klpps

Hey guys,
I scanned my computer today and got all sorts of data but i have no clue how to interpret them. I was wondering if someone wouldn't mind chiming in and tell me if everything looks normal or not. My car is a 97 but has been converted to an OBD-1 by madwolf. Here is some of the data i pulled when pulling into the parking lot after driving for about 30 minutes. The car was parked and idling.

Loop was closed

Learned Idle Position - 17 steps
Idle Air Meter position - 20 steps
Spark Advance - 23 degrees
Knock Retard - 0
Knock Sensor - 69
Block Learn Cell - 16
Black learn values were all very near 128
Left and right o2 sensors fluctuated from very low mvolts to 700+ mvolts
A/C Pressure - 1.29 psi
MAP sensor - 1.23 V
Injector Pulse - 2.9 ms
MAF 5 gr/s
Throttle Sensor - .58V
Desired RPM - 650
Also, when I'm in park, my engine RPM shows to fluctuate from 575 - 700. Is this normal? Should it be smoothe at 650 RPM?
Any help would be greatly appreciated.

Makaveli

do a search for posts by Injuneer

he has a whole writeup on scanning software and what all those numbers mean, its very imformative

Injuneer

You might want to check this document, it should answer some of your questions:

http://members.aol.com/InjuneerZZ/ScanMast.htm

Learned Idle Position - 17 steps
Idle Air Meter position - 20 steps

This is the IAC motor position command. The PCM has "learned" that it takes 17 steps fo the IAC "stepper" motor to give you the correct idle speed. At the particular
moment you scanned it, the PCM was telling the IAC to move to 20 steps. There is no feedback to tell the PCM if the IAC motor is actually at that position. Anythihng from 15-40 steps is "normal".

Spark Advance - 23 degrees

Normal. That's the spark advance the PCM picked off the timing map, based on RPM and MAP.

Knock Retard - 0

Normal. You aren't getting any knock retard.

Knock Sensor - 69

This is a cu,ulative count. It increments up under some knock conditions. A single static "snapshot" tells you nothing. You need to see if the count is increasing at any point in time.

Block Learn Cell - 16

Read my writeup to understand what the long term fuel corrections do, and how the Cells are arranged. Cell 16 is the normal cell used for idle.

A/C Pressure - 129 psi

Pressure in your A/C discharge. Whether its normal depends on what the A/C was doing at the time.

MAP sensor - 1.23 V

Normal. I'll have to check the conversion from volts to kPa, but I think its correct.

Injector Pulse - 2.9 ms

Injector pulse width in milliSeconds. Maybe a shade on the high side for idle conditions. You should have one pulse value for the left bank, and another for the right bank.

MAF 5 gr/s

This is the mass air flow in grams per second. A little on the low side, particularly with the 2.9mSecond pulse width.
Throttle Sensor - .58V

Desired RPM - 650

Normal programmed idle speed for an A4 in neutral. This is what the PCM is trying to maintain, not the actual RPM.

Also, when I'm in park, my engine RPM shows to fluctuate from 575 - 700. Is this normal? Should it be smoothe at 650 RPM? Any help would be greatly appreciated.

Its fairly normal to see the idle range from +/- 25rpm... or 625-675. Yours seems a little on the high side in terms of variation. Not idling as smoothly as it should.

A single record from a scanner isn't real useful. And, there are a lot more things you need to look at.

klpps

would the fluctuation in idle RPM be caused by a vaccum leak maybe? fuel pressure problem? should i be worried about the injector pulse? the link does not work =(