Boost cutting out at 10lbs. What can it be?

[mexburito]

The GN was running great then started doing the weirdest thing where it cuts out at 10lbs and seems like somebody is turning my power off but the car doesn't die. The car drives and idles great when not in boost. I changed ignition coil, module, 85mm maf, maf translator and even a computer. I checked all the grounds also. I ran out of ideas. I have checked the scanmaster readings and all the reading are appropriate. Fuel pressure seems to be good also. I do have a new chip on order but I don't know. Like I said I am running out of ideas. I just don't know where to go from here. Any advice is greatly appreciated .

 

[dank GN]

Look for leaks in hoses and your exsaust . What boost controller u Runin

 

[Mr.Spool]

85mm maf, maf translator

measure the voltage on the wirepin adapter.

 

[mexburito]

I actually took all the hoses off and checked them. I also checked the exhaust and no leaks. I have a turbonetics manual boost controller.

 

[mexburito]

Measuring the voltage on the wirepin adapter will be next then . Thanks guys.

 

[Reggie West]

Check the wastegate. You are duming boost because the gate opens at 10 psi on the stock spring inside it.

You need to check your hoses going to and from the gate and the controllerto make sure they are installed correctly.

You said it yourself, all the readings are good on the computer then it has to be mechanical.

 

[mexburito]

I am going to take off the wastegate and reinstall it. ASAP Makes sense. Thanks

 

[josh young]

Is it heat soak related, or does it do it cold? I had a similar issue, but it started at about 15 #'s. It turned out to be the cam sensor cap. You might try unplugging it with the motor running and see how it does.

 

[mexburito]

It does it cold or warm. I did disconnect it already after another forum member suggested it. Thanks.

 

[GNRick]

Sounds like my car when the fuel pump was failing.

 

[mexburito]

I have a fuel pressure gauge inside the car.

 

[GNRick]

I was thinking maybe a bad pump would only get to 53 psi, thus limiting boost to 10. Do you have more than 53 psi fuel pressure?

 

[mexburito]

Yeah it's at 60lbs.

 

[tallor]

Are you running Alky?

 

[rag231]

When you say it's at 60 what do you mean? If your base pressure is set to 43 vac off , at 10psi you should only see 53psi on the fuel gauge. How are you running the fuel gauge in the car? Electric or mechanical? I don't know how 100% accurate the mechanicals are with an isolator ( safety first) but I would have to have verification at the rail first, then compare it to your current gauge. You said in your post that the fuel pressure "seems" to be good.

 

[mexburito]

No just E85.

 

[johnplogii]

Sounds like fuel pump to me too.

 

[TurboBob]

make sure the positive battery cable is not grounding out.

Bob

 

[mexburito]

I had already checked all my grounds but I will check my positive cable . Thanks.

 

[V6sleeper]

Hotwire? check the connections behind the alternator.