Hi guys,

Sorry I haven't been active for some time. Hope things are going well with you all.

My EVO IX is slightly modified and got it re-mapped 5yrs ago with 231kw@aw. A few months ago I did a dyno evaluation at the same place and result was 211.1kw@aw. I had a chat with the tuner the he reckons it could be because of number of reasons, the tuner didn't see any detonation or misfire or sluggishness etc.... He reckon it needs a re-tune and that will fix the problem as it is very common because its been 5yrs and I have done over 100,000kms since the tune so mostly it because of wear and tear. I asked if its the fuel pump (Walbro 255) which is over 5yrs old and does makes loud whinny noise every now and then sometimes very loud on cold morning start. he also found one of the injectors got a broken seal "which is not a huge problem" tuner quoted.

Car drives fine but I'm noticing some kinda roughness every now and then which has certainly something to do with the outside temperature I suppose. and when I feel the difference I can't hear the air intake noise as loud as normal when accelerating. Any idea what could be the reason?

Does a re-tune will fix the problem (excuse me if its a dump question)? I was advised my car needs to be re-tuned and checked at least once in a year. Is it correct? Any tips will be much appreciated, unfortunately I don't have any reliable mechanics/tuners near my place.

Thanks heaps.

 

Evos need regular maintenance to make sure they are producing the same power level for which they were tuned on.

Start at a boost leak test and see how many leaks you have. Lots of leaks causes Evos to run rough.

 

Thanks guys for all your inputs...
It was the Walbro 255 playing up, so I got it replaced with a new pump. Its now very quiet and responsive! I will get car re-tuned down the track anyway. Peace

 

I would still do a boost leak test.

 

Preventative maintenance never hurts!