Since Im an Evo noob, I really need some help with this. Just last week I brought my Evo in for the tranny,tcase and diff fluid change( $150) + 27 point inspection. After the fluid change and inspection was finished, the mech wrote me a report. This is what it said:

1. Rough idling maybe cause of the spark plugs.

2. Large chunk of metal came out from the diff.

Later the service manager came and told me I still had the 60k warranty on my car. So I asked him if I could replace the diff and his response was " Well, you know what, after you bring your car back in for the 60k maintenance( replacing all the belts) I could call Mitsubishi and tell them your taking good care of your car and hopefully them will replace it for you.

So my first question is, the rough idling part. Since I bought my car used, it already came with an aftermarket exhaust, evo 9 bov and downpiping. Everytime I start my car, the sound from the exhaust sounds like its from a subby. So could it be that I have cams on it or not( How can I tell if I have cams)? When I bought my car, the salesmen already told me they did an oil change, replaced sparks and topped off all fuild.

Honestly, the car runs really good and I cant seem to find a problem with it.

 

Check for boost leaks first, that could give you a bit of a rough idle. TB seals might need to be replaced since it is an VIII and a few years old.
As far as the Diff is concerned I would want to know what the "Large chunk of metal" was, have the shop inspect it, worse case it costs you a few Hrs. worth of labor since your car has a warranty.

 

Just wondering tho, do cams give off rough idling?

 

mitsubishi sucks for warranty. I was told that my o2 sensor was not under warranty,"because we suspect you modified the car." What the ****! do a little searching here and you will find all the answers you need.

 

not a rough persay. you tube it.

 

Well honestly I dont see any leaks and the mitsubishi mech told me to just change my spark plugs to fix the rough idling. But the thing is that they were replaced a few hundred miles ago. Also, I cant seem to find any leaks as most of the tubes are all brand new but after I get off work, I'll try to look harder.

 

Is it an inconsistent idle or an offbeat idle? If it is just idling all over the place it could be a result of poor tuning, MAF issues, or something more serious that I wouldnt even know where to start... If it is consistent but offbeat, you may have some big cams. The only way to tell is to have a local that knows Evos check it out and tell you from the sound and condition of the car. Otherwise you will have to pull the valve cover and try to find some stamped inscriptions on the actual cam. Good luck!

 

Consistent wise, I think it is consistent. Being offbeat, I really dont know cuz I dont know whats the normal idle for an Evo. When I first start my car in the morning, it idles at 1.3-1.4k and when its warmed up, it idles at about 7-800. So is that normal? The only thing that I thought was wrong was the agressive rumbling noise it makes( sounds good tho). Other than that, I really dont know why the mech said I had rough idling.

 

could it be misfore?

 

Dont think so, cuz if it was, wouldnt the engine light pop up?

 

By consistent, I mean is it a constantly repeating sound or is it all over the place? That warm up and idling RPM is normal. Maybe you just have some big cams in there?

 

i thought idle should be around 950 rpms. mine idles around there constantly when it drops lower you can hear it in the car for sure. maybe im wrong but i thought normal evo idle was 950. I think you need to get your car retuned

 

The sound or rumbling is really consistent. Anyways, let's just say the car has cams in them, would the cams shorten the life of the motor? Yes I know I'm really a noob >.<

 

lol no they will not just give you more power but again just build the head and no worries upgrade spring retainers and your set. you really dont even have to do that but still. I plan on getting a ported/polished 1mm valve dual spring retainer with either kelfords or bf cams but do whatever you want its yoru evo

 

thanks a lot for the info bro=] I got worried for a little bit.