OBD Scan Tech Nissan Power Balance Works

[Infinitiguy19]

Today I installed a clean Auxiliary Air Control valve/Idle Air Control Valve and the Auxillary Air Control valve duty cycle went 30% down to a normal 10%. I last semi cleaned (Half a**) the AACv two years ago I think (Can't remember) but in that time it got fairly dirty I would say to climb so high. I cleaned the Throttle Body Last year and the EGR and the plenum is fairly clean (No build up in the EGR port on plenum).

So we can confirm that the intake is clean and I have no vacuum leaks not a big one at least because at idle I get 20" Hg (~650 RPMs).

Injectors are a couple of years old but I have no history of a BG power flush, just BG44K and Redline S1 along with ISO Heet.

I never did a compression test but the engine was rebuilt at 30K miles at a Infiniti dealer (Not back in Japan).

I never did a oil pressure test but on of the HLA's on the left bank possibly #7 cylinder is clogged and makes a noise. I have tried BG Quick clean thats put into the engine oil and run for 15 minutes a couple of times but thats has yet to fix it. I am worried about using Marvel Mystery Oil because I haven't heard many good things about it.

The spark plugs were changed last year with OEM NGK standard 5 heat range, Gap may or may not have been checked to make sure its correct. There is a leak on coil packs 1 and 2 but I need to make the time to reseal them, I have 8 used spare coil packs and one used harness for the right side. All the spares OHM to at least 7 OHM's and the spare harness has continuity to all connections.

Timing according the ECU seen through the Consult is set to 15* Before Top Dead Center.
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Enough about my car here is how to set up the power balance test so you get good results:

Start up OBD Scan tech (Nissan)-> Go to the Power Balance button on the bottom left of the screen-> Go to the Options tab->
Make sure the values on your screen match those below then press the "Save" button

(8 Cylinder)
(Under RPM Adjustment turn the dial all the way to the right till you see 200) (This is to hold the AAC wide open (100%))
(Cylinder off and cylinder stabilization should be bot 9 seconds). (From the default 2 and 3 seconds).
(You can check the "Power Balance" box but I am unsure if it makes any difference.

When all of the above is set then select "Save" then every time you open the program those setting will be used unless changed.


http://picasaweb.google.com/lh/photo/FP ... directlink


http://picasaweb.google.com/lh/photo/_c ... directlink

When the above is set correctly go to the main default screen by selecting the "Test Results" tab-> The select the "Start/Stop tab on the top right-> Press Start.

Let the test run then go to the "Summary" tab to see the result in detail.

The only thing I can't confirm is if the Injector pulse width changes to make up for the cylinder thats shut off.
I will do some tests tomorrow and see if it does or not.

Here are three back to back runs with the CD changer paused, Hood open, TCS off and doors closed:



------------------------------------------------------------------------------
Power Balance Test Summary On 8/10/2010 7:38:43 PM
Coolant Temperature: 185 Deg {F}
Idle Air: 100 %
Cylinder # 1
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1554 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1462 Rpm
Average RPM Drop Result... 92 Rpm
Highest RPM Drop... 854 Rpm
Amount Of Data Sampled When Cylinder Off... 569
Cylinder # 2
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1546 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1472 Rpm
Average RPM Drop Result... 74 Rpm
Highest RPM Drop... 846 Rpm
Amount Of Data Sampled When Cylinder Off... 567
Cylinder # 3
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1549 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1475 Rpm
Average RPM Drop Result... 74 Rpm
Highest RPM Drop... 849 Rpm
Amount Of Data Sampled When Cylinder Off... 572
Cylinder # 4
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1550 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1476 Rpm
Average RPM Drop Result... 74 Rpm
Highest RPM Drop... 850 Rpm
Amount Of Data Sampled When Cylinder Off... 549
Cylinder # 5
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1553 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1482 Rpm
Average RPM Drop Result... 71 Rpm
Highest RPM Drop... 828 Rpm
Amount Of Data Sampled When Cylinder Off... 569
Cylinder # 6
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1560 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1489 Rpm
Average RPM Drop Result... 71 Rpm
Highest RPM Drop... 822 Rpm
Amount Of Data Sampled When Cylinder Off... 570
Cylinder # 7
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1564 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1473 Rpm
Average RPM Drop Result... 91 Rpm
Highest RPM Drop... 839 Rpm
Amount Of Data Sampled When Cylinder Off... 567
Cylinder # 8
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1559 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1484 Rpm
Average RPM Drop Result... 75 Rpm
Highest RPM Drop... 821 Rpm
Amount Of Data Sampled When Cylinder Off... 569
------------------------------------------------------------------------------


------------------------------------------------------------------------------
Power Balance Test Summary On 8/10/2010 7:42:01 PM
Coolant Temperature: 185 Deg {F}
Idle Air: 10 %
Cylinder # 1
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1472 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1471 Rpm
Average RPM Drop Result... 1 Rpm
Highest RPM Drop... 734 Rpm
Amount Of Data Sampled When Cylinder Off... 561
Cylinder # 2
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1550 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1479 Rpm
Average RPM Drop Result... 71 Rpm
Highest RPM Drop... 825 Rpm
Amount Of Data Sampled When Cylinder Off... 569
Cylinder # 3
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1562 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1479 Rpm
Average RPM Drop Result... 83 Rpm
Highest RPM Drop... 862 Rpm
Amount Of Data Sampled When Cylinder Off... 569
Cylinder # 4
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1558 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1480 Rpm
Average RPM Drop Result... 78 Rpm
Highest RPM Drop... 858 Rpm
Amount Of Data Sampled When Cylinder Off... 565
Cylinder # 5
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1554 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1471 Rpm
Average RPM Drop Result... 83 Rpm
Highest RPM Drop... 829 Rpm
Amount Of Data Sampled When Cylinder Off... 569
Cylinder # 6
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1548 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1466 Rpm
Average RPM Drop Result... 82 Rpm
Highest RPM Drop... 823 Rpm
Amount Of Data Sampled When Cylinder Off... 571
Cylinder # 7
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1553 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1456 Rpm
Average RPM Drop Result... 97 Rpm
Highest RPM Drop... 828 Rpm
Amount Of Data Sampled When Cylinder Off... 502
Cylinder # 8
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1538 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1460 Rpm
Average RPM Drop Result... 78 Rpm
Highest RPM Drop... 813 Rpm
Amount Of Data Sampled When Cylinder Off... 496
------------------------------------------------------------------------------


------------------------------------------------------------------------------
Power Balance Test Summary On 8/10/2010 7:45:18 PM
Coolant Temperature: 185 Deg {F}
Idle Air: 10 %
Cylinder # 1
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1477 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1456 Rpm
Average RPM Drop Result... 21 Rpm
Highest RPM Drop... 752 Rpm
Amount Of Data Sampled When Cylinder Off... 558
Cylinder # 2
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1540 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1474 Rpm
Average RPM Drop Result... 66 Rpm
Highest RPM Drop... 815 Rpm
Amount Of Data Sampled When Cylinder Off... 541
Cylinder # 3
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1537 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1472 Rpm
Average RPM Drop Result... 65 Rpm
Highest RPM Drop... 837 Rpm
Amount Of Data Sampled When Cylinder Off... 564
Cylinder # 4
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1548 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1467 Rpm
Average RPM Drop Result... 81 Rpm
Highest RPM Drop... 823 Rpm
Amount Of Data Sampled When Cylinder Off... 484
Cylinder # 5
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1559 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1485 Rpm
Average RPM Drop Result... 74 Rpm
Highest RPM Drop... 821 Rpm
Amount Of Data Sampled When Cylinder Off... 566
Cylinder # 6
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1561 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1484 Rpm
Average RPM Drop Result... 77 Rpm
Highest RPM Drop... 836 Rpm
Amount Of Data Sampled When Cylinder Off... 570
Cylinder # 7
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1555 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1479 Rpm
Average RPM Drop Result... 76 Rpm
Highest RPM Drop... 830 Rpm
Amount Of Data Sampled When Cylinder Off... 563
Cylinder # 8
Cylinder On Stablized For 9 Seconds
Average RPM When Cylinder Stablized... 1557 Rpm
Cylinder Off Sampled For 9 Seconds
Average RPM When Cylinder Is Off... 1484 Rpm
Average RPM Drop Result... 73 Rpm
Highest RPM Drop... 832 Rpm
Amount Of Data Sampled When Cylinder Off... 570
------------------------------------------------------------------------------

[Lokim]

I never did a oil pressure test but on of the HLA's on the left bank possibly #7 cylinder is clogged and makes a noise. I have tried BG Quick clean thats put into the engine oil and run for 15 minutes a couple of times but thats has yet to fix it. I am worried about using Marvel Mystery Oil because I haven't heard many good things about it.

I had an HLA noise on the passenger bank of my 94. I poured about a cup of MMO in and drove like a grandma for a week. About two days into it, the noise went away. I changed the oil after the week was up and haven't heard a tick since!

Don't believe the hype... MMO is fine, IN MODERATION!

[Infinitiguy19]

If it comes down to it I will go that route but I only have 2K miles on M1 0W-40 oil. I will change in 4K miles because It feel weird going so long between a oil change.

[OwnerCS]

I never did a oil pressure test but on of the HLA's on the left bank possibly #7 cylinder is clogged and makes a noise. I have tried BG Quick clean thats put into the engine oil and run for 15 minutes a couple of times but thats has yet to fix it. I am worried about using Marvel Mystery Oil because I haven't heard many good things about it.

I had an HLA noise on the passenger bank of my 94. I poured about a cup of MMO in and drove like a grandma for a week. About two days into it, the noise went away. I changed the oil after the week was up and haven't heard a tick since!

Don't believe the hype... MMO is fine, IN MODERATION!

Cool thread!

MMO seems to be widely used for this purpose around the WWW. Back when I was a youngster (14yo) , working weekends and summers at a local "full service" station, the Chevrolet 265 V8 (55 & 56 models) and first generation Olds V8s, seemed to have chronic hydralic lifter noise problems. We would add a quart of Rislone with an oil change. On many occasions it would loosen up a stuck lifter and remedy the ticking noise. Those early Chevy V8s seemed to have a short life and most people replaced them with a 283 from the 57 through 67, or a 327 from 62 through 69 instead of overhauling the 265.

[Infinitiguy19]

I spent about 20 minutes trying to find a package that allows the OBD Scan Tech Nissan Consult software to talk to you and also receive voice commands:

You can download it here and for this version of OBD Scan Tech Nissan below its actually needed:
http://dl.dropbox.com/u/146957/SAPI4SDKSUITE.exe

Here is what I think is the latest OBD Scan Tech Nissan: http://dl.dropbox.com/u/146957/ScanTechNissan2.zip

Install OBD Scan Tech Nissan first then the voice package second.

The run the software with the above directions and make sure your car is at least at 176*F, Then post up some numbers!

[Infinitiguy19]

Cool thread!

MMO seems to be widely used for this purpose around the WWW. Back when I was a youngster (14yo) , working weekends and summers at a local "full service" station, the Chevrolet 265 V8 (55 & 56 models) and first generation Olds V8s, seemed to have chronic hydralic lifter noise problems. We would add a quart of Rislone with an oil change. On many occasions it would loosen up a stuck lifter and remedy the ticking noise. Those early Chevy V8s seemed to have a short life and most people replaced them with a 283 from the 57 through 67, or a 327 from 62 through 69 instead of overhauling the 265.

283's, 350's and 454's are great engines and hard to kill, I know a guy who wants one in his truck.

Rislone got sued I think right?

Well I just checked the injector pulse width and it does seem that when a cylinder is shut off the pulse width does go from ~2.17 all the way up to 2.40 as a max then slowly goes down to ~2.24--2.30.

So if someone can make a Power balance program that holds the Injector duty cycle at preciley 2.2 miliseconds, timing at 15* BTDC and make sure the AAC is open 100% during the test then we will have a working power balnce test. But this one is okay for now I think. But I don't mind being proved wrong because after all more fuel is added to the other cylinders when the cylinder being tested is shut off.

[Infinitiguy19]

You can't stop the ecu from trying to compenstate for rpm changes [without a Consult] as it will try to vary the IAC first, if that doesn't work it will change ignition timing, if that doesn't work it will change the fuel injector pulse width.

The ecu job is to try to hold the idle speed steady!!!!!!!!!!!!!!!!!!!

The Power Balance locks the IAC open [why the jump to 1,000-1,300 rpm fot the test*] and freezes ignition advance and injector opening time to 2.2 msecs.........

* the NEW base rpm is a good indication of how clean the intake, IAC passages, and injectors are


For example when AC is turned on the HVAC sends a signal to ecu to get ready get set NOW add 0.3 millisecs of injector time to what ever the previous calculation was, same when power steering is turned [it varies with speed].......the ecu also monitors the battery voltage to injectors to compensate for lights heater defroster, power windows, etc............even a 0.1 volt change at the injectors MUST BE COMPENSATED FOR.

OBDII monitors fuel temperature and another dozen parameters to get the injection pulse as perfect as it can be

Q45Tech

power-balance-test-t10804.html

The Consult reports OK IF all cylinders contribute something!

Any rpm drop other than ZERO!

This does not mean anything other than the cylinder is not completely dead...........negative numbers are possible due to the friction of a dead cylinder being less when the fuel is shut off!


All power balances should show the exact same rpm drop, if they don't - redo the test twice and average the results.
If the deviation is still more than 12-25 rpm you have problems!

Watch out for weird numbers that don't make sense..........sometimes the coolant temp varies [still warming up].....the test should wait until 3-5 minutes after you reach 176F watching that the temp doesn't continue to climb.

In practice something greater than a 25 rpm variance is feelable as an idle shake and 50-62 rpm is really noticeable.................not unusal to see Q come in with 50-75 rpm variance or even 100 rpm. 95% can be cleaned up to spec unless the rings are worn or the valves are leaking or the injector is really bad.

A cylinder has to be almost dead to notice much at high way speed...........after all each contributes only 12.5% of total power.

You could dyno the engine and it would only be 30-40 HP off [higher due to negative power to move the dead piston] and that might only affect the acceleration by 0.3-0.5 second.

Q45Tech

need-help-with-diagnostic-results-t21672.html

"The speed was held constant on a flat road, but the rpms went from 2000 to 2100 and back to 2000 in intervals of maybe 15 seconds while holding that speed"

I have to trust that the owners is holding the accelerator perfectly steady.........some people unkowingly tap dance ........why you take a test drive and watch the driver and read the TPS voltage while watching the rpm........with Consult.

When you do a power balance at 1200-1400 rpms [no load a dead cylinder will only drop the rpm 60-100 rpms] engine has enough interia and power.................so at 2,000 rpm?

Q45Tech

91-q45-engine-rpm-drop-t39813.html

The Consult and engine ecu is very dumb without a brillant technican to interprete the results.

The Consult say ok as long as something is happening or as long as the sensor signals are not zero or 5.0 volts....[some where in between].......it is just a window thru which you see what's happening.

Dealer techs learn from years of seeing the voltages at idle and cruise conditions to know what is right and wrong.

Unless a technican has taken the time to monitor WOT accelerations and record reems of data they don't know what is right and what is wrong under these conditions.

As to the MAF it just measures air flow and the air flow should be the same at specific throttle positions [10-100%] and rpm [within 10% for dirty intake track/valves, etc. Vacuum leaks can throw the numbers off at low to cruise rpm when the air flow is only 10-15% of maximum.

MAF voltage must be very very close to 1.22 volts [1.15-1.3 volts] at the right idle rpm when at operating temperature.

If not we swap the MAF and monitor the results for changes [bad MAF].

These engines are not complicated as very few sensors, the same as all others of the era. Failure to diagnose correctly indicates a defect in the technican!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Q45Tech

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Not Power Balance topic but came up on my search....good read anyway:
you-are-invited-to-a-discussion-about-s ... 02471.html

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If you can develop an accurate tachometer that can resolve 12 rpm* out of 1200 rpm, disconnect IAC solenoid, tweek IAC manual bypass so rpm goes up to 1200 rpm and build 8 push botton that interrupts EACH injector lead going to ecu. You can manually do a power balance.

*the hard part to achieve 1% resolution

Q45Tech

power-balance-t401146.html

Mini Rotor Rooter [made from old throttle cable] and drill.........remove EGR valve assembly first.

Q45Tech

94-q45t-cold-start-idle-problem-t363501.html

So anyone else have any power balance reports?