Throttle Body balancing

Not sure why Davida does that except it does allow the 5mm very long stubs to be screwed into the 6 mm stubs. But if you want to fit them permanently (rather than lose them in the back of garage), the thread allows you to put a 5mm bolt in and ride around as usual. Also means you can spend longer checking balance as you can ride around normally between checking with gauges. The £4.80 is replacements; originals came with the kit....

OK, I guess I am just old and thick headed but I cannot for the life of me determine what hose I need to remove to do the TB Balance.  Beetle showed me a pic from this thread but still I can't figure it out.

So here are two pictures, is either one of these hoses the one I need to remove, or is it another.  I need to get this done on my new  to me GRiSO.  Thanks

Is it this hose:

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Or this one or another entirely  

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It'll be the first one, the second is the injector body..... Guess with US variants there are more vacuum returns for emissions re-cycle so you get the braided pipe and connector as well.

cognosticator wrote:

OK, I guess I am just old and thick headed but I cannot for the life of me determine what hose I need to remove to do the TB Balance.  Beetle showed me a pic from this thread but still I can't figure it out.

So here are two pictures, is either one of these hoses the one I need to remove, or is it another.  I need to get this done on my new  to me GRiSO.  Thanks

Is it this hose:

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Or this one or another entirely  

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The one in the first photo is the one, you need to remove the bolt from the throttle body on both cylinders and screw in the adapters to connect the hoses that come with your Carbtune or whatever you are using to balance the TB's.

The injector is what you are pointing to in the second photo, do not touch that!

Apologies, Paul has already set you on the right track,

Thanks guy I really appreciate the help.  I just wanted to be sure.  

This will make it a snap, I am going with a Beetle map, then do the rest, TB sync, reset TPS  etc.

I am in the middle of changing tires on her, the original ones are flat spotted and scary when turning in a tun, the new Pirelli Angle GT's will feel great once I get her all buttoned up.

I'm guessing just put connector instead of screw 10. Evap circuit will then be shut-out

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Ahh. I was confused by your green moniker. If it had been blue, I would have told you that you had an evap canister attached. My apologies!

Thanks for all the help, today I got Beetles map installed, synched the TB's, reset TPS and Adaptions and now it is raining and suppose to all day damnit.

I can tell the bike starts and idles like it should have, not rough and coughing like it was.

Thanks again for a great community

Want to be sure that I have the correct screw to adjust the bodies at 3500 rpm - per the attached photo it must be the one facing the camera as the other one sitting sideways is not touching anything at half throttle, which is where I have it opened to.  I do not want to touch the "sacred screw."

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Correct.

Pete Roper wrote:

Choose 'Actors', follow the prompts and do a TPS re-set, then go back to 'Measurements' and the TPS reading should flick to 4.6 for an 1100/1200 2VPC bike and 4.8 for a 4VPC machine. Pete

Hi Pete and Mark...

I've done the Throttle body balancing as described here (read it 3 or 4 times before hand to make sure the sequence is known properly before diving in), and checked all parameters with GuzziDiag. I am constantly seeing a 4.60 reading on the throttle body on my 2015 8V GRiSO...can't ever see it at 4.80. Have gone thru the procedure several times resetting TPS, Auto Learning Parameters and still no luck.

Even loaded a new 2018 map from Beetle, did the whole procedure again and still getting 4.60.

So...stupid question..how do I adjust the throttle body parameter to get it to 4.80, if possible?

Thanks both!
Paul

No need. 4.6 is OK. It can be 4.6/4.7/4.8.

beetle wrote:

No need. 4.6 is OK. It can be 4.6/4.7/4.8.

Excellent!! Thank you Mark!!

Took it for a ride today, put a 100 miles on with my friends Tom on his Stelvio, and stunned to see a 44 mpg result after today’s ride. I had been seeing 38 to 39 regularly on the dash display. It this is amazing. Smooth, no flat spot and rides beautifully!

Hi , I am having a trouble with thottle balancing of my Stelvio.I did it before three times with success and bike was always running better after balancing but now it is not good. The problem is that fuel mixture is too lean. The idle is unstable at low engine temperatures and above 80°C is stalling very often. Also it is poping in exhaust when close throttle at medium RPM.
I have tried this: Clean throttly body, valve of steper motor and injectors in ultrasonic cleaner perfectly. Than changed spark plugs, air filter and finally TPS. The throttle body is balanced perfectly without noticable pressure different between L and R cylinder. I also checked compression pressures in both cylinder on warm engine - both are the same 12,2bar. The sacred screw has never been touched as well as the linking rod.
I check the spark plug color after few miles and both are incredibly clean indicating lean mixture. Do you have any advise?

Jan

bar1976 wrote:

Hi , I am having a trouble with thottle balancing of my Stelvio.I did it before three times with success and bike was always running better after balancing but now it is not good. The problem is that fuel mixture is too lean. The idle is unstable at low engine temperatures and above 80°C is stalling very often. Also it is poping in exhaust when close throttle at medium RPM.
I have tried this: Clean throttly body, valve of steper motor and injectors in ultrasonic cleaner perfectly. Than changed spark plugs, air filter and finally TPS. The throttle body is balanced perfectly without noticable pressure different between L and R cylinder. I also checked compression pressures in both cylinder on warm engine - both are the same 12,2bar. The sacred screw has never been touched as well as the linking rod.
I check the spark plug color after few miles and both are incredibly clean indicating lean mixture. Do you have any advise?

Jan

Jan, are you running the original map and did you reset auto learning after resetting the TPS.
Did you check if one of the HT leads is damaged and sparking to earth.
It might be worth temporarily blocking off the hose from the air box to the stepper to see if the problem is still there when the engine is warm. It will still want to cut out when cold. A few shots of carb cleaner into the stepper hose has helped some people’s idle problems.
Best of luck finding the problem

Yes I have reset TPS and autolearning parameters. I also changed boths spark plug connectors and leads. Hoses and also steper motor valve hav been cleaned in ultrasonic cleaner and I also checked the function of stepper in GuzziDiag. The bike was running more than a year a map from Mark and it was very very good. Now I had to go back to factory map because this map run in close loop control of Lambdas and it compensate lean mixture little bit now. I still don´t know what can be the problem. The issue appeared when I remove the engine from bike due to change of clutch. After assembling engine back the running is poor. I double chacke also al hose connection and wire connections but no any findings. Maybe it could be some air leak on intake side. Note: the bike is 2012 with roller cams from factory. I also checked the valve cleareance, it is 0,1mm and 0,15mm.

Sounds like an intake leak. Make sure the rubbers are good & clamps are tight between throttle bodies and intake manifolds. Make sure there are no cracks or leaks in hose that connects L & R intake manifolds. Did you check the O2 sensor parameters, is it working correctly? Did you shut it off in the map before going to a Beetle map and not turn it back on when installing the map back in?
Another thing, is your cat in the muffler plugged up? Just an idea.

Use GuzziDiag to check your sensor values are good. Air temperature, engine temperature, pressure etc.

mine did the same after clutch change - engine out engine back....
turned out the problem was one of the injectors was partially blocked with gunk that I 'relocated' when cleaning the manifolds.
check them too!

All sensors seem to be OK. I going to remove again stepper motor to check tightness of valve and the hoses for cracks. What about a low pressure of fuel pump? Blocked fuel filter? Sombody told me that also broken catalyser in muffler can have similar symptoms.

Hi,

finally I had time to check the stepper motor. I disconnected hoses between idle stepper controled valve and throttle bodies and blinded the holes in throttle bodies. Then I again balanced the bodies and reset TPS and autolearning params. Now the bike is running as a new one . Idle is stable, throttle response is quicker ( especially the RPM fall down very quickly when closing the throttle, no misfireing.) I also reflash the map with Beetle´s map and now it is working fine as before. Spark plug color turned back to normal after few miles ride . Now I will remove the idle valve from bike and will do some test on it. I want to know if it is closing perfectly.

bar1976 wrote:

Hi,

finally I had time to check the stepper motor. I disconnected hoses between idle stepper controled valve and throttle bodies and blinded the holes in throttle bodies. Then I again balanced the bodies and reset TPS and autolearning params. Now the bike is running as a new one . Idle is stable, throttle response is quicker ( especially the RPM fall down very quickly when closing the throttle, no misfireing.) I also reflash the map with Beetle´s map and now it is working fine as before. Spark plug color turned back to normal after few miles ride .  Now I will remove the idle valve from bike and will do some test on it. I want to know if it is closing perfectly.

Great stuff bar1976 Am I understanding correctly that you blocked off the hose between the stepper and each of the throttle bodies? You didn’t block off the hose between the stepper and air Box?
Great result,

Hi,

yes I blocked hose intake port on each of throttle bodies.

Hi,

I removed the idle valve  from the bike and did some tests. First of all I disassembled the valve - removed stepper motor. The valve itself is perfectly clean. than I checked function of stepper motor . When I  switch ignition ON and OFF again motor start moving to find its home position (fully closed), then it go back little bit to keep valve little open. I tried to block the pinion by finger and find that I have to use quite strong force to stop it. From my point of view the stepper motor is OK. That I want to check if the fully closed valve is airtight. So I switched ignition ON and OFF again and disconected the stepper connector in the moment when stepper went to home position. Then I applied pressure air 2bar to intake of valve and checked outlet of valve for air flow. There was no air flow . So the result is that valve and also its stepper motor is working as it is expected .  Now it seems that the problem is not idle valve but its regulation. I dont´know exactly on what are input variables .I would say that RPM, engine temperature, air temperature and TPS position. All of them are OK. Now I really don't know what might be the root cause .

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Today I have changed complete idle stepper motor and valve which I borrrowed from my friend bike and the result is still the same. So it is really not a stepper motor issue! I looked at params in Guzzi Diag and was surprised how short is injection period. I remember that at idle RPMs there was about 2ms injection period on good running bike but now there is only 1,3ms at 5°C and 0,7 - 0,9ms at 80°C! I really have no idea what could be the problem, maybe ECU. Can anybody help?

GuzziSteve wrote:

Did you check the O2 sensor parameters, is it working correctly?

I don't remember how its named in guzzidiag, "O2", "oxygen" or "Lambda"... Its the sensor that measures mV, its supposed to fluctate between 100 and 900 mV - after its heated up.
I dont remember witch value is the "too rich", the low or the high mV.
Maybe your sensor is stuck to the "too rich" value?