New to evolutionm.net and I've got a problem :(
 

Hey whats up, I'm the proud new owner of an evo and I recently joined this site so that I could learn more about my evo. I have several friends who own DSM's and I also recently purchased a 1g for cheap to play around with so I'm not totally in the dark when it comes to these cars.

I've been doing a lot of reading lately and I'm glad I have because I am having some trouble with my car. I'll just describe the situation and what I plan to do about it... if anyone has any information to add that could be helpful then it would be much appreciated.

SO I bought this car about 3 months ago from a dealership. It is a 2003 evo and it currently has 41k on it, and the only mods are a 3 inch cat back exhaust and a boost gauge. Up until 2 days ago the car drove beautifully without a single problem but 2 days ago it started to have a rattling noise coming from underneath the car. Its really hard to pinpoint and I'm thinking its coming from the exhaust but I'm not sure. I dont have a garage and its been way to cold and wet outside to get underneath and check it out further. The real problem is that ever since the car started rattling it has had absolutely no power... it accelerates like crap. The boost builds very slow ely and tops out at about 13-14psi when before it would spike to 19 and taper back to 16, exactly as a stock evo should.

So I'm assuming that the rattling and the lack of power are related. I'm planning on making a boost leak tester and testing that out on my next day off. I'm also going to isolate that rattling and fix it if I can. Something that I have done already is reset the ECU. After reseting the ECU and letting the car idle for a few minutes I took it out for a drive and it seemed to have its full power for the first minute of driving. Then once the ECU adjusted it went back to being sluggish. Do you think it could be the car registering the rattling as knock and retard the timing? The rattling is quite loud so is that possible? Would that also account for the low peak boost?

The rattling wasnt horrible at first and as it got louder the car seemed to drive worse and worse. Now it seems to idle badly too. The idle will fluctuate a bit up and down every few seconds. Also when I'm driving if I take the car out of gear to coast the rpms will drop down to below 500 and then surge back to 1000, then settle at 750. Sometimes if I'm braking and still holding the clutch in when it drops to less than 500 rpms the car will actually stall. Do the evo's have an ISC motor like the dsm's that can go bad and cause idle surge? Should I go ahead and check this too?

I'm pretty knew to diagnosing this kinda stuff and I am desperate to get my car back to running normal again. I have no idea what may have caused this because I baby this car. It literally happened overnight. Friday night it was fine, Saturday it started rattling and drove like crap.

Anyways, I will appreciate any help that I can get. Thx in advance for any advice,

Matt

Likely the downpipe is touching/rattling against the cross bars on the underside of the car. Check for rubbing and if they are remove the bars for a test run and see if that clears out the problem.

If you do find out its the problem you can add washers as spacers until they clear.

I would start with the obvious, check your manifold bolts, O2 housing, exhaust and intercooler couplers and make sure everything is tight. It is possible it was returned to stock and traded in, also check your connections on the stock BCS and make sure they are good and do a boost leak test. I hope you find your problem without alot of headaches{thumbup}

That is a good point to check for loose bolts.

As I didn't answer the question about the ECU retarding timing then YES it will and has for me when my downpipe started to rub against the lower cross bars. My helix exhaust aparently stretched the stock hangers just enough to start after awhile and the car when it rubbed ran like crap just as the OP states.

In fact if the ECU see's too much knocking false or not it will go into a low octane map which means low boost and timing :)

Hope that helps.

Thanks guys. I'm going to be doing all this tomorrow on my day off so I'll let ya know what I find.

Matt

goodluck with it, i'll be coming back to see what you found out.

Its been a while but I've determined that the Cat was clogged up restricting airflow a lot. I've got an extended warrenty so I took it in to Mitsu and I'm getting the cat replaced tomorrow under warrenty.

It seems logical too me to assume that a clogged cat would prevent the turbo from spooling up because virtually no airflow was getting through and the turbo requires a signifigant amount of flow in order to spool up.

My question is.... Why would the cat be clogged at 40k miles? How could it have gone from perfectly fine one day, to clogged the next? I'm worried that this could happen again, and I want to make sure that the source of the problem is fixed. I'd like to be able to tell Mitsu to look for what caused it and I'm not sure what would cause something like this. I did nothing out of the ordianary with the car in the first 2 months I owned it, so could it have been something done by the previous owner?

Matt

Evos on the stock tune tend to run very rich so that might be a good explanation as to why your cat is already clogged at 40K. Even though it just suddenly went bad, it was probably gradually getting worse and then it finally plugged up completely. Seems everybodys first mod on an Evo is a retune so it leans the motor out a bit improves the power and improves the gas mileage as well. Wish it didn't void the warranty though, otherwise I would have tuned mine months ago.

Is it possible for a squirrel to have crawled into the exhaust, seriously? Whats up neighbor. Good to see another naper/aurora Evo owner.

What dealer did you buy it from? If it is who I think it is I am surprised they would honor your warranty if you have an exhaust.

BAM! thats what I was gonna say. The previous owner for me put a Megan Racing TBE and it rattles sometimes when backing up, and sometimes taking off.

I was self conscious about it when I first got the car, but it doesn't bother me now. I'm hoping after I get Cobb's TBE I won't have that problem.

HAHA, MAX MADSEN ftl

I'm from Naper also

dingdingdingding

Good to see some other evos in Naperthrill :). Its possible I've seen some of you guys driving around. I've seen some nice evos driving around since I got my car. Its funny how you will start noticing other evos when you own one. I was always an evo lover lol, but never imagined I'd be owning one.

So didnt buy my car through a traditional dealership. I got it from a place that sells higher end sports cars through ebay. They are actually located in the Chicago suburbs so when I saw the car online I drove over and test drove it. Naturally I was in love, and one week later I was driving it home. I got an extended warrently through a 3rd party, which is working out to my advantage. Normally I wouldnt buy a car through an ebay company, but it was a sick deal, and I did get to test drive it first. Plus, other than this cat issue which is now fixed, the car is in flawless condition.

You are right, no Mitsu dealership would honor a warranty on my car (cause of the exhaust) if the warranty was through mitsu. But since mine is a third party, mitsu could care less since they dont have to pay for it. So they would love to fix anything that is not working on my car under this extended warranty cause they can just bill all of their rediculous labor and parts charges to this other company lol.

They actually called me when it was in getting the cat replaced and asked if I wanted several other small things fixed under the warranty too. I said hell yeah since it doesnt cost me a penny. They called up my warranty company and it was approved :).

Matt

I got mine from the dealer(NJ) with mods on it such as meagan header.....when that cracked i had it replaced under warranty, they tried to say first its an aftermarket header, so i said, i dont know what you are talkin about, i got the car from you!!!....low and behold, it got replaced :-)

LOL nice.