My Guzzi is drinking stupid amounts of petrol

[il_cacciatore]

Alright.

 

Had a look through the forum about Guzzi fuel consumption and found that they are supposed to consume about 35 mpg or somout depending how you ride it.

 

I filled mine upto the max and rode it for 83 motorway miles until the red fuel light came on! Is this normal??? My spark plugs are 'sooty' and when I used the spark plug endoscope type thing that allows you to look into the spark plug chamber bit it was burning with a orange - red flame. Also, when I start her up you can smell petrol, or even when she is just running you smell the whiff of it. All the evidence points to the mixture being seriously rich. The choke doesnt appear to be stuck on as when I turn it on it speeds the tick over up, but it has had raised bars put on it.

 

What causes this? Also, I noticed a bit on the engine that a pipe should be connected to but dont know what or where it should go as its never been on it since I bought it and was thinking that this could be effecting the mixture.

 

How do I rectify the situation? Does it need re-mapped. I know that the last owner re-wired the whole lot including relays and ECU...

 

I've done a forum search but turned up nothing...

 

Also, there seems to be a wire hanging thats not connected to anything, was wondering if this could be effecting petrol consumption being not plugged into anything.

 

Any suggestions are welcomed as I would like to know if A: this is normal and if it isnt how I can go about 'fixing' it.

 

Cheers!!!

[badmotogoozer]

I don't see anything wrong in the first pic but it isn't too clear... The second pic - the hose connection on the fuel regulator is normal, mine never had anything there either. What is likely causing your problem is the second thing you have circled in that pic. If that is where your unconnected wire is I'd bet that is the issue. You've circled the head temp sensor and if a wire isn't connected your ecu thinks the motor is always cold and dumps huge amounts of fuel in. Bad temp sensing was the cause of my horridly low mileage.

 

cheers,

 

Ryan

[il_cacciatore]

Hi, Ryan thanks for the response. The second pick I've circled the bottom of the airbox and a bit that appears to be part of the fuel system. The First pic I've circled a lead that appears to be a plug for something...

[badmotogoozer]

The square blue thing under the second circle, second pic is the temp sensor. Check connections etc. I had to replace the POS plastic housing on mine with a brass one. Once it was sensing proper temp my mileage increased drastically.

[rocker59]

in the second photo:

 

the item you have circled is not supposed to have a hose on it.

 

it's just supposed to be vented to atmosphere.

[ArtD]

Alright.

 

Had a look through the forum about Guzzi fuel consumption and found that they are supposed to consume about 35 mpg or somout depending how you ride it.

 

I filled mine upto the max and rode it for 83 motorway miles until the red fuel light came on! Is this normal??? My spark plugs are 'sooty' and when I used the spark plug endoscope type thing that allows you to look into the spark plug chamber bit it was burning with a orange - red flame. Also, when I start her up you can smell petrol, or even when she is just running you smell the whiff of it. All the evidence points to the mixture being seriously rich. The choke doesnt appear to be stuck on as when I turn it on it speeds the tick over up, but it has had raised bars put on it.

 

What causes this? Also, I noticed a bit on the engine that a pipe should be connected to but dont know what or where it should go as its never been on it since I bought it and was thinking that this could be effecting the mixture.

 

How do I rectify the situation? Does it need re-mapped. I know that the last owner re-wired the whole lot including relays and ECU...

 

I've done a forum search but turned up nothing...

 

Also, there seems to be a wire hanging thats not connected to anything, was wondering if this could be effecting petrol consumption being not plugged into anything.

 

Any suggestions are welcomed as I would like to know if A: this is normal and if it isnt how I can go about 'fixing' it.

 

Cheers!!!

 

My worth- I had very much the same problem with my 04 Italia, fouled plugs, crappy mileage, reeking of fumes cold starting etc. Here is what is probably happening-the oil temperature sending unit is directly responsible for telling the ECU what the temperature is. This unit is mounted in a cheap bakelite housing. it does not transfer heat properly, so the ECU "thinks" that is is cold most all of the time. Fortunately there is a cure, replace it with the earlier one for the (I think) Le Mans that was made of brass. First do this- lFirst look at it, its on the right cylinder, towards the rear, under the tank, and see if the housing is brown or gold/brass colored. If its brown (and I think yours will prove to be ) its bakelite and you need to put the brass one in. First, remove the gas tank, that is extensively covered in here. Then you can get to it easily. Here is a little tip-leave the sending unit screwed in when you unscrew the housing, remove it as a unit. Its much easier to get out that way. It might be a pita anyway You can order the brass one from several places, just call either Moto International or MG cycle and tell whoever answers the phone that you want the brass oil temperature sending unit, they will know what you need. Then, put everything back where you found it I went one extra step, and put some thermal grease in the bottom of the housing, so that the tip of the sender would fully pick up the heat. Put blue locktite on the threads of the housing, and screw it all back in. Put the tank back on and your iback n buisness. My plugs are now coloring a nice shade of pale grey, and the thing runs like a raped ape

[Tom M]

I think the unplugged connector in the first picture might be fuel level sender for the low fuel light. Does your low fuel light work?

[il_cacciatore]

ArtD. i'll need to check to see if it is brass. Seems to be quite a bad flaw then if its the wrong material for the job. My bike is a 2001.

 

Tom M, Yes the low fuel light works fine but it drinks so much fuel that it doesnt matter if it comes on you only got about 5 miles before it runs empty. Was caught out before.

[Dan M]

If the temp sensor is unplugged the infinite resistance throws the computer to full rich. (it thinks the temp is below zero) If the plastic mount is broken but the sensor is still plugged in it will run rich especially with a warm engine but not nearly as bad as having it unplugged.

 

edit: one more thing about that temp sensor - if it is plugged in, unplug it and make sure the pins are not bent over. - Not likely but possible.

[raz]

Tom M, Yes the low fuel light works fine but it drinks so much fuel that it doesnt matter if it comes on you only got about 5 miles before it runs empty. Was caught out before.

Are you saying the unplugged connector in first pic is not the fuel level sender? Then I really wonder what it is. Where is the air temp sensor mounted on a V11?

 

Apart from bad thermal connection that was already mentioned, it's very easy to check if the temp sensors are good or bad themselves. Measure them with an ohm meter, if they are something like 3000 to 4000 ohms in room temperature, they're fine. The exact value is not primarily important, if they go bad they typically go either to shortcut (approaching 0 ohms, more likely a cable problem than the thermistor itself) or complete break (infinite ohms, could be cable or thermistor).

[Dan M]

Are you saying the unplugged connector in first pic is not the fuel level sender? Then I really wonder what it is. Where is the air temp sensor mounted on a V11?

 

Apart from bad thermal connection that was already mentioned, it's very easy to check if the temp sensors are good or bad themselves. Measure them with an ohm meter, if they are something like 3000 to 4000 ohms in room temperature, they're fine. The exact value is not primarily important, if they go bad they typically go either to shortcut (approaching 0 ohms, more likely a cable problem than the thermistor itself) or complete break (infinite ohms, could be cable or thermistor).

 

Good thought Raz, the air temp sensor (in the air box) can be unplugged or open. I don't know how much weight the ecu gives air temp in the equation. Usually coolant temp (oil in our circumstance) has more effect on mixture. Certainly another thing to check though. Like the other, open (infinite) means cold - rich command.

I'm worried about the old owner rewiring everything.

[slug]

One more thing to look at is the TPS. If it's too far out of adjustment it can mess with your fuel consumption. If the bike doesn't have a PCIII on it, the TPS should be putting out .500 volts with the throttle fully closed.

 

What alarms me though, is that you stated the previous owner rewired the ECU??? Um, why and to what extent?

[badmotogoozer]

Ah- I see the the loose connector in the first pic. Yes it definitely connects to something, I remember disconnecting it when I take the tank off. I can't remember what it attaches to though... and my bike is a long way away at the moment.

[il_cacciatore]

I'll need to check these things mentioned.

 

The previous owner from what I can understand had a guzzi dealership do a electrical diagnostic on the bike, don't know the full ins and outs but it ended with him getting the ecu replaced along with the relays and other bits. don't know the full reasons but he had it done due to poor running... maybe i was inaccurate when i said full rewire because maybe that wasn't the case! . I have the actual receipts somewhere... I'll have to endeavour to find out what he had done.

 

I initially thought that this wire could have been a data port to plug in some sort of gizmo?

 

ps i cant remember it being this heavy on fuel when i first got it. badmotoguzzer, you think this connector has something to do with fuel system?

[badmotogoozer]

This loose connector might be the wiring for the electric petcock. Your 2001 originally had an electric petcock but it appears that the previous owner swapped it for a manual one (good thing!). At least your petcock looks different from my electric one. If so, then that connector doesn't have anything to connect to anymore and isn't a problem. My money is still on the temp sensor.