High Idle, Pinging, Running Lean 2001 V11S

[moto fugazzi]

A few weeks back, I had my bike running perfectly when I went to Rosefarm Classics. TPS reset, TB's balanced, CO set, Idle at 1150, etc. AFR on my meter was at 13.1 through most of the range. 

The other day, my bike started running at 13.7AFR or higher, pinging at moderate throttle between 3-5k, and the idle has gone up to 1300RPM, and the spark plugs are white. The bike does seem to run fine in the warm up mode. 

The bike is still at 3.6 for TPS, and no sensor faults according to VDST and Guzzidiag. I did notice the air temp was at 96f, but the outside air temp was 60f. The bike had been idling for a while at this point, and the airbox snorkels are right above the engine, so with the bike sitting there, that could be normal?

What else could cause this sudden change? Possibly the crank sensor? I did clean it off earlier this year, and I don't know what the symptoms are when they go bad.

Once is a while, I can get the idle back down to 1150 when I blip the throttle, but then it does go back up. I did check for intake and exhaust leaks, and nothing seems to be obstructing the throttle or linkage. This also happened about the time I refueled, so I drained the gas and put in some fresh premium.

Any help would be appreciated.

Ken

[docc]

It would be good to recheck the temp after the bike has been moving or with a fan flowing air over it. The snorkels will pick up engine heat in still air.

 

Perhaps checking the variable resistance of the TPS. When mine went bad I couldn't find it watching millivolts, but it showed a stick-and-jump in resistance as I slowly opened it and closed it.

[moto fugazzi]

I did check the 2 temp sensors last night when I replaced the crank sensor with a used spare I had. They both seem good, and resistance changes when subjected to hot and cold. I'll double check the TPS tonight when I can finally fire it up-didn't want to do that last night at midnight. The TPS is about 2 months old, so it should be good. 

I wish I would have checked the new crank sensor before I put it on. The old one didn't change much in resistance when I put it next to a piece of metal. It did read 638 ohms without being next to another piece of metal, and the new one was about the same. It sucked changing that sensor since they routed the wire through too many objects. Any idea what the sensor should read next to a piece of metal?

Ken

[moto fugazzi]

OK. I rode around all morning yesterday to burn thru the tank of ethanol gas in order to fill up with real gas. Shortly after running on real gas, the bike started running perfect again. Makes me wonder if I just had 2 bad tanks of high ethanol gas (I think they use a "summer" blend in Wisconsin after memorial day) or if the tune up we did using real gas will make that much of a difference...time will tell after a few more tankfulls. 

 

I also hooked up a new air temp sensor before the ride yesterday. I didn't feel like taking off the tank, so I just plugged in a new sensor and zip tied it in place near the old sensor. I think I'll try Kiwi Roy's method of mounting the sensor up front away from the engine. I noticed that when I rode in city traffic at low speeds, the idle would climb up to 1400RPM at stop lights. It was down to 1150RPM when not doing slow stop and go city riding.

 

When I installed the stock airbox lid, I installed the snorkels facing down. Is that how they are from the factory? The bike had pods on it when I bought it.

Ken

[docc]

The factory snorkels do face down toward the cylinders. I have always held the opinion they were exclusively to damp noise for emissions drive-by testing and have always run without them. I could be all wrong about that, yet do like the full frontal area of the air box intakes without the restrictors.

[gstallons]

My snorkels are in this box on a shelf far away from the bike !

[moto fugazzi]

The factory snorkels do face down toward the cylinders. I have always held the opinion they were exclusively to damp noise for emissions drive-by testing and have always run without them. I could be all wrong about that, yet do like the full frontal area of the air box intakes without the restrictors.

I tried running the bike without the snorkels, but the bike always ran leaner the faster I went, so I put them back on.

I did move the air temp sensor to the front of the bike under the headlight, and everything seems to be good now. For the heck of it, I put the heat gun on the sensor, and the RPM's rose to over 1300RPM when the sensor went over 120f. Went back to 1150 when I cooled it down with a fan. Makes sense why I was getting the high idle in stop and go city riding. We'll see how things pan out over the next week or so.

Ken

[Kiwi_Roy]

I have an AFR on my bike, even well over 15 it doesn't ping on good gas, I try to use premium without ethanol.

 

I noticed my tach doing weird things when I turned the key on but not started, it would climb upscale

then drop back to zero. It turns out it was caused by the AFR, I suspect it draws a pretty hefty current

as it heats up from cold and the tach must be interpreting the current pulses as spark. I need to find

a separate source of 12V

 

PM sent

[moto fugazzi]

I have an AFR on my bike, even well over 15 it doesn't ping on good gas, I try to use premium without ethanol.

 

I haven't had pinging with real ethanol free premium gas yet this year, and the places that carry it are at least 45 minutes away from me. At least they're in nice riding areas once I get there.

I know you have MYECU. Have you adjusted the timing at all? 

Ken

[Kiwi_Roy]

 

I have an AFR on my bike, even well over 15 it doesn't ping on good gas, I try to use premium without ethanol.

 

I know you have MYECU. Have you adjusted the timing at all? 

Ken

 

No - I wouldn't know where to start, I have had enough trouble getting the mixture right, for a while I had a pot and battery wired up so I could adjust it while riding,

The AFR shows the ratio but then you have to figure out the throttle position and which cell it belongs to, I should have gone for the optimizer obviously but I didn't have an AFR when I bought the kit.

[moto fugazzi]

I had problems trying to adjust the PCIII based on the AFR as well. I ended up marking the throttle for the throttle percentage and watching the AFR to make corrections. It was very slow going and inaccurate (very slight difference between 5 and 10% throttle, not to mention the OEM Tach is off by a few hundred RPMs), so I ended up buying the LCD-100 display for the PCIII which shows throttle position, RPM, and the map adjustments. I then borrowed my friends GoPro to record the AFR and LCD display to create the perfect map. It's time consuming, but fun. I can also preload the LCD100 with several maps and change them as I ride. It's nice to have a performance map and a fuel efficient map.

 

Dynojet now makes an AFR meter that connects to the LCD-100 and PCIII so that everything can be monitoring on 1 screen, and you can record your rides and put all of that info into an excel file to build a custom map. The downside is that once you buy all of those components, you could have spent the same money on the PCV and Autotune.

Ken

 

Here's a pic of my experiment when I was using my iphone to record it. A little blurry, but useable.