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Running Lean, and high boost.

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littlereddsm

Probationary Member
9
0
Dec 19, 2006
Oceanside, California
Hello. I'm new to this forum, so of course I shall post in the newbie section. I have a problem with my 2G Eclispe. Right now it is running super lean and then if you try accel hard it hesitates bad at 4-5,000 rpm and not going higher. My guess for that is because it doesn't have enough fuel. the thing is my car keeps getting a check engine little saying it is taking to long to get into open loop. Here is the story with the car though because it has be sitting for a while. The car blow its engine 2 1/2 years ago and i finally had the money to put in a new engine. I bought one from those used Japanese engine places and put it in. I hooked up everything back to the way it was, and it started right up. I just got done hooking up my air/fuel gauage and it doesn't even register half the time as anything, but when I downshift then it finally goes into the lean section. Also it runs really high boost on my boost gauge. It says it is bossting at 25 psi. I know that can't be right, especially since it is a stock turbo. Other then the lean problem, and boost the car runs good. It drives 65 when I first took it out without the air/fuel gauge hooked up. I didn't know it was running that lean until then. I have a 24R front mount intercooler, and a Greddy Type RS blow-off vavle, and a cold air intake. Other then that the car is stock engine nothing done to it. I was just wondering why my car is doing this. Almost forgot to mention that once the car warms up it idles at 1,500-2,000 rpm. I would trouble shoot more of the electroics, but the Chilton manual sucks at that stuff. I did check the IAT already and that works fine. Please help. Thank you all in advance.
 
when the car first is turned on the ecu makes it idle higher and later it should drop. If you're running 25 psi, that could be your problem without any kind of fuel. Why don't you run stock boost and see how it feels. Also the a/f gauges aren't real accurate unless you have a wideband. Though they do make a nice light show. I would turn the boost down and see how it acts or get a datalogger and see if you're getting knock.
 
That's the thing. I don't know how to change the boost on a stock turbo. I'm not sure why it is bossting so high.
 
I guess you don't have a boost controller. Check the wastegate actuator on the turbo make sure its on there correctly the pin came out of mine and it about came disconnected. Someone else will have to tell you more about the actuator, because i don't know alot about it. I don't know what else would make you run that much boost..
 
I have a boost controller, but it's not hooked up right now. I suppose I could hook it up and see what happens. I'll have to take a look at the turbo tonight for that pin and see what is up with it. It is kinda wierd too, cause when it is idling it is running lean too. I'm kinda leanig towards a fuel pump for the lean problem, but i don't know.
 
I would check the vacuum line going to the wastegate to make sure it is properly installed. If the boost gauge says 25 your boosting 25 and thats not good for your new motor without some other mods.

Also with you A/F gauge...The only time that they read accurate is at WOT. They will just bounce around and so fourth any other time. To me it seems like you have a bad o2 sensor though.
 
While you are at it change the fuel filter. It gets over looked and causes a lot of fuel delivery problems
If you are just starting, a boost gauge and a logger are a great way to keep your car running longer.
Its nice to see what going on under the hood while you thrash around town.
 
I'll check the lines tonight, and change out the O2 sensor. I already changed the fuel filter and that really didn't help. Could it maybe be the fuel that is 2 1/2 years old? I put in octane booster and some fuel cleaner along with 5 gallons of new fuel, but I wonder if it is still from that old fuel. Thanks for the suggestions so far.
 
Are you sure that it is a stock turbo? 2g eclipses come with a T-25 which can almost never hit 25psi. You might want to check to make sure your Mass air sensor is hooked up because I couldnt even hit that high or boost if I tried without hitting fuel cut.
Also are you sure that you have the A/F gauge hooked up correctly?
 
If you've got a JDM motor, you've probably got a 14b or 16g variant on there. Hook the line from the wastegate up to the j-pipe or compressor housing which should give you even lower than stock boost (8-9 psi) and see how the car feels. The gas is probably not doing much for you car either. It sounds like your o2 sensor is dying/dead, but I would check it with a logger to see if it cycles at idle. If not, replace it. Usually when the sensor dies your car would run super rich though.
 
Tired switching the O2 sensor but it snapped off of course. Tomarrow I'm going to take the whole turbo off and put the one on that came with the car stock and see what happens. I'll have to see if I can get some numbers off of it to see what it is. Also I'm pretty sure that my air/fuel gauge is hooked up right. I found a diagram on the internet I think from this forum that showed where to hook it up to on the ecu. Tomarrow night though I shall see if the other turbo makes a difference. Thanks for all the help and suggestions so far.
 
heres a link on how to install A/F. just in case.http://roadraceengineering.com/instructions/afmeterinstallinstructions.htm

I wouldnt go through the trouble (if I were you) taking off the turbo when you should be able to tell what type of turbo is on there right now by simply looking at it. Besides that, any turbo besides the stock t-25 is most likly an upgrade that you will want to keep on the car

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thats a 16g it looks the same as a 14b just different when you look at the fins on the inside
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14b
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and good for nothing T-25
 

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I'd leave the turbo on and trying working around the problem like that ### your going to want to keep the upgraded turbo on anyway. maybe put the boost controller on and crank it all the way down or do what was suggested by hooking the line from the wastegate up to the jpipe. Can you talk to the guy you bought it from and ask him if there is something he did or a problem he knew about ?
 
The j-pipe is the pipe connecting to the cold side of the turbo, which connects the turbo to your intercooler piping. As stated, it should have a little nipple fitting on it where you should connect a vacuum line to your wastegate. This will make the wastegate open as soon as possible, so you'll run as low boost as you can before the exhaust gasses blow the wastegate flapper door open.
 
Well I figured it out. My turbo on the car had a bad wastegate. It was stuck shut so all the pressure was going into the engine hence my 25 psi boost. I switched turbo's and now it runs a lot better. It still idles at 1,500 or so though and don't know why. It only does it once the car warms up. Any suggestions. Thank you.
 
I tryed. There was no way that wastegate was moving, and I had the exact same turbo as I took off laying around so I put that on. I was beating on the wategate vavle and everything and it wouldn't move.
 
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