• Ciao Guest - You’ve landed at the ultimate Guzzi site. NEW FORUM REGISTRATIONS REQUIRE EMAIL ACTIVATION - CHECK YOUR SPAM FOLDER - Use the CONTACT above if you need help. New to the forum? For all new members, we require ONE post in the Introductions section at the bottom, in order to post in most of the other sections. ALWAYS TRY A SEARCH BEFORE STARTING A NEW TOPIC - Most questions you may have, have likely been already answered. DON'T BE A DRIVE-BY POSTER: As a common courtesy, check back in and reply within 24 hours, or your post will be deleted. Note there's decades of heavily experienced Guzzi professionals on this site, all whom happily give endless amounts of their VALUABLE time for free; BE COURTEOUS AND RESPECTFUL!
  • There is ZERO tolerance on personal attacks and ANY HYPERLINKS to PRODUCT(S) or other competing website(s), including personal pages, social media or other Forums. This ALSO INCLUDES ECU DIAGnostic software, questions and mapping. We work very hard to offer commercially supported products and to keep info relevant here. First offense is a note, second is a warning, third time will get you banned from the site. We don't have the time to chase repeat (and ignorant) offenders. This is NOT a social media platform; It's an ad-free, privately funded website, in small help with user donations. Be sure to see the GTM STORE link above; ALL product purchases help support the site, or you can upgrade your Forum profile or DONATE via the link above.
  • Be sure to see the GTM STORE link also above for our 700+ product inventory, including OEM parts and many of our 100% Made-in-SoCal-USA GTM products and engine kits. In SoCal? Click the SERVICE tab above for the best in service, tires, tuning and installation of our products or custom work, and don't miss our GT MotoCycles® (not) art on the BUILDS tab above. WE'RE HERE ONLINE ONLY - NO PHONE CALLS MADE OR RECEIVED - DO NOT EMAIL AND ASK QUESTIONS OR ASK TO CALL YOU.
  • Like the new V100, GuzziTech is full throttle into the future! We're now running on an all-new server and we've updated our Forum software. The visual differences are obvious, but hopefully you'll notice the super-fast speed. If you notice any glitches or have any issues, please post on the Site Support section at the bottom. If you haven't yet, please upgrade your account which is covered in the Site Support section or via the DONATE tab above, which gives you full site access including the DOWNLOADS section. We really appreciate every $ and your support to keep this site ad-free. Create an account, sign in, upgrade your account, and enjoy. See you on the road in 2024.

intermittent engine cutout on 01 California - 5/11 update

mwest

Tuned and Synch'ed
Joined
Nov 1, 2008
Messages
76
Location
Hollister, CA
See last post for 5/11 update.

A little background. Sunday before last, I did a 6 hour ride on my 01 Cal Special (with 50k miles) all on backroads ranging from first gear twisties to 100MPH straights. Bike ran flawlessly all day. Being spring, there are lots of bugs out on the central coast so the bike was really ugly when I got back.

This last Saturday, I washed and detailed the bike but didn't ride it till yesterday. On the way into work in the morning (57 mile commute) the bike surged a couple of times while cruising on the fwy about 70MPH in 4th gear. It was like the engine cutout for a fraction of a second and then came back on.

After work, I rode to Alviso for the Bay area monthly Guzzi Dinner, which is 3-4 miles from work. On the way over it surged a couple more times on the freeway at a constant speed in the same RPM range as it did in the morning.

After dinner, I had the long ride home in the dark and the problem became more frequent. probably did it 15-20 times while riding home. Always felt the same as though the engine was cutting out very briefly. Always when holding a constant RPM around 4k +/- 200 and never while accelerating or decelerating. Didn't seem to be related to vibration or hitting bumps either. When it happens, there is no interruption to lights, gauges, or any other function that I could see.

Naturally, I'm scheduled to go to the Visalia Not-a-rally next week and not comfortable riding around in the middle of nowhere with this kind of intermittent issue and hoping to sort it out quickly.

My sidestand switch was disconnected years ago. I've never had a problem with my electronic petcock and tend not to think that would be an issue as it doesn't seem to be related to vibration.

As I said earlier, the bike ran great prior to getting washed so perhaps I got something wet or knocked something loose while cleaning. Or perhaps it doesn't have anything to do with that. Maybe a sensor going south, perhaps?

One other tidbit to note is that a year or so ago, I noticed my tach kind of drags when it gets around 4500. If you're accelerating and watching the needle, it climbs gradually and it gets around that area, it slows down for a few seconds and then seems to recover. Don't know if that could have anything to do with current issue as it's been that way for a long time, but thought I should mention it.

Any ideas of what to check and how to check it would be appreciated. If there is a part I might need for testing, I'd need to get it ordered asap in order to get it here in time.
 
Re: intermittent engine cutout on 01 California.

Washing the bike might be a clue. Check that the drain tube under the gas cap is not blocked. If it is, any water that makes its way under the cap will eventually make its way into the tank itself. Water in the gas can induce the symptoms you are describing.
 
Re: intermittent engine cutout on 01 California.

Mark, as Dave states above, the water is certainly a definite culprit. Could be water in the fuel, could be water sitting in the connections to the fuel pump... or worse it could be the beginnings of fuel pump failure or clogging fuel filter. When have you changed the filter last? Other then that, now that some time has passed, has the problem fixed itself?
 
Re: intermittent engine cutout on 01 California.

Fuel filter replaced about 3000 miles ago with stock UFI. Fuel pump is original.

I did fill up with gas after work and prior to the ride home from bike night. Didn't notice any water around the filler when the cap was off but I suppose that could have dried up if there was some.

If there is water in the gas, will it eventually get worked out or do I need to drain the tank and refill?
 
Re: intermittent engine cutout on 01 California.

There are a few market additives you can get that claim they can "remove" water from the tank, i.e.; http://www.goldeagle.com/brands/heet/

Is it still doing it then?

Also, electrical issues (such as a not fully seated coil wire) can cause similar problems too, just not water related, but if you had the tank off recently, worthy of a check.
 
Re: intermittent engine cutout on 01 California.

bike nite was yesterday and it acted up on the way home. Didn't ride it to work today.

Tank hasn't been off since the fuel filter was replaced. Don't think I could have disrupted a coil wire but will have a look.

Would any of the engine sensors cause this kind of problem?
 
Re: intermittent engine cutout on 01 California.

I can think of a few things , TPS might be wet. the coil packs are visible so i would check there
both the High tension lead and the signal connector.
I have never had this happen to me so i am at a loss
good luck keep us informed
 
Re: intermittent engine cutout on 01 California.

I would eliminate the most likely culprit and get some water eliminator into the tank right away and take the bike for a spin.

If that's not it, then look and the spark plug cap and coil lead next like Todd said.

The next thing on the list is the kill switch. I have found defective switches (older models) by pressing on the switch (run) when it cuts out, if it responds immediately and consistently that's probably your problem.

Guzzis have souls, so it's possible she might just want to become a garage queen and doesn't want to be ridden anymore except in parades of course. I suggest getting a Quota to ride the back roads and for commuting.
;) :laugh: :laugh:
 
Re: intermittent engine cutout on 01 California.

mwest said:
Would any of the engine sensors cause this kind of problem?
Possibly, but usually it means that the bike simply would not start at all, not symptoms like you are describing. Silly question, did you check all of the fuses? Is the bike over or under charging by chance? Don't trust the idiot light on the dash.
 
Re: intermittent engine cutout on 01 California.

Since I use heated gear in the winter, I have a voltmeter. It's reading about where it always does without the heated gear on.

Had not looked at any fuses but seems to me a flaky fuse would be something that would act up based on vibration or jarring.

Wonder if I can find some of that water eliminator at an auto parts store. Would seafoam work for that as well?
 
Re: intermittent engine cutout on 01 California.

Had same symptoms on a Ducati after every dealer service, battery terminal loose.
Sometimes the "hick-up" (like toggling the kill switch on-off-on) would coincide with erratic turn signal operation if I just happened to be turning at the right time.

Another Ducati rider had same problem, but it was a loose terminal connection INSIDE the battery.
 
Re: intermittent engine cutout on 01 California.

Found some of the HEET water eliminator and added it to the tank. Said to add the whole bottle but that it was good for 20 gallons. I added about a quarter of it to about 4 gallons.

Also pulled all fuses and relays. Fuses checked good with a meter as well as visually. Some relay contacts were a bit oxidized but nothing worse than typically seen on a car or bike.

Sprayed de-oxit on all contacts and re-seated everything. Checked coil connections and they all looked fine. No sign of corrosion or water penetration. Battery connections tight and clean.

Generally looked around at all the wiring that I may have come in contact with when cleaning and didn't see anything amiss.

Started bike on centerstand and ran it a bit in the range where the hiccups occurred and all ok. A minute on the stand doesn't mean much so I'll likely ride it on the weekend and see how it does.

Thanks for all the tips and suggestions.
 
Re: intermittent engine cutout on 01 California.

Couldn't ride on the weekend so rode in to work this morning. There was one slight surge a couple of blocks from my house and then it ran fine for the next 30 miles. Then all of a sudden it started surging pretty consistently for the next 10 minutes or so and then a little later, the frequency became less but it didn't go away. While it was surging, I kept my eye on the voltmeter during this time and saw no changes to battery voltage.

While on the freeway I was trying to keep it running at constant RPM's in the same range as last week up until the surging started. Then I started to experiment raising/lowering the engine speed.

I found that there was no surging at all over about 4800 RPM in 4th gear. Also nothing under about 3800.

Another thing I noticed is that in 3rd gear, the surging seemed to occur more frequently at a slightly higher RPM than in 4th; maybe 200 higher. I'm thinking that the same TPS position would give you a higher RPM in 3rd than 4th and perhaps it's got a bad spot on the pot.

Another thing I failed to mention earlier is that I have a PCIII. I plan on disconnecting that for the ride home and see if anything changes. I don't have any reason to suspect that but may as well rule it out.

May also go pick up a Harley TPS to swap and see if that fixes it.

Any other suggestions?
 
Re: intermittent engine cutout on 01 California - 4/8 update

Hi Mark,

Can't remember - do you have a VDSTS to recalibrate the TPS? If you have one hook it up and see what your TPS reading is as you operate the throttle.
 
Re: intermittent engine cutout on 01 California - 4/8 update

No VDSTS. Have always used a DVM for setting the TPS.
 
Re: intermittent engine cutout on 01 California.

mwest said:
Another thing I failed to mention earlier is that I have a PCIII. I plan on disconnecting that for the ride home and see if anything changes. I don't have any reason to suspect that but may as well rule it out. May also go pick up a Harley TPS to swap and see if that fixes it.
Did you say you pulled and cleaned the TPS already? I would certainly start there if you've limited it to a specific throttle position. Are you seeing any dead spots with the DVM? Certainly replacing the TPS might do it either way.
For the PCIII; If it starts, it's working, and that shouldn't be the cause of it unless something mechanical is going very wrong, and the fuel map requirements have drastically changed. Or the bike has ridden itself out of tune, which is a far stretch, but might be the case... thought without AFR data, it's only a guess.
 
Re: intermittent engine cutout on 01 California - 4/8 update

How do you clean the TPS? Isn't it a sealed Pot?

At lunch, I'll stick my meter on the TPS and see if I see anything strange through the range. May be hard to see in a static condition though.

Don't really see a logical explanation for suspecting the PC3 other than maybe the outputs for the injectors could be intermittent or something like that. Haven't changed anything on the bike that would affect air/fuel in a long time other than replacing the air filter when the fuel filter was changed.
 
Re: intermittent engine cutout on 01 California - 4/8 update

mwest said:
How do you clean the TPS? Isn't it a sealed Pot?
At lunch, I'll stick my meter on the TPS and see if I see anything strange through the range. May be hard to see in a static condition though.
Don't really see a logical explanation for suspecting the PC3 other than maybe the outputs for the injectors could be intermittent or something like that. Haven't changed anything on the bike that would affect air/fuel in a long time other than replacing the air filter when the fuel filter was changed.
You simply remove the TPS from the bottom of the throttle body, and clean the contact points. Re-assemble and ride. The TPS itself cannot be disassembled.
You will see erratic readings (or not) from a TPS DVM probe. If any fluctuation outside of a steady increase in mV it's either dirty or bad.
The PCIII doesn't sound like it's your issue here... usually never is, but typically the first thing people think. I have well over 200k miles on PCIII USB's with one issue ever, a corroded pin within the ECU connector after 9+ hard mile years. Symptom, it just didn't start.
 
Re: intermittent engine cutout on 01 California - 4/8 update

I mark the body of the TPS and the throttle body. Sharpie or a kinfe
pull the TPS and use brake cleaner on the contacts and shoot some on the shaft turning it a few times with my finger or a screw driver. you will see what I mean after you remove it.
I have done this on two different bikes I have seen an improvement.
the other thing is lately I don’t even use a Volt Meter
I reinstall on a cold motor try to start it with the fast idle lever set slowly adjust the TPS till it starts on its own.
Then after warm I back the TPS off till the motor stumbles then ease it back a little. snug it blip the throttle till I get a nice grisp rev.
This is my 4th cali FI type bike. On the first one I did it using the DVM never got that bike to be smooth.
 
Re: intermittent engine cutout on 01 California - 4/8 update

Put a DVM on the TPS in the parking lot. Saw no odd behavior on the voltage from 525mv at idle to 4.75V wide open.

Reading went steadily up and down with throttle position. When I get home, I'll pull it off and spray it with de-oxit just for the hell of it.

Some people had also mentioned the relays. I still have all the original relays and never had an issue but if there is one in particular that might cause this problem, I may swap it with another. Any thoughts on which one might cause the symptoms I'm seeing?

Thanks to all for the assistance.
 
Back
Top