I have a 2003 Evo 8 with the following perfomance related mods:
AMS Intercooler
Injen Intake #IS1898P with upper intercooler pipe
Greddy Catch Can
Random Technology HighFlow Cat
HKS HiPower Exhaust
The turbo and downpipe are standard.

My Service Engince light is coming on and has thrown a number of codes for:
Mass Air Flow Sensor check
Wastegate Solenoid check
Wastegate System fault

The dealer (as well as a local perfomance shop) has checked the MAFS and the Solenoid and both are OK. The dealer reset the codes and it drove fine for about 120 miles (day and a half) and then the light came back on when accelerating onto a freeway. The engine appeared to slightly "misfire" in 2nd at about 4Krpm. It agains appears to be perfoming OK. Am taking it back to the dealer to get the code rechecked and further diagnostics. Two days ago they said it appeared to be running very nicely after the codes had been reset and the learning history removed.

I know the turbo fins are worn at the corners but other than that, I am not sure what else might be wrong.

Any ideas what to check or what the issue might be?

Thanks,

 

One thing I would like to know how you know your turbine blades are worn? That must mean you took the stock turbo off and if you did, its possible a vacume hose or the wastegate itself was not put back on properly and is venting wrong. Idea number 2, have you recently cleaned your filter? Sometimes people that use K&N's clean the filter and put WAY too much oil on them. This fouls up the MAF and causes issues. Be fortunate that the dealer is willing to reset the codes for you. If they checked the BOV, wastage and MAF and say all is ok, then they will most likely say its one of your mods. Its just one of those crazy things. Maybe email Vishnu or RoadRace and ask around. Good Luck with it.

 

The performance shop indicated that the fins were worn but did not remove the turbo (apparently about a 5 hour r/i effort).

 

are you tuned yet?

 

Random Technology HighFlow Cat


$100 says that's what's causing your code.

 

Go and find out what the code is how hard is it. Go to autozone they do it for free.

 

The engine has not been tuned after the mods.

I will check on the codes again ... the Service Engine Soon light went off on its own for a few hours but came back on today.

 

"100 says that's what's causing your code."

if it was the cat, he would be throwing a code for a faulty o2 sensor, not maf or wastegate codes.
i would tend to think its your intake, how long after you installed it did the light come on? i also agree with checking the filter, check you lines, and waste gate, or get that thing tuned and see what happens.

 

The light came on shortly afer the AMS Intercooler and Injen Intake were added. These were done just a week or so apart from one another. The new filter probably thru oil on the MAF but has the MAF has since been cleaned, checked and rechecked. The filter has not been cleaned or reoiled. The vacuum lines have been checked and the wastegate holds pressure (tested at about 16lbs). After the MAF was cleaned, checked, etc, the Catch Can was added and the spark plugs changed. The codes were there before and continue to reappear. The cat was changed at the same time as the orig failed.

What would be the normal changes when it is retuned.

 

Why would you put a larger intercooler on with your mods and or the Injen Intake? Those are mods to be done after some more basic ones like MBC, new downpipe, test pipe, flash and or tune, cams, etc. I have heard/read that without a tune aftermarket intakes will cause your car to run worse than without it. I would bet your car would be faster if you put the stock intake and intercooler back on.

 

really? so if i got a aftermarket intercooler and lower intercooler piping (AMS intercooler) and all my mods are a jdm mr bov, a hallman boost controller on 20psi, that id lose power?