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2G Just bought my first 99 GS-T, emission control unit problem?

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rambow70

10+ Year Contributor
96
0
Feb 26, 2012
Fishers, Indiana
Just bought my first dsm! A 1999 eclipse gst automatic. It was owned by a girl and is 100% stock, even the air box and mufflers are the same. So basically, its just a stock car. It has 131k on the car and everything electronic in the interior like the power windows ect work perfect. Windows don't wobble, doors lock, and it even came with stock chrome wheels!

There is an issue with the car however. She told me that I need a new emission control unit which cost around $90 dollars. I am not sure what that is. But here is what the car does. I apply the accelerator and the car sputters and it loses boost/power. If I push it slowly at 5% ish throttle it builds to the third factory boost gauge bar and holds until I press the gas further and then it stutters and loses all power pretty much. So it doesn't seem like a boost leak if it holds until more throttle is applied? What do you guys think? No oil or coolant leaks, I think it burns a little oil due to a bad valve cover gasket. The check engine light is on. I might go autozone it but I do not have it insured. It was going to be a long going project that I was going to start later and I was going to tow it to bloomington, can't risk getting pulled over in it. So that is why I haven't hooked it up to a reader yet. But do you guys have any idea?
 
It could still be a boost leak. It may not have enough pressure at low boost to leak.

Do boost leaks trigger the check engine light upon start up? Could it be an egr problem? Or a bad o2 sensor? I own a 3000gt so I am not foreign to these cars completely but I have never heard of a emissions control unit? Unless that's a bad o2 or egr? I will search the forums on how to do a boost leak test, this is my first turbo car.

Also how can I make the stock bov whistle? My girlfriend owned a gst for a few months and it had the stock blow off valve, metal pre turbo pipe, and a fmic. If I get a metal pre turbo pipe, the one that leads from the maf to the compressor would it make a more distinguished noise? Or do you need the entire inter cooler piping to be aluminum? I want to keep the car stock for now.
 
Do boost leaks trigger the check engine light upon start up? Could it be an egr problem? Or a bad o2 sensor? I own a 3000gt so I am not foreign to these cars completely but I have never heard of a emissions control unit? Unless that's a bad o2 or egr? I will search the forums on how to do a boost leak test, this is my first turbo car.

Also how can I make the stock bov whistle? My girlfriend owned a gst for a few months and it had the stock blow off valve, metal pre turbo pipe, and a fmic. If I get a metal pre turbo pipe, the one that leads from the maf to the compressor would it make a more distinguished noise? Or do you need the entire inter cooler piping to be aluminum? I want to keep the car stock for now.

I haven't heard of an emissions control unit either. And I don't think a boost leak would throw a CEL. I would get a code reader on it, and we can go from there.

And on the BOV, I'm not sure. I run a HKS bov with aluminum piping and I like it.
 
I haven't heard of an emissions control unit either. And I don't think a boost leak would throw a CEL. I would get a code reader on it, and we can go from there.

And on the BOV, I'm not sure. I run a HKS bov with aluminum piping and I like it.
My girl friends was the stock one and it sounded like a ninja drawing his blade from his hostler, it was the best noise ever! It wasn't too loud like an aftermarket one but its sound was incredible, and like I said it was a stock bov. I might buy one of those aluminum pre turbo pipes to try it out. Maybe ill take my licenses plate off my 3000 and take it to auto zone haha

anyone know if advanced auto parts does free readings?
 
It could be many things. You will need to have the codes read & fix any & all issues. I would also get new spark plugs while messing with the other stuff. Make sure you only use NGK brand & stock is BPR6ES or BPR6EKN. These are the OEM plugs & the BPR6ES are cheaper but, for me; the BPR6EKN's have worked just as good.
 
It could be many things. You will need to have the codes read & fix any & all issues. I would also get new spark plugs while messing with the other stuff. Make sure you only use NGK brand & stock is BPR6ES or BPR6EKN. These are the OEM plugs & the BPR6ES are cheaper but, for me; the BPR6EKN's have worked just as good.
Oh for sure I will. I am going to be doing a lot of maintenance on it. New plugs, wires, air filter, valve cover gasket, fix my check engine, leak down comp test, and see if it needs aligned. Also I have a small bit of rust on my strut tower. I am probably going to sand it back as much as I can and spray paint it to protect it.

My main thing was just seeing what an emissions control unit was. Yea I'm just going to take her in, thanks guys, happy to finally own one of these! It was a Christmas gift to myself haha
 
Im pretty sure advanced auto does free readings, but don't quote me. Do you have any relatives or anybody nearby that has a code reader?

Update: I did take it to advance auto where the guy hooked up the obdII and then started revving my car up. I have never had anyone do this for a code check ever. After 10min of him playing around with my throttle and me asking him several times what codes it was throwing he just told me to buy some spark plugs.

I guess it could be a misfire, under load it does sputter so I will change the plugs and probably the coil packs. I picked up a spray bottle and I am going to hunt down a boost leak if there is one. When I trailer it to Bloomington this week I will stop by another shop and see if they will actually tell me the codes. But who knows, maybe I am lucky and it is just the plugs or coils!
 
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Update: I did take it to advance auto where the guy hooked up the obdII and then started revving my car up. I have never had anyone do this for a code check ever. After 10min of him playing around with my throttle and me asking him several times what codes it was throwing he just told me to buy some spark plugs.

I guess it could be a misfire, under load it does sputter so I will change the plugs and probably the coil packs. I picked up a spray bottle and I am going to hunt down a boost leak if there is one. When I trailer it to Bloomington this week I will stop by another shop and see if they will actually tell me the codes. But who knows, maybe I am lucky and it is just the plugs or coils!

Well that didn't really help at all then. I wonder why he wouldn't tell you the codes. Maybe he thinks because he has a code reader he's a mechanic.
 
Go to a different autozone and ask them to read the codes. Don't forget to change that fuel filter. It's time to change that for sure.
That's a good idea to add to the tune up list, how difficult is it space wise? I know for the 3000gt's they are almost impossible to get off, you have to wedge your wrench on the body of the car to break it loose.
 
From experience...and here's my guess and .02

The "emission control unit" that they told you was wrong, is really the ECU "engine computer unit" ...my guess it because they probably took it to a mechanic and they said "ECU " and they pretty made up the abbreviation "emission control unit".

My guess is that the autozone"retard" employee, hooked up the scanner and tried to read the scanner ...and it didn't throw any codes...and this is usually a sign of bad ECU.
A bad ECU would let you read any codes. It'll just show you a Check engine light. I'm just sharing my experience ..because I once had an auto Gst with the same symptoms it was a bad ecu..

Change the spark plugs ..just to make sure , do the tune up you usually do on a newly bought car...

The symptoms still exist...try testing pulling the ECU and check for fried caps.
 
That's a good idea to add to the tune up list, how difficult is it space wise? I know for the 3000gt's they are almost impossible to get off, you have to wedge your wrench on the body of the car to break it loose.
After you remove the battery tray and support bracket for battery tray there is ample room. I did mine in about 20 minutes. 2 19mm wrenches and a socket should git r done.
 
From experience...and here's my guess and .02

The "emission control unit" that they told you was wrong, is really the ECU "engine computer unit" ...my guess it because they probably took it to a mechanic and they said "ECU " and they pretty made up the abbreviation "emission control unit".

My guess is that the autozone"retard" employee, hooked up the scanner and tried to read the scanner ...and it didn't throw any codes...and this is usually a sign of bad ECU.
A bad ECU would let you read any codes. It'll just show you a Check engine light. I'm just sharing my experience ..because I once had an auto Gst with the same symptoms it was a bad ecu..

Change the spark plugs ..just to make sure , do the tune up you usually do on a newly bought car...

The symptoms still exist...try testing pulling the ECU and check for fried caps.

I am good with computers so I will check it for bad caps or anything. Might even rebuild it myself if it is toast. But when he hooked up the reader and he watched the fuel and air and he said it was fine. Could a broken ecu still give the obd2 readings from its sensors?

Also side question, I am thinking about gutting my precat but leaving my second cat. Is there a way to deactivate the down stream o2 sensor? 3sx has them for the 3000's, are there any for dsm's? Would the one in the link below work? http://www.3sx.com/store/comersus_viewItemBundle.asp?idProduct=769

I am thinking about doing this with the maintenance to free up some power but still have a stock car. Plus hoping to do some bay cleaning as well. My factory muffler is also a little rusty and sags so i might chop it, weld a magnaflow cylinder style muffler to it in the car and weld a 2.5inch outlet pipe out the back. Trying to stay away from fart cannon stereotypes. I am thinking about welding a flange like Tom did (tom's turbo garage) on his lexus type F so I can swap the factory one back in at any time. So I'm excited on that too :)

Thanks for all the help guys! It is too cold to start these maintenance things right away, my pockets are hurting after that purchase, but when tax return time rolls around hopefully I can put some work on it!
 
I changed the sparkplugs on my gst. Once and since they were not the traditional gappers.. they were like a four prong that didn't need gapped and were specific to my car. Well it sputtered under boost.
Did what u are describing.

I bought the ngks. And gapped. 28 and drove perfect[DOUBLEPOST=1417365246][/DOUBLEPOST]Impropper gap will caust sputter under boost
 
I changed the sparkplugs on my gst. Once and since they were not the traditional gappers.. they were like a four prong that didn't need gapped and were specific to my car. Well it sputtered under boost.
Did what u are describing.

I bought the ngks. And gapped. 28 and drove perfect[DOUBLEPOST=1417365246][/DOUBLEPOST]Impropper gap will caust sputter under boost
Just bought a set of gappers, the feeler gauge type, I have heard mixed reviews on those and the disk wire ones. The set I picked up has .28 so when I buy my plugs they will be gaped properly.
 
This looka like someone tried to do a tuneup and put the wrong spark plugs.

Because the way u describe the symptoms my car did the exact same when I put those platinum iridiums

the sputter didn't start til boost built pressure
 
This looka like someone tried to do a tuneup and put the wrong spark plugs.

Because the way u describe the symptoms my car did the exact same when I put those platinum iridiums

the sputter didn't start til boost built pressure
Well it is stock so hopefully I can avoid most dsm problems for now haha! I have heard to go with factory replacement copper ngk's, that is what I am going to do. Did yours throw an engine code?
 
No code for that it just ran like crap

tried to accelerate and it was sputtering under boost loosing power.. i pulled over and ripped them out put my old plugs in and was fine.

another thing is they may not be torqued down properly so put oem or ngk and torque then down.
i rink it was 22 lbs or so but look it up because i can't remember but improper torque will cause misfire also[DOUBLEPOST=1417368502][/DOUBLEPOST]And I recommend u don't go to autozone. They hire people that don't have parts or car repair experience.


I like oreilys in my opinion or advance..

u ever notice autozone has younger employees
 
No code for that it just ran like crap

tried to accelerate and it was sputtering under boost loosing power.. i pulled over and ripped them out put my old plugs in and was fine.

another thing is they may not be torqued down properly so put oem or ngk and torque then down.
i rink it was 22 lbs or so but look it up because i can't remember but improper torque will cause misfire also[DOUBLEPOST=1417368502][/DOUBLEPOST]And I recommend u don't go to autozone. They hire people that don't have parts or car repair experience.


I like oreilys in my opinion or advance..

u ever notice autozone has younger employees
I went to advance not autozone. Well I still need to track down that check engine light so I will take it to autozone because they ALWAYS give me codes, that was the first time going to advance and I was not impressed.
 
+100 on the plugs. when I got mine, it would sputter and chug like hell only when I started hitting positive pressure about 1/3-1/2 of factory gauge. But I found non turbo plugs in their, got new ones and all was good. Hope it's that easy for you also.

I wouldn't be too worried about modding/upping the cars power just yet. It's up to you but get it running properly first.

But good luck bro and enjoy modding :dsm::laser: Motors
 
When I bought my 98 tsi someone had Bosch platinum plus four plugs in it . Caused the exact same issue. These plugs run like garbage in our cars. Replace the plugs and if still have issue check ecu. I have not ran into a u pull auto parts that wouldn't let you swap in a used ecu to check it before buying it so it's an easy cheap way to check....
 
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