I have a question I was hoping someone could help me answer. I have an 03 evo with 45k on the ODO. It still has the original plugs. I started noticing recently what I would descirb as maybe running a little rough at speeds of say 25-35 mph. What seems to induce it is when I am in traffic holding a steady speed and am just barely giving it any gas. If I get on it is fine or if I am tached up more it seems fine. It is just at low RPMS. So my question is could it be the plugs or is there something else I should look at? It is just more annoying then anything at this point. Also I am getting no CEL at all either.

 

Oh yeah one thing I will add is that I notice sometimes when I start the car up from a cold start that my high idle shows this miss also. I guess I am trying to describ it this is what it is like mmmmmrmmmmmmmmmmmrmmmmmmmmmmmmmmrmmmmrmm. With M's being smooth and R's when I hear the miss.

 

With plugs being as cheap as they are you should try that first.

After that I am at a lose.

 

Ok I tried the NGK BPR7ES plugs and I also had the battery cable off while changing them thus reseting the ECU. The plugs didn't help. In fact I think the car ran a little better with stock plugs so I put them back. They were not bad and still look good so I don't think it is a plug issue.

I am guessing maybe a fuel issue such as a dirty injector or something? It only does it when you are barely touching the gas or the at a cold engine high idle. What do you guys think? Do you think fule injector cleaner might help and what type would you suggest? I am going to run a search and see what I come up with but if anyone has any ideas please let me know.

 

I think I am going to try some Lucas fuel system treatment and see if that helps. Let me know if anyone has any ideas.

If any mod reads could you move it to the correct forum for me please. I just noticed I posted it the wrong one. Thanks.

 

keep us updated...
i think i am having the same problem

 

Do you have a check engine light?

 

Nope no check engine light at all.

 

Stock clutch? I know what your thinking it can't be a clutch problem. But hold on one second, I had a similiar problem. At low RPMs the car just felt strange, when I got on it it would hesitate a little, especially if I got on it at lower RPMs, but ran just fine at high RPMs. I posted my problem on evom.net and nobody thought it was my clutch, because a badly slipping clutch problem is very noticeable. So I did the sparks plugs and was even planning on getting tuned again, when I talked to my brother in law and he was like, dude it's your clutch. He said I was at the beginning stages of a clutch on its way out and the problem would get worst everyday. He was right, it was my clutch and it got very noticeable. You see a lot of people know the signs for a badly slipping clutch, but when a clutch is just starting to slip they think something else is wrong, and what a lot of people don't realize is that when the clutch starts to slip it starts to go fast, everyday I drove the car it got worst. I'm not a 100% sure it is your clutch, could be a lot of things, but it wouldn't shock me one bit if it was your clutch. I mean this was my first clutch problem for any car that I've owned and honestly I never realized just how important the clutch is to a car. I got a new clutch and man it feels like I got a brand new EVO.

Last thing if your not on your stock clutch or you just recently installed a new clutch, the disregard my post

 

^^ I hope it is not the clutch that would suck. Yes, I am still on the stock clutch. I have had many other manual cars that clutch has went bad on. In fact my wifes Prizm's clutch has been slipping for about a year. She just babies it and we get by.


You might be on to something though I am noticing that when I start off or shift it is a little more touchy/jerky compared to how it used to be. I guess time will tell if it is clutch at least at this point it is not slipping at high rpms as I have done a few good hard pulls trying to see if it was going to cut out at all.

 

Stock cluth Sorry I know what your going through, I thought the same thing, can't be the clutch. I heard all the horrible stories of clutch problems and my problem just didn't seem similiar and when I posted my problem on here people didn't think it was my clutch either. Like I said many people know the signs of a very badly slipping clutch, I mean it is very noticeable, but not many people know when their clutch is just starting to take a turn for the worst. Just like you I thought I may be even misfiring or something and that is why I wanted to get tuned again and bought new plugs. But it turned out to be the clutch and boy when it gets bad, it gets bad. But I was able to baby it for a couple months, but I hated knowing that one of these days it was going to go and knowing my luck, it would probably happend at a horrible time. Seriously though I am pretty positive it is your clutch, but like you said only time will tell. The good thing is that from when I first noticed the problem tell when it got really bad was like two or three months and then I babied it for another two months, so I was able to hold off buying a new clutch for four to five months. But when I got the new clutch (and flywheel) I couldn't be any happier, car feels brand new. I got my clutch/flywheel and install all done for about $900.00. Good luck and hopefully it is a quick and inexpensive fix, but if it is clutch, it may be expensive, but it is worth it.

 

Also for other people who may read, my stock clutch lasted over 60 to 70 hard drag strip launches and I make over 300whp. I wish my clutch would have lasted longer, but honestly I was pleasently surprised it even lasted this long with all the abuse I put it through.

 

hey...i know u said you were gonna try Lucas

...if you haven't yet give SEAFOAM a shot...itll clean up all the carbon and residue in your engine and fuel system

 

^^ I tried the Lucas already today. I am going to run it some more and see if it changes at all. Sea foam was my second choice I might try that as well if the Lucas does no good.

 

I think I might have got it figured out. After the Lucus and plugs didn't get rid of it I started thinking about a dirty MAF sensor. So I went out and picked up some CRC MAF cleaner. I took my HKS RS filter off and then the MAF and all I had to say was damn it was dirty. The honey comb was black and the MAF Sensor was oily. FYI my air tube going to the turbo has a lot of oil in too. So I cleaned the MAF up and I was suprised at how much dirt was coming out. I cleaned it four times just to get everything out.

When I was done I reset the ECU and it took it for a drive. The throttle response is much better and NO studder or miss.

So I think it might be fixed time will tell for sure. I just wanted to post this for anyone that might be having the same issue.