Error On Cylinder Balance Test

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Re: Error On Cylinder Balance Test

Postby DebbieSidera » Sat Dec 07, 2013 5:49 pm

Hi Kim,

I really wouldn't like to confuse you. I described two different cars with two very different problems. The F360 it was running lean. The code p1160 appears for running lean. Now the car is running normal.... but it had a very difficult starting in cold. Then the problems just disappear. I have been checking ignition and injection system, everything looks just fine. I personally drove the car several times and the code disappear too. But on the freeze data still a 22% for the long term fuel trim. And NO, I didn't check the oxygen sensors yet. Thanks Kim I would love to follow your directions. Here in California the cars have even a way more complex smog system... and the car importers used to adapt aftermarket parts on them.


The misfire codes on the F456 (both banks) were stored on the memory with a bunch of another related codes...
Yes, the F456 runs with the Motronic M5.2. The car came from another shop and after the car was seating for several years, the owner had been trying to jump the battery for his own too... So, I don't want to pay to much attention on the stored codes.
I really liked the test results that I get yesterday with the pico. The ignition timing looks Ok but as you can see the compression events were not coordinate. But I'm still don't understand the whole thing;
-If the cams are wrong in 1-to-6 bank, why the car starts with any individual bank? I tried to pull the Motronic relay on each bank. They sounds about the same (crappy of course).
-Why I get a such of great compression readings with my regular gauge? they are about the same in both banks, so why the compression events are not coordinate on the relative compression test?

Thanks
Debbie
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Re: Error On Cylinder Balance Test

Postby mastertech02 » Sun Dec 08, 2013 12:32 am

Hi Debbie.
I have taken a look at the relative compression wave forms you have posted and they interest me due to the fact that some years back i was fortunate enough to have built a number of 456GT,s and 550 Maranello specials . I am also aware that the valve clearance setting and cam belt replacement procedure need care and attention to ensure they are correct.

The wave forms from my interpretation using the rulers and filters indicate to me that the ignition event on bank 1 is ocuring 6deg ATDC approx.

I have also looked at the compression events using rulers and the period between events is constant although the wave form visually looks as though there is a different time period between comression events. I have measured 60deg between events .

The difference that can be seen is the difference in current between TDC and BDC and measured is only approx 10amps if I am correct although visually looks a big difference.

I would check the cam timing as you suggested as i have seen how easily this can be set incorrectly and even jumped when engine turned against rotation.

Good work and will be good to see the result.

Also the WPS sensor is a Pico pressure transducer that can measure acurately cylinder compression and show valve events and timing accurately especially if sych to ignition event.

Regards
Dennis carey
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Re: Error On Cylinder Balance Test

Postby Fat Freddy » Sun Dec 08, 2013 3:15 am

Hi Debbie.

Sorry about my English. What is a WSP?


Your English is fine.
A WPS is for measuring in cylinder pressures to calculate cylinder leakage and valve events on a running engine as Dennis has pointed out. Usually I would use the crank sensor along with the transducer as a reference to rotation. Then compare to the companion cylinder. So in your case would be 1 and 6.
It would have helped confirm your suspect timing problem.

If you pay attention on the waves they look almost like a M and then there is a long period without compression. During this period the waves look like a V.


It sure doesn't look right. Certainly worth checking the timing. WPS for Xmas perhaps? :wink:

The reason I asked for the extended crank was to see if the higher cranking Amps on cyl 4 is consistent. Which it is. Not related to your problem and possibly nothing, just worth noting.


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Re: Error On Cylinder Balance Test

Postby Fat Freddy » Sun Dec 08, 2013 3:21 am

As Kim said check output from the Oxygen sensor, almost always worth doing with fuelling problems. Also check the sensors reaction - force rich and lean to check reaction.

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Re: Error On Cylinder Balance Test

Postby mastertech02 » Sun Dec 08, 2013 12:39 pm

Hi Debbie.
Is it possible for you to capture a Bank 1 cam/crank wave form synch to No 1 cyl ignition and a Bank 2 cam/crank wave form sych to cyl No 12 ignition.
Hopefully you can compare the two banks to see if cams are out or at least the cam ref for the sensors.
There is a chance that both banks are out if the crank position was out when cam belts replaced.

Away from trying to diagnose via scope. Does the engine only run rough cold idle ? Is there an improvement if RPM increased.

How long had car been sitting ? Has fuel been replaced and injector cleaner added ?

Relative compression only a guide and you have backed up with manual check with no notable cylinder.
Running compression with WPS would be ideal as losses through valves /rings may show at idle especially during low cylinder fill through closed throttle and idle valve as fill time is reduced at idle compared to cranking.

Regards
Dennis Carey
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Re: Error On Cylinder Balance Test

Postby Robski » Sun Dec 08, 2013 1:47 pm

Is it possible for you to capture a Bank 1 cam/crank wave form sync to No 1 cyl ignition and a Bank 2 cam/crank wave form sych to cyl No 12 ignition.
Hopefully you can compare the two banks to see if cams are out or at least the cam ref for the sensors.


The engine only has one cam sensor and for the ignition timing has two crank sensors on the flywheel


Running compression with WPS would be ideal
agreed.
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Re: Error On Cylinder Balance Test

Postby DebbieSidera » Mon Dec 09, 2013 3:58 am

Hi guys!

Thanks to educate me with the Picoscope.

Dennis,
Is it possible for you to capture a Bank 1 cam/crank wave form synch to No 1 cyl ignition and a Bank 2 cam/crank wave form sych to cyl No 12 ignition.
Hopefully you can compare the two banks to see if cams are out or at least the cam ref for the sensors
.

Well, Could I see any difference between the Bank 1 crank sensor and the cylinder #01? I mean we already know that the ignition spark events are ok since there is the same period of time between them, right? I would really like to perform the same test on the cam sensors but this engine only has one sensor in the exhaust cam on the bank 1-to-6. Anyways I'll make this test tomorrow. Yes, I drained the old fuel.

Fat,
It sure doesn't look right. Certainly worth checking the timing. WPS for Xmas perhaps?

Oh, I didn't know that you guys call WPS for the transducer device. It will be my own Xmas present for sure!! Any recommendations? I saw that some guys are using the Fluke one. It cost about the half price of the Pico one. Of course the Pico one looks so cool and goes to 500Psi.

Note: I'm working in this car for my own at night. I can't take the engine apart to check the cams yet. I don't want to get involve with any of my company business with this car. The owner is considering the car value since the car need a bunch of work such transmission, upholstery, paint,... and now the car just seats at the corner of my shop. I'm just learning to use my Pico and perhaps help the car owner.
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Re: Error On Cylinder Balance Test

Postby tkazadzis » Mon Dec 09, 2013 4:55 pm

I have the same issues, unable to get a reading on a 2000 BMW X5. I followed all the steps and also I am getting a bright green 100% signal and sometimes a light green 100%, once I click START it flickers a few times with erratic green bras going up and down and then nothing happens.
I have tried with full loads the battery voltage indicates 13-5 - to 13.9 volts and thus far I am unable to make it work.
When I click START I have good voltage, 100% signal, 8 Cyl. ( Probe on this vehicle is connected on drivers side engine firewall) battery is in trunk bellow spare and alternator P is almost impossible to reach)
Please Has anybody else had this issue and what's the solution? :?
Theo
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Re: Error On Cylinder Balance Test

Postby DebbieSidera » Mon Jan 27, 2014 1:52 am

tkazadzis wrote:I have the same issues, unable to get a reading on a 2000 BMW X5. I followed all the steps and also I am getting a bright green 100% signal and sometimes a light green 100%, once I click START it flickers a few times with erratic green bras going up and down and then nothing happens.
I have tried with full loads the battery voltage indicates 13-5 - to 13.9 volts and thus far I am unable to make it work.
When I click START I have good voltage, 100% signal, 8 Cyl. ( Probe on this vehicle is connected on drivers side engine firewall) battery is in trunk bellow spare and alternator P is almost impossible to reach)
Please Has anybody else had this issue and what's the solution? :?
Theo


Hi tkazadzis,
In my opinion, you should forget about the Pico Diagnosis software... I mean it work in simple engines, but I never had a successful test on V8 or V12 engines. I'm still learning about this software but in my short experience DOESN'T WORK. I'm using the oscilloscope and then I'm reading the waves.
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Re: Error On Cylinder Balance Test

Postby DebbieSidera » Mon Jan 27, 2014 3:07 am

Hi guys,

I had been out of the F456_GTA project for a while and I only I've been working non-stop on another project for the Cavallino show.
As I told you I was only working on the F456 for my own pleasure but... too late! the car is not at the shop anymore. The owner took the car to another Ferrari dealer to get a second opinion of the problem.
I read a fax, they said that the whole problem is base on the #11 injector.
Well, I never had the chance to check one by one the injectors out of the engine. So maybe the 11th is physicality clotted? I don't know how they performed the test either, but I know that all the injectors had signal since I checked each of the connector terminals of the injector harness. Also I used my ohmmeter in all of the injectors and the resistance were the same in all of them (between 15 and 16 ohms).
I was laughing when I knew that they were focus on the 11th injector after all my reading in the 1 to 6 bank. The oscilloscope showed clearly that the timing was not right on this bank but since I never performed the test with a transducer I'm still confuse and maybe they are right. What it could have been lying to my oscilloscope? If the timing is correct why it shows that the spark event happens before TDC?
On the other hand, I know very well that they can not be right because if you disconnect the injection or ignition in only one of cylinders on a V12 engine, the difference of a sound it is almost imperceptible. This engine sounded terrible!
I hope that the car comes back to my shop, because even if its for my own interest I would like to finish this puzzle.
NOTE: I found a used Fluke PV350 transducer for 150$, do I should take it? I was thinking to save some money to buy the Pico one but is a very attractive price.

Thanks again for all your support!
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