Piston numbe 4 gave out on my 03 evo. Now I have to hone out the cylinder walls and buy a new piston. The only thing that is done to my car is full exhaust, intake and Autronic Stand Alone. I don't think it was the Autronic b/c we have two other evo that were part of are shop, and about 5 other ones with the map.

Just wanted to know if you guys and gals heard this happening?

 

What grade of fuel do you use?

 

This is the first I have heard of. How much Boost did it see before that problem?
Don't you have to get a whole new set of pistons too otherwise it won't be balanced, no?
Chalk on up for Autronic.
Subscribed.

 

What happened to the piston? Ran too lean most likely.

 

It seems like #4 is the first to go. #4 was the first to go on the DSMs and it seems the evos are the same way. I melted a few #4s on my GSX...all were tuning related
What where your A/F ratios?

 

my friend cracked a piston in his Evo. He had Cams, TBE, Cone Filter, Fuel Pump, Headstuds and Reflash. His piston broke in nearly half. He was only pushing about 335 whp at ~22 psi on 93 Octane. The guess is that it was a casting defect from the factory. Luckily the cylinder wall was not damaged, just a very very light scuff.

 

funny this comes up...I just walked in from the repair shop up the street from my house...My Evo broke down last week and I finally towed it in...Diagnosed as piston #4 burned up...no compression...****...dealership doesnt know yet..they WILL be fixing this or taking the car back, only has 24k miles and is the cleanest and best kept Evo that I know of...I have been running stock boost on 95 octane as you can get that at the pump here...OH might as well mention my car was broken into while at the shop, everything taken out and my whole trunk and wing is fizzucked bc the stupid bastards tried to pry it off..

 

thanks for the fast reply.
I was running rich I'm for sure, you could smell it, Always put 93 in a couple of times I put 92 in but mostly 93!

 

hum...had a guy down here have a piston go bad on him toowith less than 12k miles... maybe this is serious????

 

I have a print out of my a/f it is WAY SAFe...what is your dealer saying???

 

well guys I may need all the help I can get, but Mitsu is gonna have to pay for this one...hell they already cost me a 1000 for a clutch at 20k miles..car is a daily driver and pampered..

 

My autronic is keeping my boost at a 19psi all the way to 7k I lower my redline to 7200k just to keep it safe! I would like to get a set of forge piston but then I have to take it to the maching shop and I'm a little short on cash, I just about have eough to get it fix with just replacing the one piston!

But I still love the evo!

 

I love the car, but this is not my fault, why do you feel you should pay? car has warranty right?

 

There have been a few piston failures in the Dallas are, I do not know who, but the machine shop I go to has done 3-4 engines so far from pistons going south. I do not know what the cause was for those engines though.

 

joey would you happen to know who paid for the repairs??