Actual Values

[McCullough]

I'm just starting to use the Durametric to diagnose some occasional rich running conditions (strong exhaust smell).

Can someone help me understand what "Spec. Air Mass" and "Spec. Air Adaption" are? (What is "Spec.?") I'm getting somewhat high readings on "Mass Air Flow" and "Spec. Air Mass." I'm currently suspecting a slightly cracked oil fill tube.

-- Tom

[Loren]

Year and model of your car please?

The specs are different depending on that (i.e. egas, S vs. non-S, etc).

[catmanluge]

I would be interested in learning how a Durametric can be used to explore these areas? Any guidance would be helpful...

Thanks

[McCullough]

Year and model of your car please?

The specs are different depending on that (i.e. egas, S vs. non-S, etc).

The car is a '99 986 Boxster but it's got a '99 911 3.4L motor (non-egas). Heavily tracked.

I've got a list of all the DME Setpoints for the motor but I don't understand what the values for "Spec. Air Mass" and "Spec. Air Adaption" are. What is "Spec." an abberviation for? "Special?" "Specification?"

--- Tom

Edited September 17, 2008 by McCullough

[Loren]

Her are the "within" ranges for air mass (the air flow past the MAF)

Idle -- 12 - 24 ML in kg/h

No load, n=2500 rpm -- 40 - 70 ML in kg/h

Adaption values usually refer to mixture adaption - these are TRA and FRA

TRA: = Adaptation in area close to idle for cylinders 1 - 3

TRA2: = Adaptation in area close to idle for cylinders 4 - 6

FRA: = Adaptation under load for cylinders 1 - 3

FRA2: = Adaptation under load for cylinders 4 - 6

It might be good for you to pick one of the OBD II manuals from Sunset Imports - the 5.2.2 OBD II manual is only $55.

[amegarth]

Hi I have a 1997 Boxster tiptronic and I was looking at actual values with a Durametric tool and with engine warmed up at idle the Spec. Air Mass of 15.5 Kg/h seems normal but the Spec. air adaption reads -1.0 Kg/h and is not right as the manual says 1.5 is normal.

Any idea what can cause this?

[Loren]

Hi I have a 1997 Boxster tiptronic and I was looking at actual values with a Durametric tool and with engine warmed up at idle the Spec. Air Mass of 15.5 Kg/h seems normal but the Spec. air adaption reads -1.0 Kg/h and is not right as the manual says 1.5 is normal.

Any idea what can cause this?

 

I'm not sure what manual you are using but the here are the values from the DME 5.2.2 Porsche manual -- and you are right on.

 

(click to enlarge)

[amegarth]

 

Loren I observed -1.0 for the Spec air adaption with no change with rpm

 

Any idea what could cause this deviation from nominal.

 

I have been getting  fault codes P0410 and P1411 for the secondary air injection.

The pump runs ON STARTUP when the engine is cold then shuts off.

But the pump sometimes comes back on after driving when I come to a stop and idle.

This turns on the Check engine light sometimes.

I have changed the MAF and the O2 sensors.

They both look like they are operating normal on the Durametric Actual Values

[Loren]

The way your secondary air runs is normal.

Perhaps there is a leak or there is blockage in the lines?

I would treat the codes as they generally point to the causes.

[Ahsai]

This thread may help http://www.renntech.org/forums/topic/39927-p0410-and-p1411-running-out-of-ideas/?p=211436

[Richard Hamilton]

In answer to part of your original question, "Spec." is short for Specific.  ie a specific mass flow rate (Kg/hr) calculated from a volumetric flow (cu.m/hr) at standard conditions.