Is this normal? Turbo boosting at light throttl

[tunethis]

I blew off my upper intercooler pipe coupling the other day and now I'm boosting differently. I tightened the coupling very good and now get boost at very light throttle. Especially in the gears past 1st. My idle is at -17 or -18 as usual but I don't understand why, all of a sudden, the turbo is boosting at such light throttle. If I lightly touch the pedal (I'm guessing around 10-20%), the turbo begins to boost. I don't know if this is normal because I'm thinking the coupling was probably loose and leaking since I bought the car. Does anyone have an idea why this is happening? I'll be able to do a boost leak test on Thursday or Friday.

Also, I just checked the turbo. I have quite a bit "side to side" and a slight bit of "in and out" shaft play. The wheel doesn't look like it scrapes the inlet and it spins freely. My car doesn't smoke at all but I have an even louder "spool" sound now after the coupler blew off.

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[silver bullit]

You had a boost leak and fixed it, full boost with the 14b/16g should be around 2500-3500

 

[tunethis]

You had a boost leak and fixed it, full boost with the 14b/16g should be around 2500-3500

Okay. I'll check to see exactly where I make full boost when I leave again.

 

[dalatinromeo]

I thought this was a joke when I read it but you were serious. I was thinking of the beer commericial with Bill Parcells and he goes, "But it's a good thing not a bad thing"

But yeah it sounds like you had a boost leak that was causing you not to spool properly you finally made enough boost and you caused your coupler to blow off. You fixed the leak, and now your car is running stronger.

Now for the shaft play, I won't worry if you car is driving normal. But be prepare for the turbo to go on you. But use it as an excuse to upgrade

 

[silver bullit]

May be getting time for a rebuild on the turbo, or upgrade.

 

[dsm-onster]

Is that a 47 I see on the compressor cover. Do you have an evo3 16g? You can upgrade to a td06 18g. That's about it for true bolt on upgrades. A turbine wheel clip is an upgrade. But neither for now. . . I didn't see injectors in your profile, but a 2g maf. So I'm assuming you have 550s. Nor do I see a fuel pump upgrade or intercooler upgrade. You have PLENTY of room to grow with this turbo. Even if you're running a small 16g, which can flow enough for 380 crank hp!!!

 

[tunethis]

I thought this was a joke when I read it but you were serious. I was thinking of the beer commericial with Bill Parcells and he goes, "But it's a good thing not a bad thing"

But yeah it sounds like you had a boost leak that was causing you not to spool properly you finally made enough boost and you caused your coupler to blow off. You fixed the leak, and now your car is running stronger.

Now for the shaft play, I won't worry if you car is driving normal. But be prepare for the turbo to go on you. But use it as an excuse to upgrade

I was use to seeing boost come on a certain way. Then, all of a sudden, I'm building boost easier after I blew off a coupler and fixed it. I just wanted to make sure everything was good with the turbo.

Is that a 47 I see on the compressor cover. Do you have an evo3 16g? You can upgrade to a td06 18g. That's about it for true bolt on upgrades. A turbine wheel clip is an upgrade. But neither for now. . . I didn't see injectors in your profile, but a 2g maf. So I'm assuming you have 550s. Nor do I see a fuel pump upgrade or intercooler upgrade. You have PLENTY of room to grow with this turbo. Even if you're running a small 16g, which can flow enough for 380 crank hp!!!

It looks like a 47 to me. I have no idea which 16g I have. I bought the car with that turbo. I don't do too much to the Eclipse since my 300M is not running right now. I don't have a back up if something went wrong. I've done the basic engine maintenance and once I get a new timing belt installed, I'll get the proper mods then get it tuned. The previous owner didn't say anything about upgraded fuel injectors. They look like stock "Blue Tops" to me. He said it has a Walbro 255 fuel pump though. With the 2g maf, it idles and runs good despite the lack of fuel management. I know it could be so much better. Eventually, I'll get a fuel pressure regulator, bigger injectors, and dsmlink. Also, I'm going to get a pocket logger very soon.

 

[dsm-onster]

It likely idles and drive in closed loop fine because the walbro 255 is overruning your fuel pressure regulator enough to cause the 450s to flow like 550s. It's entirely possible you're knocking in open loop once the fuel pressure regulator catches up to the walbro's fuel flow.

 

[tunethis]

It likely idles and drive in closed loop fine because the walbro 255 is overruning your fuel pressure regulator enough to cause the 450s to flow like 550s. It's entirely possible you're knocking in open loop once the fuel pressure regulator catches up to the walbro's fuel flow.

I see. I need to get the fuel pressure under control because the car does have some issues above 5000 rpms.

 

[dsm-onster]

If you get the fuel pressure under control, then you won't be able to idle properly. The walbro pump is overruning the fuel pressure regulator and forcing the fuel pressure to be high enough for the 450s to idle normally with the 2g maf. The 2g maf reads about 20% lower airflow than what the 1g ecu is expecting. Thus, the ecu is dialing back the injector pulsewidth greatly. . .And likely enough to compensate for the superhigh fuel pressure your walbro is outputting.

Run an adjustable fuel pressure regulator to bring your fuel pressure down. And put on a 1g maf. Adding the 2g maf is a mod that needs a logger on which to check so that you don't blow a head gasket.

Before you mod anything, of course get logging equipment. You have an evo3 16g. Definately worthy of larger injectors and fuel control. If you want to get more out of this turbo, get:

1. an adjustable fuel pressure regulator.
2. I'd pick up an SAFC and 650cc injectors since you already have a 2g maf. Start out with a 550cc injector tune and go from there with your logger. A 1g maf won't cut it. It won't read high enough volume flow for an evo3 16g. Which is maf overrun and an engine killer!
3. An ebay fmic and piping.
4. 1 stage colder plugs, if you're running the stock replacement plugs.

With the cost of a logger, $800-1000 . But, you'll be good for 400hp or so.

You already have a better fuel pump, better maf and intake piping for it, evo3 16g, better 1g bypass valve (do the dodge garage mod to it).

 

[tunethis]

If you get the fuel pressure under control, then you won't be able to idle properly. The walbro pump is overruning the fuel pressure regulator and forcing the fuel pressure to be high enough for the 450s to idle normally with the 2g maf. The 2g maf reads about 20% lower airflow than what the 1g ecu is expecting. Thus, the ecu is dialing back the injector pulsewidth greatly. . .And likely enough to compensate for the superhigh fuel pressure your walbro is outputting.

Run an adjustable fuel pressure regulator to bring your fuel pressure down. And put on a 1g maf. Adding the 2g maf is a mod that needs a logger on which to check so that you don't blow a head gasket.

Before you mod anything, of course get logging equipment. You have an evo3 16g. Definately worthy of larger injectors and fuel control. If you want to get more out of this turbo, get:

1. an adjustable fuel pressure regulator.
2. I'd pick up an SAFC and 650cc injectors since you already have a 2g maf. Start out with a 550cc injector tune and go from there with your logger. A 1g maf won't cut it. It won't read high enough volume flow for an evo3 16g. Which is maf overrun and an engine killer!
3. An ebay fmic and piping.
4. 1 stage colder plugs, if you're running the stock replacement plugs.

With the cost of a logger, $800-1000 . But, you'll be good for 400hp or so.

You already have a better fuel pump, better maf and intake piping for it, evo3 16g, better 1g bypass valve (do the dodge garage mod to it).

Thanks for the help. That clears up a lot. I'm saving the list above to make sure I get the correct supporting mods. I had no idea I was running the evo3 16g.

 

[chavez408]

Your the man matt!
By the way, clean VC what kind of paint is that?

 

[dsm-onster]

Glossy 500 degree engine paint. The more I paint black, the less oil leaks you see.