98 EV Tuneup setting TPS question

[bigbikerrick]

Hello Folks, I have been sorting my 98 EV, and getting the fuel injection fine tuned. The bike is actually running very well, but It does not run right setting the TPS to 378 mv at idle as recommended for bikes with the P-8  ECU. I have to set the tps voltage to around 450+ MV to get it to accelerate smoothly, and not buck and backfire. I have adjusted the valves, synched the TBs, and experimented with the air screws from 1/2 to 1.5 turns out. I have turned the idle mixture screw on the ecu 1/2 turn to richen the idle with the TPS set at the lower 378  MV setting, and it still will buck, and backfire.  The bike will only run decent with the TPS turned where the idle voltage is from 450mv to 500mv.
FWIW, I have replaced the sensor on the flywheel right side, spark plugs, and ignition wires/caps.The bike has a new K&N air filter, and an aftermarket exhaust  H pipe. The bike idles nice, no problems there.  The spark plugs look like its  running just a tad rich
Any ideas or suggestions?
Thanks
Rick Duarte

[Tom H]

If it was me, I'd go with .450V and see if it's running too rich. I think you would be fine.

Question. Did you set the TPS to .150V with the TPS TB idle screw backed out and the tie rod between the TB's off? Then set the .450V?

Your probably fine, but could make a difference.

Tom

[pehayes]

Is it the original TPS?  22 years old.  It could be the TPS contacts dirty or worn at that critical point.
Have you tried to drill and clean the TPS?  The sensor sits BELOW the throttle body.  When  you turn off, any residual fuel in the inlet stream can drain down the butterfly stem into the TPS to evaporate and leave gum residue behind.
Have you borrowed a TPS from someone else to test another unit for comparison? 

There is a replacement a lot cheaper than Guzzi.  Try this:
https://ca-cycleworks.com/pf3c.html

How are you testing for TPS voltage?  Variety of ways to poke pins into the wires.  But there is a far better way.  Aftermarket cable that plugs in directly and gives you exposed wire ends for clamping test wires.  See here:
https://www.summitracing.com/parts/cei-109172?seid=srese1&gclid=Cj0KCQjw0PWRBhDKARIsAPKHFGhZ7HO9v4x8cO__9lSDK-qnU90Vk57GS8zSa3dF-35D71ylcPaGrNcaAmNxEALw_wcB






Check out this video:
https://www.youtube.com/watch?v=cZK9fVvNaC4

Patrick Hayes
Fremont CA

[bigbikerrick]

Thank guys for the prompt replies. When I first started to tun the bike, I started by backing off the idle screws and setting the base to 150 mv. The previous owner replaced the TPS 2 years ago, and although  it looks almost new, who knows maybe it has a bad spot. I made my own harness, That I leave in place, with connectors to hook up my multimeter, for TPS checking.

I have not drilled/ cleaned the TPS, I should probably get a spare, before I try drilling this one, in case I damage it.

Rick.

[bigbikerrick]

Patrick, Very interesting video. So those were all brand new TPS s that had glitches!  Cool testing machine, they built. Those guys are some serious "Geeks"!

Does that mean that CA cycleworks tests all their TPS s, on their trick little gadget, before selling them?

You just convinced me to buy a spare TPS to try out.
Rick.

[lucky phil]

Hello Folks, I have been sorting my 98 EV, and getting the fuel injection fine tuned. The bike is actually running very well, but It does not run right setting the TPS to 378 mv at idle as recommended for bikes with the P-8  ECU. I have to set the tps voltage to around 450+ MV to get it to accelerate smoothly, and not buck and backfire. I have adjusted the valves, synched the TBs, and experimented with the air screws from 1/2 to 1.5 turns out. I have turned the idle mixture screw on the ecu 1/2 turn to richen the idle with the TPS set at the lower 378  MV setting, and it still will buck, and backfire.  The bike will only run decent with the TPS turned where the idle voltage is from 450mv to 500mv.
FWIW, I have replaced the sensor on the flywheel right side, spark plugs, and ignition wires/caps.The bike has a new K&N air filter, and an aftermarket exhaust  H pipe. The bike idles nice, no problems there.  The spark plugs look like its  running just a tad rich
Any ideas or suggestions?
Thanks
Rick Duarte

The idle TPS setting is designed to simply be a starting point after setting the closed throttle TPS base setting so when you start the engine for balancing and airscrew adjustments the idle is "in the ballpark" nothing more. It's not a hard and fast setting.

Ciao

[JoeB]

Just an observation but the recommended 378 mv setting on the tps was for a stock bike.
Your K&N air filter and H pipe change the dynamics a bit.
The bike was factory set for best emissions rather than rideability.
Guzziology, at least my 90's edition recommended settings outside factory specs if needed.
Just curious but what is the idle rpms with the tps set at 450+?

[antmanbee]

The idle TPS setting is designed to simply be a starting point after setting the closed throttle TPS base setting so when you start the engine for balancing and airscrew adjustments the idle is "in the ballpark" nothing more. It's not a hard and fast setting.

Ciao

+1

If you did not take the rubber boots off and clean the throttle bores and butterfly valve thoroughly when you did the base TPS setting you could be off quite a bit.
It is most important to get this setting as accurate as possible because this is the reference setting that the ECU will base all it's calculations on for throttle opening.
As Phil said, the set screw setting is just to get the idle RPMs in the proper range and will not affect overall running except for idle speed.

[bigbikerrick]

Thanks guys, for the very knowledgable responses. I have not cleaned the butterfies and throttle bores, I need to take those apart and clean them. Thanks for the tip!

I suspected that the TPS setting recommended is for a stock bike and best emissions readings, where in my case with the K&N and H pipe would require more fuel. Makes total sense.

As far as the question of what is my idle at, I dont exactly know, as my tach is inoperative,and I am waiting for a new speedhut tach to arrive. I dont have any other way to check RPMs accurately, but by "ear" it seems like its idling around 1000-1200 rpms.
Thanks again,you guys Rock!!   
Rick.

[John A]

When fine tuning the tps I found it beneficial to do it at the top, or wide open throttle. At wot take a measurement. It should be at least 80% of the 5v reference voltage . You can adjust it in increments of .01 volts by checking it at wot which is repeatable because you can hold it against a hard stop. If you do it at the bottom where you close the throttle it depends on how hard you close it and it’s not repeatable with that variation . .01 volts make a noticeable difference in how it runs on a finely tuned engine

[pehayes]

Does that mean that CA cycleworks tests all their TPS s, on their trick little gadget, before selling them?

That is my understanding.  My new TPS came with its own little printout shown in the video.

Patrick Hayes
Fremont CA

[bigbikerrick]

Thats an interesting way of doing the set up, John, A. If I remember correctly, at WOT, mine was reading around 4.88 volts.

Thats really cool, Patrick, that they test all the TPSs that way we are assured we got a good one. Well worth the money, IMHO, rather than throwing in a Harley TPS which isnt exactly right.
thanks
Rick

[lucky phil]

When fine tuning the tps I found it beneficial to do it at the top, or wide open throttle. At wot take a measurement. It should be at least 80% of the 5v reference voltage . You can adjust it in increments of .01 volts by checking it at wot which is repeatable because you can hold it against a hard stop. If you do it at the bottom where you close the throttle it depends on how hard you close it and it’s not repeatable with that variation . .01 volts make a noticeable difference in how it runs on a finely tuned engine

I tell you what I do. I clean the throttle plates and remove the air screws and clean them and their seats. I disconnect the throttle linkage and unscrew the idle screw/s until the throttle plate is seated in the TB bore. I then lightly tie wrap the throttle plate in this seated position and adjust the the TPS to the required MV. I then with the opposite throttle plate bottomed adjust the connection linkage so there it connects perfectly with zero interference and then remove the tie wrap and adjust the idle screw to achieve in my case 450mv rough idle position. I then go onto the balancing and final idle adjustments. This way there is no movement of the throttle plate off the fully closed position and setting the TPS is a bit easier.

Ciao 

Ciao   

[bigbikerrick]

Good useful information, Lucky Phil. Last night , I took the EV for a short test ride after installing a new rear tire, and I could smell gasoline. Actually, I have been smelling gas, on and off  for a while now, while riding the bike.
 I started investigating the source, and the area of the right throttle body, where the rubber sleeve connects to the round tube going to the air box. There was some fuel, under the sleeve, the clamp bolts were not real tight, so i removed the rubber sleeve, there was a bit gas inside that came out, when I disconnected the sleeve.
  Is this normal? It seems the area between the throttle body and air box should be dry of  gas? Its behind the injector.... also on the ev , the pipes connecting to the airbox seem to tilt slightly downwards, towards the air box, so it does not seem right for gas to be there.
  Anyway, I sprayed carb cleaner into the TB/ butterfly area , and flushed quite a bit of crap out. I think as was suggested, a TB cleaning is in order.
  Do you guys have any other ideas, or suggestions?
thanks alot
Rick.

[lucky phil]

Good useful information, Lucky Phil. Last night , I took the EV for a short test ride after installing a new rear tire, and I could smell gasoline. Actually, I have been smelling gas, on and off  for a while now, while riding the bike.
 I started investigating the source, and the area of the right throttle body, where the rubber sleeve connects to the round tube going to the air box. There was some fuel, under the sleeve, the clamp bolts were not real tight, so i removed the rubber sleeve, there was a bit gas inside that came out, when I disconnected the sleeve.
  Is this normal? It seems the area between the throttle body and air box should be dry of  gas? Its behind the injector.... also on the ev , the pipes connecting to the airbox seem to tilt slightly downwards, towards the air box, so it does not seem right for gas to be there.
  Anyway, I sprayed carb cleaner into the TB/ butterfly area , and flushed quite a bit of crap out. I think as was suggested, a TB cleaning is in order.
  Do you guys have any other ideas, or suggestions?
thanks alot
Rick.
/quote]

Guzzi's pool fuel in the intakes during the warm up process until the engine is fully up to temp due to cold inlet tract and a rich warmup mixture. If you happen to shut the engine down before the engine is fully warm and the rich trim is still in effect you may see fuel dripping from the throttle body shaft. This is due to the fuel pooling and the vertical throttle shafts and worn seals. Normally after hot running there should be no fuel in the intakes. Ducatis dont have this issue although they use pretty much the same t/bs on a lot of their models from the same era because their t/b shafts are horizontal.
You're other issue may well be dirty injectors that are not providing a good spray pattern and also leaking when the engine is shutdown. I would have the injectors cleaned myself. It's cheap to have done professionally at around $30 per injector.
The other thing to check is the engine temp sensor is ok. Put a meter across the sensor pins and make sure it's not open circuit.   

Ciao

[bigbikerrick]

Here is the update, guys. Today I removed the whole intake assembly, and cleaned the tbs. they were pretty dirty.I then reset everything from step one, setting the tps voltage, and synching the TB's . I was able to get it to run good with the idle voltage around 378mv , and the plugs look good. I am still getting a little "popping" in the pipes on deceleration, but I may be able to eliminate that by tweaking the idle mixture screw.
thanks alot,
Rick.

[lucky phil]

Here is the update, guys. Today I removed the whole intake assembly, and cleaned the tbs. they were pretty dirty.I then reset everything from step one, setting the tps voltage, and synching the TB's . I was able to get it to run good with the idle voltage around 378mv , and the plugs look good. I am still getting a little "popping" in the pipes on deceleration, but I may be able to eliminate that by tweaking the idle mixture screw.
thanks alot,
Rick.

A sign of possible dirty injectors. Another member just recently solved this popping issue on the overrun after I suggested an injector clean.

Ciao

[bigbikerrick]

Thanks Phil, I am going to try running a bit of techron through it, and see  if it helps.Otherwise a professional cleaning may be in order.
Rick

[John Croucher]

Is the TPS good?  I have seen them with bad spots that are worn.  Causing bad voltage signals.  Worn and bent contacts.  They will come apart for inspection.

Check with a multi meter also for consistent voltage changes as it is rotated.

[lucky phil]

Is the TPS good?  I have seen them with bad spots that are worn.  Causing bad voltage signals.  Worn and bent contacts.  They will come apart for inspection.

Check with a multi meter also for consistent voltage changes as it is rotated.

The early PF09 TPS's are cleanable but the later PF03 linier and non linier aren't to my knowledge. You won't get a consistent voltage output from a non linier PF03 TPS. At one point around 40% the voltage output to rotational degrees changes.  I did a piece on PF09 dismantling and cleaning a while back on the V11 forum.

https://www.v11lemans.com/forums/index.php?/topic/20664-v11-daytona-project/page/20/#comment-247765

Ciao

[bigbikerrick]

To me the TPS seems like its OK.John, I have not been able to find any "dead spots" using the throttle and multimeter, while slowly opening the throttle. I have a new one coming in from CA cycleworks, so I can rule that out.  I almost hate to mess with it, because its running pretty darn good right now after the cleaning, and re tune, but I want to get it perfect!
thanks
Rick

[bigbikerrick]

Thanks for that link, Phil, I will check it out.
Rick

[bigbikerrick]

Holy Cow, Phil, you have a V 11 sport "greenie" with a Centauro motor! You da' man!
Rick.

[lucky phil]

Holy Cow, Phil, you have a V 11 sport "greenie" with a Centauro motor! You da' man!
Rick.

Thank you, it was a dream I had for ten years to create this bike. It's not the first one in the world but I'd put the quality of construction against any other one around. It's still a build in progress with later 43mm forks from the KT bikes and light weight PVM wheels in the process of being fitted. Someone will get a nice bike one day when I'm gone. It will be my legacy. Hopefully someone will appreciate what they get. 

Ciao

[bmc5733946]

Some diesel injector repair shops are equipped to clean Bosch injectors. Pop them out and run them by a shop and see. This works around here, sadly many people just replace them. The injector shops can usually tell you if they need replacing.

Brian

[lucky phil]

Some diesel injector repair shops are equipped to clean Bosch injectors. Pop them out and run them by a shop and see. This works around here, sadly many people just replace them. The injector shops can usually tell you if they need replacing.

Brian

Petrol Injector cleaning services are common these days as virtually every car uses injectors. You can even buy your own rig for 6 or 700 bucks and combined with a $35 1 litre ultrasonic cleaner get it done. Some cheap rigs have a built in Ultrasonic cleaner.

Ciao

[weevee]

My own bike, with a Daytona motor and open exhaust + foam-filters, needs 450mv to idle correctly too.  This is with a reset throttle linkage and a new TPS.  I believe it's running a bit rich (..soot in the end-cans, although not sooted plugs), but if weakened any further it's not happy. 

[bigbikerrick]

Phil, I would love to see some pics when its finished!
Rick

[lucky phil]

My own bike, with a Daytona motor and open exhaust + foam-filters, needs 450mv to idle correctly too.  This is with a reset throttle linkage and a new TPS.  I believe it's running a bit rich (..soot in the end-cans, although not sooted plugs), but if weakened any further it's not happy.

You can't avoid this on a road bike.

Ciao

[lucky phil]

Phil, I would love to see some pics when its finished!
Rick

Do you mean this Rick? Still waiting on the wheels and the later forks are almost ready to fit.

Ciao