Oil Temp Sensor Disconnected

[Scud]

I noticed yesterday that the oil temp sensor (the blue plastic thing on the RH head) was disconnected. The connecter had been taped against the wiring harness. So I freed it and plugged it back in; everything seemed fine for a ride around the block.

 

I just picked up this 03 LeMans a few days ago, which was running very nicely, but had clearly had some electrical mods.

 

This morning, I rode it to get gas and then to work (less than 10 miles total). Between the gas station and work I experienced these two new problems (which I did not have before plugging in the sensor, and after the bike was fully warmed up):

1. Harsh hiccup at idle
2. Oil light came on at idle (about 1,000) - but went out when I increased it to about 1,400.

Other things that might be good to know:

• K&N pod filters installed by PO
• I replaced the rubber caps over the throttle body balancing tubes (the ones on the bike were badly cracked)
• Full tank of premium gas
• Oil level is slightly above the maximum mark on the dipstick (and oil looks clean enough, not old)

Here are my short-term questions:

1. Does a disconnected sensor indicate another problem that I should be aware of?
2. What are the side-effects of running with the sensor disconnected? (I assume I should unplug it to ride it home, because it runs great unplugged)
3. Is there an obvious solution? (feel free to paste a link to an appropriate thread instead of repeating information)

Longer-term - I'm going to go through the whole bike and get it sorted out.

 

BTW - Sorry for starting a new topic on this.  I found another one on this topic, but it was locked after 58 pages of... well, I'm not sure what to call that, but I'm glad I missed it.

[czakky]

I could be wrong but I think the higher the oil temp the leaner the fuel-air mix.

 

Do not ride that bike with the oil light going on! Pull that sump and make sure your oil filter is tight with only one gasket on the filter.... Dude I'll pay for your oil! That sensor detects very low pressure. Pull it off and blow on it you can hear it trip, takes next to nothing.

[czakky]

Oh yea the oil sensor topic....

[Scud]

Thanks - I think there are two oil sensors.

1. for pressure - which sends an on or off signal to the dash light, and
2. for temperature - which sends info to the ECU.

Since this bike has the pods, I assume the sensors have been "tricked" to make it run well.

 

Fear not, I won't ride with the pressure light on.  I will give it a thorough inspection/fluid change.  But thought I could sneak in a few commutes and little joy-ride first.

 

Unless there's another cause for alarm, I'm going to pull the oil temperature (not oil pressure) sensor plug off again and ride it home.

[Kiwi_Roy]

There is one other sensor, the air temperature. This was in the original air box. It may be tucked up under the tank somewhere which is too hot, it normally operates in the cool intake air. I moved mine up to the headstock when I put pods on. Perhaps it's compensating for no oil temperature (isn't it really to measure engine temperature?)

 

The pressure switches are notoriously unreliable so it's possibly going off early. I have a pressure gauge on mine mounted to the steering damper bracket, it's a great re-assurance.

Connecting the sensor would have no effect on oil pressure.

Unless the bike has a Roper plate keep the level near the high mark, the pressure on mine will drop to zero on acceleration if I let it get low.

[czakky]

Sorry Scud, wasn't trying to go panic mode on you buddy. All I'm saying is that if I was the last person to change the oil, okay I will accept that it could be a false oil light under low rpms.  If I haven't dropped the sump to see what it looks like I might worry. That being said if K_Roy says these switches are unreliable...well he knows better than I do

[Kiwi_Roy]

Hey Czakky, I agree with you I wouldn't ride it either, not without a gauge to verify it has some pressure.

The last switch I bought lasted less than a month before it went off permanently.

I spec out instrumentation as part of my job, the operating parts of these switches is too small for the low pressures involved IMHO

If you look at the equivalent switch in a car the working parts are probably 10 x the size.

[czakky]

That's interesting. Didn't somebody find a Honda Civic pressure sensor that worked for our bikes?

[Scud]

I disconnected the sensor and made it home without event. I figured that it was running great before and it would get me home, but I did watch those lights.

 

I appreciate the cautions (and I understand that nobody wants to be the guy who says "just ride it" after the oil light flashes on). It's like telling a guy with chest pain that it's OK to skydive...  That being said, she was naughty today and has to sit in the corner for a time out (for fluids).

 

A quick search for "Honda Civic" didn't produce the replacement sensor. 

 

Moving off-topic - is there a list of cross-compatible parts and supplies somewhere on this site?  Things like an automotive oil pressure switch, Isuzu Trooper fuel filters, aftermarket spark plug caps, etc.?  A list like that could be handy.

[docc]

Moving off-topic - is there a list of cross-compatible parts and supplies somewhere on this site?  Things like an automotive oil pressure switch, Isuzu Trooper fuel filters, aftermarket spark plug caps, etc.?  A list like that could be handy.

SHeesh - I thought you guys were going to give me time off for good behavior . . .

 

Unplugging the Head Temperature sensor looks like a bogus attempt by the PO to dodge the complete tuning necessary to get these bikes running well. Agreed, look inside the sump, especially at the status of the filter and the condition of the mesh screen.

[sculler2x]

I replaced the pressure switch with the one on my BMW R100.  The only change I had to make was replacing the bulet connector with a spade connector; a 5 minute job

[vuzzi]

I'd take the sump off, remove the oil filter and check if rubber ring comes off completely. Then replace the oilfilter and the oil. Fill the filter with oil before puting it on. Put it on thightly.

 

The oil/engine temp sensor off will make the bike run richer. The tps has probably been adjustet to this setting.

Put it back on and re-adjust the tps:

http://www.v11lemans.com/forums/index.php?showtopic=12204

 

You might also want to check the maps using guzzidiag:

http://www.v11lemans.com/forums/index.php?showtopic=17865

[Scud]

Thanks for additional ideas. I've got the bike partway disassembled at the moment. After I clean it up, I'm going to put the stock airbox back on and go through the whole tuning procedure. The air sensor had been relocated between the cylinders. I will also install a new oil pressure switch. We'll see how she goes after all that.