No Boost?!?!?!

[mattxhand]

Ran the MSP on the dyno today. 74 horsepower (argh)

The guy only ran it up to 3500RPM because it was running so lean. He also said I was pushing 0 boost whatsoever.

This is a completely new problem. I've noticed that for the past day it's been holding back until 5000RPM and once it hits it, it will literally throw me back in the seat and take off. The turbo is spooling, it's turkeying, the wastegate is working, my BPV is fine, and all the connections are good.

A couple members of the forum suggested that I get a boost gauge so I picked one up and ran it to the cabin. The vacuum is at 22 and the boost is picking up slowly but surely to 6psi.


Any ideas?

 

[destineal]

Don't you need to go past 3500 for boost? If they dyno man didn't push it past 3500 because its running so lean, why would you? you need a A/F ratio guage I guess. I'll be back in a sec

 

[mattxhand]

But that's the thing, it runs fine any other day.

 

[destineal]

Ok I did 60 in 3rd gear at 4500RPM with no boost so it is possible to run 0 boost i guess. Not WOT of course. Did you pay for the dyno runs? I wouldn't pay if it was only being pushed to 3500rpms and running lean. Can you post video of your boost gauge response?
FYI i'm no expert and I'm mostly rambling, but I'm the best you got until the gurus arrive(wiggle)

 

[Ricktalife]

You can hit boost well before 3500 with our small turbo. I would definitely get an Air Fuel gauge as it is a necessity on a turbocharged car.

 

[bast525]

I saw that run dude... you were running SUPER lean on the first run. Then they ran the car a few more times (you got like 6 runs yeah?), and you were still getting this lean spike like 16:1 at lower RPM I'd say around 3000-3500, then it would richen up nicely and you made really good power after that.

You need some way of richening it up when the turbo first starts to spool. Do you have any method of tuning fuel at all?

 

[destineal]

when should it be hit in 1st gear?

 

[bast525]

when should it be hit in 1st gear?

?

When should what be hit? sorry if that wasn't directed at me...

 

[StealthWyvern]

?

When should what be hit? sorry if that wasn't directed at me...

I think he is asking about when should he hit full boost in 1st gear.

 

[bast525]

I think he is asking about when should he hit full boost in 1st gear.

Um... I dunno? stock turbo? I would think 2500 rpm? maybe 3000? on the MS3 it's about 3000 in all gears.

 

[destineal]

even when granny driving?

 

[haze20]

It was me that ran six times at the end. I made 201whp and 245wtq. They only did one half pull on his car and he was at almost 15:1 a/f at 3500rpm WOT. They took the car right off the dyno after that.

 

[destineal]

oh ok yea thats pretty lean

 

[bast525]

no man, full boost at 2500 rpm at full throttle. just regular driving around you shouldn't boosting at all or maybe a couple psi.

haze 20 - did you have some sort of tuning method for fuel? It looked like your first pull was very lean, then a long time passed to the next pull... it started out too lean again but then richened up to nice levels. but you can see where that lean spot when boost is first building is causing a major power dip.

 

[haze20]

At what RPM are you hitting 6psi?

Nope no ECU. The car is almost completely stock. I have front and rear motor mounts, Vibrant s-pipe back exhaust, MBC and a K&N filter. The MBC was causing a spike at the first hit of boost and went real lean. The first pull was at 10psi and then settled to around 8psi. I was playing with the boost controller between runs. On the last run it spiked to almost 15psi but settled to 11psi.

 

[destineal]

 

[mattxhand]

I'm hitting it at about 4k

 

[bast525]

Haze be careful man... I don't know if it's your injectors or if it's the ECU not being able to figure out what's going on or what, but yeah every time your boost spikes it was going way lean... I'd either turn boost down or look up some of the tricks you can do with an MBC to limit spiking..... or just get a better boost controller.

16:1 air/fuel is dangerous man...

 

[haze20]

The MBC was only on for the dyno day. The car only runs 10psi with a spike to maybe 11psi daily. The car doesn't see boost most of the time anyway.

 

[J_Naoto]

Ran the MSP on the dyno today. 74 horsepower (argh)

The guy only ran it up to 3500RPM because it was running so lean. He also said I was pushing 0 boost whatsoever.

This is a completely new problem. I've noticed that for the past day it's been holding back until 5000RPM and once it hits it, it will literally throw me back in the seat and take off. The turbo is spooling, it's turkeying, the wastegate is working, my BPV is fine, and all the connections are good.

A couple members of the forum suggested that I get a boost gauge so I picked one up and ran it to the cabin. The vacuum is at 22 and the boost is picking up slowly but surely to 6psi.


Any ideas?

hope you figure it out soon. since the vacuum is normal, maybe try getting the wastegate changed