oldguyinTX
New member
Dave, when the purge valve went on my 13 it had generally run like crap. It wouldn't idle properly, it would stall and then it was hard to restart.
My 13 had exactly the same symptoms.
Dave, when the purge valve went on my 13 it had generally run like crap. It wouldn't idle properly, it would stall and then it was hard to restart.
JC do you think the PV should be opening at a lower RPM as I do? Would that help the EVAP system? Why not random openings above 4k during acceleration? Personally I run between 5 and 6.5k rpms I almost always cruise at 5k on the dot and shift a little over 6k so it drops back to 5k as it does in every gear. It seems 5k in certain gears equals 35,45,55 mph.Glad they replaced your stuck purge valve which effectively plugged a good size vacuum leak. Nice that your bike is running better.
I can tell you without a single doubt that it did next to nothing for the gas fume issue. Its just the cooler weather helping that. It did nothing to lessen the heat applied to the fuel tank and thus nothing to lessen the quantity of vapors being generated when riding or stopped. The purge valve only opens above 5500 RPM, so effectively for a few seconds at the top of each gear shift. Its closed at idle and when the bike is parked. No place for the large volume of gas vapors to go.
Its too bad that you had to go through all of this just to get a simple stuck valve replaced so your bike runs right. There is really no praise to be given here. Very poor service from your dealer and BRP that let this problem go on so long. Its pretty obvious the dealer did no basic diagnosis before now. These are easy to find issues.
BRP still has a defective design evap emissions system to deal with on all 2010 to 2013 RTs. With the scrutiny the NHTSA is under for other lenient actions toward safety and emissions problems, BRP is dealing with this at about the worst time possible. When the data is in, the findings will likely be swift and severe. I project real action forthcoming before spring.
JC do you think the PV should be opening at a lower RPM as I do? Would that help the EVAP system? Why not random openings above 4k during acceleration? Personally I run between 5 and 6.5k rpms I almost always cruise at 5k on the dot and shift a little over 6k so it drops back to 5k as it does in every gear. It seems 5k in certain gears equals 35,45,55 mph.
I think it would help but at the lower RPM the unmetered air can cause driveabilty problems. I also think opening it at lower rpms, would be a drop in the bucket and not really fix much. It could never be opened at idle in the current EFI system.
Why couldn't it just be eliminated and made into a manifold vacuum setup that is constantly on? Isn't that the way it works on cars? Obviously it would need to be restricted more but a constant vacuum would make up for volume. Only down side I can think of is the boiling tank after shut down but a powered check valve could fix that too, Still thinking out loud.:dontknow:
Most cars use purge valves too. They are equipped with sensors so when they stick you get a check engine light, unlike the unmonitored one on the Spyder.
Problem with a continuous fixed bleed is that at idle and low rpm, the bleed with unknown quantity of fuel mixed in is a significant portion of the air needed for that engine load. Makes control near impossible. Most cars do bleed the evap canister at low engine load and just off idle, but the air being drawn in through the canister is taken from the intake track down stream of the mass air meter, IE its metered air. As long as the fuel air mix is in closed loop mode, the extra fuel is compensated for. The Spyder is a speed density EFI system. Not used in automobiles since the mid 80s. There is no mass air meter.
You are right about it never helping after shut down. But you cannot close in the tank either, with the amount of heat being applied the pressure would rise to the point of tank failure. Its only rated for a few ounces internal pressure.
No, the only answer is to remove the heat conducted to the fuel to keep it cooler and thus not vaporize. They can never design a proper system to contain the quantity of vapor currently being developed. The canister would be bigger than the engine....Well, I suppose they could install a pressure tank fuel system but it would be cheaper to just insulate the one we have or install an insulted one.
One advantage the Spyder owner does have is that the air charge temp is what is displayed on the dash. If we move the sensor, we can easily tell if it is reading cooler or warmer than before. In its current position, with the engine at operating temp, the sensor reads 5 or more deg above ambient. If we move the sensor and it reads cooler (closer to ambient) we know its an improvement. Cooler air charge will result in slightly richer mixture as the ECM thinks the air charge is slightly more dense.
Air charge does not effect fuel mix, only timing on most mass air EFI systems but it does on SD like the Spyder. Lets not turn this into a discussion on the benefits of MA vs SD in this thread. My comment on when automotive mfgs abandoned it was based on the Ford world but was not meant as an admonishment. Just that SD is what the Spyders use and what we need to be discussing here if we want to engineer a better solution. I really like where this conversation has gone.
What I would like is for someone familiar with the connector types involved could build an extension cable for the charge air / barometric pressure sensor so we could try other locations. Finless? You out there? This has your great capabilities all over it...I have no problem being the guinea pig if someone can build a cable. I don't recognize the connector or know where to get one each male and female of that type.
Within your experience, would it just be best to install / relocate the pressure temp sensor to a location within the airstream just prior to the air splitting for each throttle body bore. Such a location would be the airbox. This would be the truest indication, and most stable point to collect data for the ECU.
Since most people do not appear to understand the difference between the two SD vs MA, it is good to understand that SD is a good system on a performance vehicle. No comparison.
Air charge does not effect fuel mix, only timing on most mass air EFI systems but it does on SD like the Spyder. This is quoted from your post. The wording may be confusing to others new to engine tuning.
I must ask, within reason, in the quest for an optimum location, what verification is there to ensure proper engine parameters are met beyond seat of the pants? Again, and I realize I am basically exempt since we ride a 14, but if the 14 1330 is measuring pressure and temp just downstream of its single throttle body, wouldn't the best setup be installing the pressure temp on a v twin be just prior to the throttle bodies and having some form of aftermarket tuning aid to ensure mixture ratios and tune them if needed?
As for the extension harness, if the testing involves multiple relocations to optimize the location, maybe sliding the sensor into the intake duct work of the front bodywork and show the real temp of air entering the airbox may be a place to try.
PK
Like I mentioned the recent test bikes for BRP's heat fix had the sensor moved I believe. Now would be the time for one of them to chime in. I kinda agree with SD being the preferred choice simply because one less variable is eliminated from the tuning process making it a bit less complicated. Is it better? eh apples and oranges. :dontknow: All I can say is it was why I went with 2 early LT1 cars the system I was more familiar with.:thumbup:
JC, when I posted this in a previous post, the words "no comparison" was meant to mean I am not comparing as you requested. I was not saying the SD is no caparison better than MA.
As far as mounting in / onto the airbox above the throttles. After giving it more thought, it may require some additional tuning since it is downstream of the air filter and may see fluctuations from throttle changes.
Maybe a better location is in the oem air filter box on the unfiltered side. This may be the truest temp and lowest airflow of the induction system including the airboxes.
Just ideas, nothing carved in stone.
PK
Sorry, I misunderstood.
I think the air box upstream of the filter or in the air inlet duct just before the air box would work but do not know how the current sensor is configured to deal with air flow near its sensor point. The new sensor installed as part of the heat fix could be the same except for mounting and inlet configuration. Still, mounting it there would require a harness extension I think. Not sure it would be worth the effort over just moving it out of the heat like BRP is suggesting in the heat fix trial.
Air inlet upstream of the air box is where its located on my truck. Air inlet between the air filter and the throttle body is where its located on my GT. Both are temp only, manifold pressure sensor is independent.
Getting nasty. I was only posting information that may/or may not be beneficial to other folks on this forum. Yes, the :ani29: is still under warranty. And no, I do not know what a new, empty Evap canister weighs, but I'll bet you do. Please let us all know, so we can make a comparison test verses what is on our :ani29:'s. Oh, wait, that would require removal of the canister & the purchase of an accurate scale. Anybody out there got one that you are willing to lend/rent?