Hick ups and back fire

[Delman]

Hi all

back again with another Guzzie problem on my 2002 v11 Lemans

any help would be greatly appreciated

 

problem description:

 

a little difficult to start, but not too bad say four tries

as the engine is turning to start you can hear air escaping from the left cylinder almost like the timing is off or the valves aren't closed 

after she is running every thing is alright slightly rough but not too bad

when the throttle is blipped a little hesitation is noticed almost like a hick up

after short while say 2 to 3 miles of riding and under 3000 rpm every time the throttle is applied there is a hick up and hesitation and the she catches on as she gets warmer say 5 miles there is an occasional back fire all from the left cylinder

 

work I have done to the bike:

 

new battery

fuel vapor canister was removed by me and ports at the intake caped

new plugs wire and plug caps cleaned

head temp sensor on the right cylinder removed and tested all good 

 

this might be coincidental but in the last two weeks its getting warmer around here thats when my problems started

 

planning to take advantage of the up coming long week end and remove the tank adjust the valves and clean all electrical connections and do some maintenance (air and fuel filters)

 

like I said earlier any help would be greatly appriciated

this forum has helped me tremendously with my previous issues

this is my first Guzzie and I have owned it for half of the year and love it

I guess you could say we are still bonding 

[docc]

I hope you don't mind, but we're all gonna be bonding with your Guzzi now!

 

" . . . you can hear air . . ." makes me think you should look for intake or exhaust leaks on the left. It's not uncommon for the rubber intake to slip off and give trouble like you describe. Otherwise, it could simply be time for a full tune-up from valves and TPS and spark plugs through throttle body balance,

[JBBenson]

....what Docc said.

 

When I was tuning mine I did notice that backfiring often blew the rubber boots partially or totally off. Partially off was hard to notice until I looked closely. 

 

I would check the rubber boots first, followed by making sure the exhaust is nice and tight all around, then check the disconnected TPS setting. It does run so maybe the valve clearance is OK. Finally dump in some Redline Si-1 fuel system cleaner. Can't hurt.

 

Are you running the stock ECU map? The US stock map made my bike stumble around 3.5K until I had it remapped. 

 

Tiny things make the V11 run like shit. Mine drove me crazy for a year. Once it is sorted you will love it even more. 

[fotoguzzi]

if not the rubber boot to the throttle body being loose I'd to a TB sync, assuming the valves in spec.

[Kiwi_Roy]

If none of the previous works perhaps do a compression test, hold the throttle open.
A dirty ignition switch can cause popping and farting, flick the switch a few times to see if it improves.


Sent from my shoe phone

Corrected by PC

[Delman]

once again the support on this site amazes me

thank you all for chiming in to help

 

i failed to mention that i  am the second owner of the bike, the original owner rode it for 17000 miles and as far as i can tell did not do anything to the bike it still had the original battery and tires on it, they looked more like slicks than tires.

 

Docc, i got new plugs in there, plug wires i trimmed the ends and re installed them they were running fine before but i should replace them with new, the intake boots show their age but i sprayed a little starting fluid on them while the bike was idling to see if i get a surge in the rpm and it did not. i will check exhaust and the boots again. I am doing the valves this weekend, TPS?(is that throttle positioning system?) and TB can some one point me in the direction of where i can find how to direction on the forum please.

 

JB, as far as I know ECU and the map should be factory stock, plus i am not smart enough to mess with that stuff, previous owner was in the same boat as me.

 

i ll be working on her this weekend, valve adjustment, new fuel filter, check exhaust and intake for leaks, new plug wires plug boots

if some one could point me to a how to on valve adjustment and TB balancing and TPS feel free to  point them out to me.

once again thank you for your advice

 

Delman

[Kiwi_Roy]

There's a tutorial 2nd topic down in the FAQ section, it seems a bit confusing if you haven't done one before.

the TPS is set to 150 mV with the throttle body fully closed (idle stop and fast idle cam not touching) Once you have set the 150 mV you never move it again.

In a later step you read the Voltage while adjusting the idle stop opening the throttle to see 521 mV, this is just the initial idle position, later you will change this to get the idle speed where you want it.

 

Don't be surprised if it takes several attempts

 

The cheapest and IMHO the best balance tool is a manometer made of 10 ft of plastic tube, a 3 ft stick and some engine oil

make a U at about the 6 ft point (one end is longer to reach over the bike) and fasten it to the stick.

Dip one end into a bottle of oil and suck on the other to get about 18" of oil on either side of the U, there you have it.

To connect to the throttle bodies if you don't already have an adapter these can be made from a pair of 6mm grease nipples. file the tips off the threaded end to release the ball and spring, throw those away.

As the engine warms up the plastic hose will fall off so fasten it with a twist tie or similar.

 

BTW, you can tap into the TPS mV near the ECU connector either by poking a pin through the wire going to pin 11 (Black/ Violet I think) IMHO it doesn't hurt to make a permanent test point there, a short wire ending in a blue crimp link works well as a meter jack, the other connection can be battery Negative or even chassis.

If you look at your Guzzi manual the TPS may be shown incorrectly (both mine show it wrong), Luigi loves to keep us guessing.

[JRD]

Delman- I purchased an '02 LeMans in January which had super low mileage,(3,000)and at first, it ran great. However, it started acting up very similar to your symptoms, hiccups, rough idle and almost stalling at traffic lights. After adjusting the valves, (.006 Intake/.008 exhaust), I followed the tutorial, cleaned and adjusted the TPS and balanced the throttle bodies. While I was at it I removed the air filter boots so I could look inside the throttle bodies. I couldn't believe the amount of crud/carbon build up inside there for such a low mileage bike! Took the air fuel screws out and used two cans of carb cleaner to flush everything out. It looked like small pieces of varnish were coming out. I also replaced the fuel filter, figured if my throttle bodies were clogged up, there was a good chance the filter had collected crud also, and my filter had a small leak. Put everything back together and now it runs great. Use patience, follow the tutorial and approach it systematically one step at a time, you'll get it running correctly. Scud recently post a step by step tune-up procedure on "Sorting a Multiple Owner LM". And don't hesitate to ask for help here, The members have been fantastic.

 

Jerry

[Midle Age Warrior]

Delman I was in your shoes a few months back, a complete newbie. By now I know my bike more than all my fellows riders together and my bike is pourring like a kitty and all of this thanks to the forum help.

At first could sound dificult and take time but soon you will be doing your TPS and TB balance like a pro, I did what Kiwi Roy said abiut clean the starter switch then just follow the instructions and you will be there faster than you can say Guzzibiri .

Good luck

[Scud]

While I was at it I removed the air filter boots so I could look inside the throttle bodies. I couldn't believe the amount of crud/carbon build up inside there for such a low mileage bike!

 

Use patience, follow the tutorial and approach it systematically one step at a time, you'll get it running correctly. Scud recently post a step by step tune-up procedure on "Sorting a Multiple Owner LM". And don't hesitate to ask for help here, The members have been fantastic.

 

Jerry

 

My throttle bodies were a mess too. I wrote that procedure because it was my first time tuning this bike; I failed twice, and I had some conflicting sets of instructions. I had some extra challenges, because I am undoing a lot of modifications - and I'm not sure if the Kit Racing ECU programming was modified.

 

Here's a link in case it's helpful:  http://www.v11lemans.com/forums/index.php?showtopic=18967&page=5 You will need to endure a tractor joke on the way to useful stuff at post #66.

 

Delman - it sounds like yours was recently running well and I assume you have not changed any equipment. So the process should work well for you.  Be slow and meticulous - maybe you can get it right the first time.  

[Delman]

thanks fellows for all the advice and encoragment

part of my problem is i don't have a good manual or i should say couldn't find a manual

this forum is my manual

even though i am a decent wrench, never had to deal with electronic fuel delivery system 

there is always first time for every thing

i ll keep you guys posted on the progress 

[Delman]

I gotta hand it to you guys

You guys know your stuff

after reading the posts when I got home from work went and looked at the boots again and guess what

the boot on the side in question has slipped off the TB.

i am still going to go ahead with a full service as planned

but if you excuse me i got a boot to put on

will keep you posted

life is good again

thanks

[docc]

. . .

this forum is my manual . . .

 

 

 

Heh - right?   not to mention:

[JRD]

Delman- Another inexpensive "modification" I would recommend is insulating the fuel lines. When I removed my fuel tank I discovered my main fuel line was practically resting on the left cylinder head. Pre-heating the fuel in Norway might be a good idea but not so much in sunny, hot and humid Florida. I purchased two packages of fuel line insulation sleeves from a high performance automotive shop. It comes in different diameters, (1/2",3/4" and 1")with a fiberglass weave type fabric on the inside with an aluminum material on the outside. It is very flexible and easily slide on over the fuel line. I used one sleeve over the fuel line from the tank to the fuel pump and the other sleeve from the fuel pump to the filter, and filter to the throttle body. Not sure if it is totally necessary but I thought it would be cheap insurance against vapor lock. I think it was about $18.00 for both sleeves. If you PM me your phone number I will be glad to text you pictures how mine came out.

 

Jerry

[Kiwi_Roy]

Good idea, as long as the fuel is pumping it's ok but stop for a while and vapour lock is a possibility.
It can take quite a while to clear because the pump won't pump it through.

I seem to recall it was a hot topic (pun intended) a couple of years back.