Temperature Display Problems

[jfz6]

I recently posted an article about gas mileage as I am only getting about 120 to 150 miles out of each tank. I noticed last night that it was 29 degrees and for some reason I always check the temperature to see how accurate it is.

Last night when it was 29 degrees outside the bike said it was 50 and I had just turned it on and had not ridden it all day.

Today it said it was 79 degrees outside and when I got home the weather said it was about 49 degrees.

So all of a sudden when my bike is cold it is about 20 degrees off and when I am riding it goes to being about 30 degrees off.

Does anyone know what is up with this?
Is the fuel indicator and the temperature indicator both controlled by some electronic computer and it is just out of whack?

Any help would be nice as this is an 07' with 1400+ miles on it, still under warranty, etc.
J.

 

[trailblazer87]

If the computer thought it was colder than it really is, then it would keep the mixture richer than it should be because cold air is denser than warm air. This sounds like a warranty issue to me. There is a sensor in the air box that detects the air temp. along with the air pressure, this is how it adjusts the air fuel mixture. If you are running rich then your mileage would be worse. Is the motor running hot or cold? Does it stumble when you hammer the throttle at low rpms? Does it pop or backfire on deceleration? Does the exhaust smell funny? Can you see the exhaust after the motor warms up? Does it feel like its missing any power?

 

[jfz6]

Actually the computer is saying that it is 20-30 degrees warmer than it really is. How serious is this issue? I am new to bikes (3months) so it smells funny from time to time. The weather here has been crazy 29f at night 65f during the day plus the humidity is all over the place. It also sucks because I park my bike outside. Maybe I should have it checked but then I am without a vehicle....hmmm.

 

[jfreakman]

You know, its funny, i kinda worried about this when I got my '07. I would ride in 80 degree weather and it would say it was 92 outside.
Someone passed this info along to me, it makes sense and my bike is still running fine. You will have weird smells with a new bike.
The "A" temp doesn't stand for ambient temp, it stands for airbox temp.

The airbox is right behind the radiator, which has air blowing through it while the bike's running. The radiator pushes hot air into the air box, which raises the airbox temp and the reading.

 

[DefyInertia]

Did no one mention that the temp guage does not measure oustide air temp...? It usually reads 10 to 30 degrees higher than the ambient air temp.

 

[jfz6]

Ok. I usually always check the " A " temp when I first get on my bike and it is almost always spot on +/- a few degrees because I check it when the bike is cold and has not been ridden.

Example: It is 56 outside. I turn the key (without cranking it) and check the "A" temp. It will usually say it is 56-60. When I ride of course that changes.

If it is sitting still then the ambient temp and the outside air temp should be the same.

I just got on it a little while ago. It was 49 and the bike (cold) said it was 75. The "c" temp went from low and started climbing but started to drop as I got going a little. I went about a mile and then let it sit idling for about 15 min. and it climbed to 201 on the "c". "A" only went up to 77.

I started riding and in the mile I went the "c" dropped back down to 180. So now I am going to get out on the highway and get going a decent speed and ride a bit and see how much the "c" drops.

The bike seems to be running fine. Thanks for all the help everyone.

So many questions, so many questions.

 

[jfz6]

Oh! I will check the green wire...God Help ME!....but we did have a huge storm the other night with some tornados and extremely high winds. I have not thought about it but I have not ridden it since. The rain was crazy bad ( going sideways) and there sat my poor bike out in it uncovered. Could this have something to do with it?

 

[jfz6]

Alrighty! I posted the post two post up about 10 minutes ago. I just went to get on the bike. The "c" temp has dropped to 153f. The "a" temp has climbed to 93f! It is 49f freaking degrees outside? What gives?

 

[jfreakman]

okay, well that's definitely a huge jump. There may very well be something wrong with your bike

 

[trailblazer87]

"C" temp is water temp. "A" temp. is airbox. Water temp sounds normal. Something wrong with the airbox sensor though.

 

[Botch]

Hmm, temp displays must've changed somewhere along the line. My '07 doesn't have an "a", "b" or "c"; it defaults to one temp every time I start it, the coolant temp. It won't even display the temp until 108 F or so, below that it just says "Lo".
If I press and hold one of the two buttons (I can't remember which one offhand and its dark outside now) the temp toggles to the airbox temp; I always thought this would be equivalent to ambient but one poster above says that airbox air flows thru the radiator first; this makes sense.

 

[Bo67]

Yep. Your coolant temp (C) sounds ok to me. If the temp goes to 201 then you start riding and it goes to 180 that sounds good. It will do the same thing just sitting on the centerstand and revving the engine (mine goes down 5-7 degrees when I do this). That's just the water pump circulating the water (and dissapating heat) quicker through the system than it does at idle.
The "A" reading is airbox temperature (Botch; you may have heard of the term "air inlet temperature" on jet engines). Pretty much the same on bikes and cars as on aircraft; it basically sends the temp signal to the engine control/ fuel control unit so that it can schedule the correct fuel metering for optimal combustion at various temperatures.
IF the engine is cold and your temp reading is 20 degrees high, I would have the dealer take a look at it. My gauge reads right about what the ambient temperature is when the engine is cold. When my engine is warm, my airbox temp reads ~10-15 degrees higher than the ambient temp.
Hope it all works out for you.

 

[madmanmaigret]

My gas mileage ranges in the same area (120~150 per tank) which averages out to about 40mpg. so are we saying this is not normal? I always though it should be higher but it is still fairly new. I haven't really checked my air box temp because I thought it was just a semi-useless feature. Ill have to check it out.

p.s. I do mostly city driving and I do like higher rpms (just like my fz6) so I figured this played into my gas mileage also.

 

[HavBlue]

Did no one mention that the temp gauge does not measure oustide air temp...? It usually reads 10 to 30 degrees higher than the ambient air temp.

Yup and it is likely the temperature you see on the display will never be the same as outside or ambient temperature. The other issue hear is where the temperature (ambient) is being taken and if that temperature is taken under the same conditions as that of the sensor. The temperature on the display is air inlet temperature and it is shrouded where the temperature taken by the likes of a RAWS system for weather is not. The ambient temperature for weather is also effected by the elements where the sensor is not. If you fire that bike and let it warm up then shut it off things will likely be way off because heat rises and it will rise right up to that sensor. So, for use as a gauge to outside ambient temperature the sensor on the bike is not reliable at all because this is not what it is there for.

Now, as far as the fuel range goes, I sure would like to see an honest 100 mile fuel run on this bike. No throttle jockeying, no screwing around, just an honest steady state two way fuel run. That will tell all...

 

[jfz6]

When I got back on the Bike last night right after my last post the "c" temp had dropped back down to about 154. However the "a" had jumped to about 98f SO I WAS REALLY FREAKIN OUT! I am mechanically challenged so I didn't see the green wire either.

I wanted to see what my idle RPM's were for the poll after reading that one and I needed to fuel up so I decided to take about a 15 mile detour to see how it was running. It was running just fine.

Now for no apparent reason it is working just fine.



only dropped

 

[dark_isz]

..........

 

[RobberRog]

My FZ's airbox temp guage reads 41F or 47F no matter how hot or cold it is. It runs great, but the airbox guage seems useless.

 

[alanrim]

The airbox temperature has already stated is not ambient, the only time it should read anywhere near the ambient temperature is when the bike has been stood in the shade for at least 12 hours.

I get around 40 to 50mpg out of my 2008, basically I have always gotten around 40mpg from all the bikes I have ever owned.

Our gallon is a larger volume than the US gallon, therefore getting 40mpg in the states sounds fine.

I am sure you could get it up to 60mpg but that would mean being real gentle with the acceleration/braking.