I need some help trying to diagnose my random cel and loss of power,

I own a 2001 v7 bugeye, ej207, vf30, 1 high flow cat, GFB MBC, Apexi hiFlow power intake, Walbro 500, Dual core radiator, 4eat tranny.. running only on 98 Octane, (comparable to us 93? i think)

All been tuned for the mods.. I had some clown drive into the front of me about 4 months ago and it hasn't been running the same since. (iv'e had the car repaired since then) *cosmetically anyway...

Loss of power, my butt dyno tells me it's just not pulling as hard (compared to when I was off the dyno) anymore,

If I start pulling say from, 1st-2nd I will get a random cel flash around 5000rpm, it will flash on for 1 second, then it's gone,

If i'm doing a long pull from 2nd-3rd I will also get a flash around 5000-7000rpm *

I took it to the local workshop and they couldn't fine a single code! nothing was stored!

So far I have swapped the plugs with the new Irridium NGK+7 range as per the JDM manual, but they were fine, the engine has only 40,000km on it,... Could it be possible the impact has knocked the cambelt timimg/tooth or somthing? i'm not sure..

(btw I can't use a accessport as it's not avaiable for the JDM)..I so wish tho..

Any help boys & girls?