possible. I was reading in one of the tuner mags the other day that some turbo cars in this case it was a supra go into a safe mode(dropping boost or pulling time) when the engine detonates.
Question 1: Does the Evo have this feature?
Question 2: What would cause my car to detonate in this situation. Last week I'm getting on the highway in fifth gear doing about 50 or 55,it's about 65 degrees outside,I roll on the gas and the car starts to ping for the first time ever. I always run 93 octane gas (even buy it at the same station almost everytime). The only mods I have done are a K&N drop in filter a ground kit and tein high tech springs. None of which should have anything to do with detonating. My car has 9,000 miles on it still with the original spark plugs. Then I noticed last night when coming to a stoplight when i put it in neutral and started to brake the engine was stumbling a bit like it was forgetting how to idle. I'm going to call the dealer and have them check it out but, if you guys have any ideas I would greatly appreciate them.

 

26 veiws and no replies, thanks guys. Has any one elses Evo detonated for no apparent reason?

 

I've never heard any detonating on my car, but that doesn't really mean it hasn't happened. I do know now after installing a boost gauge that I have the biggest boost spikes if I go WOT in 5th at 3000rpm. I really never do that in my normal driving but I was testing the boost gauge and trying to find out what would cause the biggest boost spike and that is definately it. Sounds like the situation you had except you heard pinging and I never have.

The stock ecu will pull timing when detonation occurs that much I know. You may have gotten a bad tank of gas? Lower octane is what I would suspect if it's never occured before.

I've read many post about the Evo stumbling when coming to a stop. Most people said adding the grounding kit did help. Mine has done that on occasion but not recently. I also have 9000+ miles on my car with a flash, 3" turboback, grounding kit.

Maybe go get some more gas and see if it continues before going to the dealer. Really it sounds like you didn't acctually get 93 octane.

 

I was thinking it was bad gas too, the only thing that got me was it has only done it that one time.

 

question to # 1, yes Evo has this on it too.