A few weeks ago I was at Buttonwillow for a track event and during the last session, my motor started to run a little awkward. The motor started sputtering and misfiring when I was in WOT and the powerband felt weak from 5000rpm and up. Also, my water temp gauge rose above the normal temp line just a bit. I pulled the car back to the pit and noticed the coolant overflow tank was nearly full. I couldn't diagnose the issue at that time and the car drove fine when it was not in WOT so I called it a day and drove it back home.

Next week I pulled the spark plugs out and the plugs in cylinder 3 and 4 had broken electrode tips. It wasn't the whole electrode but just the tips. Cylinder 1 and 2 were normal. The plugs in 3 and 4 seemed like they were still sparking but just at a huge gap. I replaced all four spark plugs hoping that would fix my problem. It kinda fixed it but the motor still does not feel right.

I did a couple WOT runs in 2nd and 3rd gear and the powerband feels OK but it seems to take a little bit longer than normal to pick up power when boost hits. It kinda feels like turbo lag but I'm still running the stock Evo 8 10.5 turbo. I also noticed the motor was ticking louder than normal at idle. I used to have a faint ticking noise under idle but now its even more noticeable than before.

Today I take the car to my friends shop to do a compression test and borescope check. Looking at the borescope did not find anything unusual on the pistons and walls. My friend checked on the ticking noise by tapping on the throttle and you can hear a loud tick every time we tapped on the throttle. He told me the noise sounds like its coming from the bottom end so we put the car on the lift and confirmed the noise is indeed coming from the bottom end. I have no idea what is causing the ticking noise.

Compression test results:
Cyl 1 - 130
Cyl 2 - 130
Cyl 3 - 125
Cyl 4 - 120

Basically the motor does not feel 100% power wise. Any idea what is wrong with the motor or what could have caused this? Are there any other type of tests I should perform next? The car is mainly used for track days now but I don't want to keep running it and waiting for a failure to happen when I'm on the track.

Power mods on the car
2005 Evo 8 tuned at 25psi tapering to 22-21psi on 91 octane. 3-port boost controller. HKS 264/272 cams. Perrin intake and intercooler. Aftermarket UICP and LICP. 2.75" Downpipe, 100 cell cat, 80mm catback.

 

I hope I am wrong on all counts but (deep breath) here goes....

Detonation
Head lifted
Rod bearing

 

I'm thinking it's the rob bearing as well.

Maybe its time for a built shortblock.

 

take the oil filter off and cut it apart, inspect for metal!

 

I'll do that this weekend.

 

Just service my car few days ago and noticed there are quite a lot of micro metal particles sticking onto my magnetic oil sump nut.

When rub on it the particles is as fine as powder...

Is it a sign of rod bearing failing?

 

You sound like you might have what happened to me. My engine started to eat plugs and couldn't figure out why. Even went so far as to pull off a piece sitting on the top of the piston one day when car fell flat on its face... detonation is your issue and if your not careful its going to do this:

 

yes

 

DAM!!! I just rebuilt my car almost 1 year ago...

 

what state are you located and what type of oil are you running?

 

Im on the other end of the globe and im using Motul 6100 - 15-50 and hope its a genuine oil we get in Malaysia...

 

You know you should be running 300V James!

 

Mike my Guru...Is it really a sign of failure when there is present of micro metal particles on the magnetic oil sump nut?

 

chu got it rt mang.

 

Sorry for my closed minded thinking.. forget sometimes this is an international board

15-50 huh?

I know FL and Malaysia are 2 diff places but we do tend to share the blazing heat temps.. I'm running 20-50.. I'm wondering if the diff is what is causing the bearings to crap out on you