Hey guys, I am having a little trouble with my evo 8.

When I give about 30% or more throttle my car does this weird noise like it is bogging down and I feel a loss of power.

If I keep under that 30% throttle I can run through the gears just fine at any rpm, but as soon as I give it too much throttle the problem occurs.

I have tested spark, and boost and everything looks fine. While car was in the air and could not duplicate the problem.

I am thinking it has something to do with fuel line, but that is just a guess. Are fuel filters replaceable on the evo 8?

Any info would be awesome. Thanks in advance for your time!

 

Hey guys, just bumping this back up as I am still having the issue... As I was replacing my radiator I had to release the waste gate actuator and when I was attaching it back on I noticed that it was extremely stiff or tight, almost stuck at first? Is this normal to be this tight? Do you think it might be related to my problem? let me know, thanks guys

 

Yah thats normal. You have any CEL? You said you checked spark, does that mean you replaced your spark plugs? Have you done a boost leak test?

 

Have you datalogged at all, are you throwing a check engine light? Stupid one to ask but are your battery terminals clean and on tightly? I would check for a leak as biggie suggested and go from there but verify your not throwing a code it sounds like car is going into limp mode .

 

How many miles on the vehicle? Check spark plug gap and spark plug condition. Boost leak test the vehicle.

 

Sounds to me like your tune is way off. What mods do you have and has it been tuned. If it does not do it on the lift that means the car has to have a load on it for the problem to occur. With a load on the car the timing and fuel blocks you will hit are completly different. Could be a MAF problem too.

 

A friends had similar problems yesterday during autox. Have you checked intercooler pipes thoroughly First J-pipe to intercooler then other side of intercooler to upper intercooler. Check for rips or tears. Common problem is usually from the J-pipe to intercooler it will slide out under heavy load. Physically get under there and check with your hand t-bolts/clamps are holding piping in place.

 

Thanks guys.. I will look over what you guys have said.. I did throw a check engine light this morning, so I will be checking what that is all about..

Thursday night I replaced my radiator from stock to a aluminum mishimoto..
After I did so my idling has been funny, dropping down to about 400-500 rpms, then steady at the normal 850, then bumping up to a 1000 rpms.. seems very sporadic..

Also is it normal for the temperature to never get up to where is used to be with the stock radiator? With the stock radiator once the car was heated up the temp would sit right below the half way mark.. With the new radiator the temp gets to a little more than a 1/3 once heated, and will drop down, occasionally. Not sure what that is all about?

Thanks everyone!

 

115000 miles, had her since she was 6

 

I would double check all connection points. Forgot to clamp down a hose connecting the IX DV and OEM snorkel on a test drive. Got into boost and heard a loud pop followed by fluctuating RPMS at idle. CEL code? Get your Evo fixed? Thermostat maybe stuck open, have a data logger to check water coolant temps?