I have a 2003 Evo 8 with 37,000 miles on it. For the last few months I have noticed a decrease in performance. Acceleration is not as dramatic as it once was and I blow brownish smoke out the back when I stamp the throttle.

Another symptom I have noticed is that it sometimes "misses" when starting. Not sure if that is the correct term but what it feels like is that the engine kicks back against the starter motor. At first I thought the starter was just going bad, so I replaced it but over the last couple months the same symptom is creeping back in again.

Can anyone advise me on what I should look for in terms of getting her back to peak performance?

I'm going to change plugs and wires immediately, but what about timing belt? Could it be that I need a new belt after only 37K?

Just need some advice on where to start.

p.s. Mods include: DC Sports 3" downpipe and cat-less exhaust and Vishnu Racing computer (using Stage 0, 93 Octane map).

 

I wouldn't do the wires, you could change the plugs if it would make you feel better. I would suggest maybe doing a compression test, and getting rid of that computer and going with a custom tune from a reputable tuner in the area on teh stock ecu.

As far as the starting issue, I have no idea.

Your t-belt should be fine with only 37k on the clock.

 

Sounds like your basic tune up stuff. Change the plugs and wires. Make sure your plugs are gapped correctly. You shouldn't need a timing belt yet.

 

Boost leak test

 

+1^

 

Brownish smoke on WOT is completely normal...

As for the "lost performance", you might just be getting used to it. I'm at almost 400whp and it doesn't feel very fast anymore

 

new plugs and some good gas should do the trick. who did the tune in the car?

 

you've probably gotten used to the car's usual power. time for more power! lol

 

all kidding aside, this is probably true. go ahead and change your plugs and do a boost leak test...pay close attention to your throttle body since it is VERY common for shaft seals to leak around your mileage. so check that out, pick up some cams or something else and take a ride over to TTP in Orlando...if ur in tampa it shoulndt be more than a couple hr drive...they'll straighten you out

 

Its about 75-90min to us here in Orlando, we have all of the proper tools to test and diagnose the car from compression and leakdown tests to Snap-On in cylinder cameras, boost leak testers, plugs, parts, and the know how to comb through the engine to look for the usual suspects such as loose vacuum lines, PCV and EGR problems.

Give us a call at 407- 475-0010 and we'll take care of you.

 

^^^^ damn y'all dont play around... hahaha but to the op.. these guys can tune u up real nice