01-26-2011, 07:23 PM #1
Need advice: FZ running lean at WOT after reflash / miss at idle
Looking for some input here guys. Sorry the post is so long, but if someone could take the time to take a look I'd appreciate it.
Here's the scoop:
Broke the ski in the Greenhulk method, everything was fine. Idled great, didn't get any AFR's didn't feel like I needed to.
Pretty much did all the mods at once (RIVA I/C, intake, mani upgrade, exhaust, etc) R1 and went to a C1 wheel. Didn't get AFR's (which was a mistake) and noticed at idle was real rough which feels like a miss, and started to have some hesitation when going from idle to any RPM. Anything past idle though it ran smooth as buttah.
Figured it was the plugs so I changed them out and decided to go C3 at the same time as well.
So here I am now!
Got AFR's today with the LM-2. I feel it's reading fairly accurate as I checked ambient air and got 20.9.
idle: 13.2-14+ (because of miss?)
8100 which is my WOT (using an ebay cheapie tach) 13.5
I just don't get why it's so stupid lean at WOT. I mean the powershot may be needed to fine tune your AFR's, right? Should it be in the ballpark at least?
The other thing to is the miss at idle, any thoughts on this? It still runs smooth anything past it. I can't help but think it may be related to the lean condition.
I'm gonna pull the plugs tomorrow and put some pics up too to see what you guys think.
Thank you fellow Hulksters
01-26-2011, 07:28 PM #2
Which reflash did you get & what Powershot settings (RED) are you using for the C3?
01-26-2011, 07:46 PM #3
01-26-2011, 07:50 PM #4
Your hesitation off of idle is because you are lean. The miss,,,maybe.
01-26-2011, 08:00 PM #5
Also, I'd disconnect and then reconnect all injector fittings.
01-26-2011, 08:14 PM #6
For me, your readings don't seem that far off from what I've seen on my ski when it was running its best. Is your idle AFR of 13.2-14 after warm-up?
Don't know if you remember this thread.... http://www.greenhulk.net/forums/show...=132634&page=1
01-26-2011, 09:27 PM #7
Bill, that Riva cooler really leans things up. Looks like you're gonna need a PS or FPR. Mine was borderline after installing that IC, even with the stock wheel.
Mine has always idled rough since installing the R2. It smooths out a little once the engine wars up but it seems the SHO engines needs to be kind of fat to idle smooth.
from my rebuild thread:
01-26-2011, 10:03 PM #8
Those AFR's don't sound terrible to me. I think everyone here forgets that 14.7 is what is considered the "Normal" AFR when it comes to what all vehicles (are supposed to) run at as a factory setting to pass emissions. That is where there is the most fuel burned (the least bad emissions) without being too lean. Now keep in mind that we do want to be safe, so it is preferred to run in the mid 12's to 13's. 12.5 is fairly rich and good for boosted motors. You can go richer, but it's going to start fouling out if you don't have load on the motor. Idle has "no load" so it is 100% fine to be 14.7 and will not hurt the motor whatsoever. To be "safer", yeah you could be running more in the mid 12's. It would probably be better if you were seeing it a bit richer at 8100. Unfortunately to really know if this is an issue, you would have to know if the exhaust is getting too hot (EGT) and also if there is an "knock". I don't know if there is any way to know this from the Yamaha logs. Anyone? I've been told that the Yamaha ECU's have very good knock sensors in them, so you would probably only "feel" reduced performance if it was starting to detonate.
Now when you pull the throttle, if there is a hesitation, that is more likely something wrong with the mapping in the ecu. Whenever you apply throttle, whether it is a car or a ski, the ecu should give an extra shot of fuel to get things rolling (what in the carburetor days was called the "pump shot"). My guess is that there is not enough pump shot in the R1 for your ski and that is why you would have a hesitation.
01-26-2011, 10:08 PM #9
Thanks for the replies, men. All comments welcomed.
Will do on the injectors.
01-26-2011, 10:15 PM #10
You know, give Glen a call at R&D with the AFR numbers. He should be able to tell you better than us if they consider those "safe" numbers (they've done lots of testing). My guess is that he will think most of it is fine, with the possible exception of the 8100 rpm. Also tell him about the hesitation and see what he says. Please let us know what he says.
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