Any ideas??

madman1234509 · Jun 14, 2013

Would you need to rescale the maf, or would you need an aftermarket maf to read higher? Also what abount a resistor or something wired into the maf, is that a posibilty if tuning isnt available yet?

mike@haller's · Jun 14, 2013

usually just rescaling the maf is fine. theyre are some mafs for duramaxs that have a switch to change what the computer is seeing. but the ones I worked with were a pain and ended up getting pulled off and just rescaled the sensor

Kind · Jun 14, 2013

mike@haller's said:
They are capable of reading to 95psi. The issue is the factory only allowed for that high. so the number becomes skewed and inaccurate after 37psi. Thats why dustin designed his boost harness for the dash daq. it uses factory map sensors but will accurately display the number on the dash daq. it also comes with two sensors for reading low pressure and total boost.

I have that. Still trying to to find the signal in my old style dashdaq.

mike@haller's said:
rescaling the maf on a duramax is a must if it has a larger intake. if you don't it gets a lazy throttle since it doesn't see all the air coming in. it also bases the load of the motor of the maf, which affects transmission operation.

That seems to be what mine is like past 20% throttle.

I just don't get why it would make peak frp up to that amount of throttle then instantly drop 13k... If it was a fuel supply issue would it not gradually, maybe even rapidly decline... Not necessarily instantly drop... Or even make peak frp in the first place?

madman1234509 · Jun 14, 2013

Probably hitting it max, freaking out and defueling or something since it cant tell how much air is coming in.

mike@haller's · Jun 14, 2013

Kind said:
That seems to be what mine is like past 20% throttle.

I just don't get why it would make peak frp up to that amount of throttle then instantly drop 13k... If it was a fuel supply issue would it not gradually, maybe even rapidly decline... Not necessarily instantly drop... Or even make peak frp in the first place?

It shouldn't affect rail pressure as far as I know. Only the commanded mm3 being injected into the motor. Do you have dual pumps or an industrial pump? what size nozzles do you run, what lift pump do you run and what kinda pressure are you running the lift pump at?

Kind · Jun 14, 2013

mike@haller's said:
It shouldn't affect rail pressure as far as I know. Only the commanded mm3 being injected into the motor. Do you have dual pumps or an industrial pump? what size nozzles do you run, what lift pump do you run and what kinda pressure are you running the lift pump at?

Single II HPFP, Elite 110's, Airdog 165. Airdog is set with adjustment screw all the way in and regulated by the Elite fuel bowl delete. I don't have a gauge yet to know exactly what my low pressure is at. It was just yesterday I adjusted the Airdog to max... I hadn't noticed any difference.

mike@haller's · Jun 14, 2013

Kind said:
Single II HPFP, Elite 110's, Airdog 165. Airdog is set with adjustment screw all the way in and regulated by the Elite fuel bowl delete. I don't have a gauge yet to know exactly what my low pressure is at. It was just yesterday I adjusted the Airdog to max... I hadn't noticed any difference.

Well even if the airdog is maxed, the regulator on the fuel bowl delete could be bypassing it all. get a gauge on it and set the regulator to 15psi. the industrial should maintain 110s fine even with a huge pw. have you checked also for high pressure fuel leaks into the crankcase? such as the injector lines or rails leaking internally? if they are leaking your crankcase will fill up pretty quick which is easy to check on the dipstick. check your regulator first then I would look around for leaks.

Kind · Jun 14, 2013

mike@haller's said:
Well even if the airdog is maxed, the regulator on the fuel bowl delete could be bypassing it all. get a gauge on it and set the regulator to 15psi. the industrial should maintain 110s fine even with a huge pw. have you checked also for high pressure fuel leaks into the crankcase? such as the injector lines or rails leaking internally? if they are leaking your crankcase will fill up pretty quick which is easy to check on the dipstick. check your regulator first then I would look around for leaks.

Checking for fuel in the oil was one of the first things I did.

A gauge is something I will get in the next day or so if I can find one in my town.

Matt · Jun 14, 2013

Some more under hood pics would definitely help also.

Kind · Jun 14, 2013

Matt said:
Some more under hood pics would definitely help also.

I suppose... Pretty hard to diagnose the issue without proper incentive.

Trips by kind325, on Flickr

Erikclaw · Jun 14, 2013

Looks good, but a piping nightmare. LOL

Jeremysmith9902 · Jun 14, 2013

mike@haller's · Jun 14, 2013

Kind said:
Checking for fuel in the oil was one of the first things I did.

A gauge is something I will get in the next day or so if I can find one in my town.

Let me know what you find. Ive found after many years, that checking and fixing your basic stuff will usually fix the problem or make it stick out even bigger.

Kind · Jun 14, 2013

Erikclaw said:
Looks good, but a piping nightmare. LOL

It was a nightmare for Jordan to figure all out... But it takes only a few minutes and everything can be removed.

Jeremysmith9902 said:
NICE

Thanks!

mike@haller's said:
Let me know what you find. Ive found after many years, that checking and fixing your basic stuff will usually fix the problem or make it stick out even bigger.

Will do...