has power til 5500

[awdtsi90built]

its kinda weird just got car cant figure out problem wont idle since it over loads and dies running 7.6 at idle 10.3 when on pedal it hits 5500 falls on its face but it will go to like 6 if u throttle it like a quarter of the way would my profec mess wit this

 

[2GFWDbeast]

Sounds like you have a bad boost leak. You know what spark plugs are in it?

 

[awdtsi90built]

ngk wit ngk wires this car has over 10gs worth of work and it is useless til i figure this out

 

[2GFWDbeast]

You bought a car with 10grand into it? I bought a car that had 15g and it turned out to be a pain in the ass!!!!! had to stick 5 grand into it. Start with a boost leak test see if there are any leaks.

 

[awdtsi90built]

i dont think boost leak would cause it to run that rich and have power from ground to 5500 when it cuts out got good vacuum and boost has one of those supposed to recirc hks bov think it might be able to handle the boost

 

[dexterholland04]

You need to tell us a little more about the car if we are to help you better. What is done to it? Did you do a boost leak test? Are your plugs and wires new/plugs gapped correctly?

 

[2GFWDbeast]

a boost leak would definitely cause it to run rich. If your only getting power to 5500 what happens after that? Is it a sudden stop or sputter or what?

 

[awdtsi90built]

the only thing stock in the motor is cams crank 8.5.1 pistons .20 over stainless valves manly rods valve spring kit head deck block decked cleen less than 2g on motor

 

[2GFWDbeast]

You didnt answer my question what does it do? Sudden stop or start to sputter or what.

 

[awdtsi90built]

it it feels like fuel cut out but how if running rich kinda jerky wants to pull thru it but slows in rpm gain and tries to pick up while it is still falling on its face

sudden stop more so

 

[my dreamt dsm]

What??? What does honda has to do with this ... and yes I would drive a honda... it is a wiser choice over a turbo dsm if you ask me... especially liability wise.

 

[awdtsi90built]

car runs and pulls like a champ til then

 

[2GFWDbeast]

The boost leak would cause it to run rich. Fuel cut could be a number of things. Fouled out plugs, maf, really bad boost leak, the tune what do you have for tuning on the car? You sure the car has a 190 or 255 pump. I would double check to see if it has one.

 

[Jafro]

It's a boost leak. My bet is your turbo peaks at 5500 generating enough force to make the leak bad enough to gag your engine with too much fuel. If you're leaking air after it passes through the MAF sensor, you're leaking metered air and that will undoubtedly make your car run rich.

YouTube - Boost Leak Testing 201: Using the tool.

A stock regulator with a Walbro 255 will also do what you're describing as the regulator fails. Which that combination inevitably causes...

You'd know it if it was fuel cut.

Bad spark plug wires fail the worst at high RPMs. But I don't even know if you're running coil-on-plug or the factory coil to offer better advice.

Bypass the profec and see if it still does it?

 

[awdtsi90built]

fuel system stock turbo stock only pushin 12lbs at the moment stock tune all stock electronics should be fine i would think not much was changed just up graded and lil different compression

 

[2GFWDbeast]

plugs or boost leak or a combo of both

 

[awdtsi90built]

you think i would pull a 21 vacuum at idle wit a boost leak and running a 7.6 air fuel its got brand new denso oem fpr

coil pack and wires are brandnew

 

[WeaselHack]

Engrish Anyone?

You are hitting fuel cut. Do the ### boost leak test!!!!

7.6:1 A/F??? What gauge are you using to determine that?

 

[awdtsi90built]

inovate wide band used for gauge only

### would be a good boost limit for 851 wit stock fuel and turbo components

 

[rlacasse1]

Dude, what the hell are you saying? I haven't been able to understand a single post.

 

[awdtsi90built]

wont idle running rich at idle 7.6 should be around 15 and when throttle is pushed comes down to 10.3 wont rev past 5500 rpm

 

[WeaselHack]

Im not sure what a good boost level would be for 851...

If you mean 8.5:1 then I wouldn't go beyond 16lbs assuming you don't run lean and have some other way of monitoring the engine - knock, timing, etc.


How did that boost leak test go?

 

[awdtsi90built]

its 2 in the morning thats tomorrow job if its not boost leak then ### else would make it run so rich i mean its not good what should my full throttle number be

 

[Jafro]

Vacuum and boost are very different. It's air pressure that opens up leaks, not the other way around. Anything that leaks under vacuum pressure isn't going seal up when you boost it, but you can have a sealed intake under vacuum that opens up and leaks under boost. You're also not pulling an atmosphere of vacuum. But the most critical point you're trying to make is negated by the fact that your vacuum pressure is metered from BEHIND the throttle plate, and your boost leak is occurring in front of it.

If a boost leak test isn't the first thing you do when you have a fuel issue, you haven't owned a turbo car long enough. No other tests are relevant if you don't verify it's holding all the air in. What your boost gauge is telling you is irrelevant because there's a throttle plate involved, blocking off 95% of your intake from what it's metering.

 

[WeaselHack]

wont idle running rich at idle 7.6 should be around 15 and when throttle is pushed comes down to 10.3 wont rev past 5500 rpm

I think you are putting too much trust in your instruments. You are making a huge assumption and its distracting you from properly troubleshooting your issue.

Use the tried and true process of elimination. Do yourself and everyone trying to help you resolve this and perform the following:

1a: Learn to use a shift key.
1b: Boot leak test.
2: Verify you are running 450 injectors.
3: Verify you are running a stock fuel pump - just to be safe, invest in a AFPR.
4: Verify your base timing.
5: Purchase a data logger to monitor other sensors.

Report back once you've done at least step 1, 2 and 4.