Hate to tell you this but misfireing still remains.From standing still and WOT
it misfires badly.Thougt it was the carb hoses but apparently not.
From 7000 rpm and WOT it pops 4 to 5 times and then hits 10300 rpms.
I´ve cleaned the pilots but have I cleaned it properly?
What rpms are the pilots working on?All hoses are ok .Could it be sparkplugwires?
Worse of all ,could it be the gp-1 exhaust with its restrictive backpressure,gues not because wastegate working ok.
It´s not the TORS,wired through,or the wastegate wich would pop all the way with its carictict sound.
Help...
it misfires badly.Thougt it was the carb hoses but apparently not.
From 7000 rpm and WOT it pops 4 to 5 times and then hits 10300 rpms.
I´ve cleaned the pilots but have I cleaned it properly?
What rpms are the pilots working on?All hoses are ok .Could it be sparkplugwires?
Worse of all ,could it be the gp-1 exhaust with its restrictive backpressure,gues not because wastegate working ok.
It´s not the TORS,wired through,or the wastegate wich would pop all the way with its carictict sound.
Help...
This is not a joke, but do you have higher wattage headlamps?
High wattage lamps can make it misfire under load. :!:
High wattage lamps can make it misfire under load. :!:
Buckeye
Lifetime Member
- Joined
- Apr 13, 2003
- Messages
- 1,430
- Location
- Lakes Region, NH
- Country
- USA
- Snowmobile
- 2018 Sidewinder LE XTX 137" 50th Aniversary
Misfire
I had misfirw and a wicked low end bog because the vent hose from the metal T to the lower intercooler inlet was kinked. That clear plastic hose is no good. It gets too soft from the heat and bends and kinks easily causing a lack of fuel pressure and lean condition. Although mine ran fine once it got going. MXZ is right about using too much electricity screwing up the CDI, not enough power left for it. Try turning your handlebar warmers off and see if that cures it. I think it is a fuel pressure problem. Not sure where though.
I had misfirw and a wicked low end bog because the vent hose from the metal T to the lower intercooler inlet was kinked. That clear plastic hose is no good. It gets too soft from the heat and bends and kinks easily causing a lack of fuel pressure and lean condition. Although mine ran fine once it got going. MXZ is right about using too much electricity screwing up the CDI, not enough power left for it. Try turning your handlebar warmers off and see if that cures it. I think it is a fuel pressure problem. Not sure where though.
I have the same charged as before,never changed a bulb what so ever,only thing changed is gp-1 exhaust.
Could it be(godforbid)some kind of mechanich messup?I do most of my mechanic changes all of myself except of the 4-strokes.
One friend told me,check the plug wires.I will do it tomorrow.Thanks!
Could it be(godforbid)some kind of mechanich messup?I do most of my mechanic changes all of myself except of the 4-strokes.
One friend told me,check the plug wires.I will do it tomorrow.Thanks!
SUPERTUNER
TY 4 Stroke Master
Hooper...check the fuel pressure and make sure it is set at the MCXpress recommended pressure.
Also, make sure you are not hitting the rev limiter when throttling up. If it spools up quickly and really wails, it might be tagging the rev limiter. The only other thing I would recommend...and this is quite serious is to make absolutely certain you have enough fuel for the engine to survive on. Turbocharged engines break up when they are building boost that is not properly fueled. This leads to detonation and detonation leads you nowhere!...fast!
This is why I want you to check the fuel pressure. Raising fuel pressure also enrichens even without a main jet change (to a point).
One last thing you could try if you are running pump fuel is to switch to race fuel suited for a pressure environment..i.e. Turbo/nitrous etc. This will curb detonation and even if you use this good fuel and the performance drops but the popping stops, you will then know it is detonation causing the breakup.
Keep us posted on how you do.
Freddie
Also, make sure you are not hitting the rev limiter when throttling up. If it spools up quickly and really wails, it might be tagging the rev limiter. The only other thing I would recommend...and this is quite serious is to make absolutely certain you have enough fuel for the engine to survive on. Turbocharged engines break up when they are building boost that is not properly fueled. This leads to detonation and detonation leads you nowhere!...fast!
This is why I want you to check the fuel pressure. Raising fuel pressure also enrichens even without a main jet change (to a point).
One last thing you could try if you are running pump fuel is to switch to race fuel suited for a pressure environment..i.e. Turbo/nitrous etc. This will curb detonation and even if you use this good fuel and the performance drops but the popping stops, you will then know it is detonation causing the breakup.
Keep us posted on how you do.
Freddie
slims427
Newbie
- Joined
- Dec 2, 2003
- Messages
- 23
misfire
This sounds silly but try running with the low beam on and your hot grips down low. I bet you are low on voltage. You have only 40 watts reserve with nothing added. Slim
This sounds silly but try running with the low beam on and your hot grips down low. I bet you are low on voltage. You have only 40 watts reserve with nothing added. Slim
Buckeye
Lifetime Member
- Joined
- Apr 13, 2003
- Messages
- 1,430
- Location
- Lakes Region, NH
- Country
- USA
- Snowmobile
- 2018 Sidewinder LE XTX 137" 50th Aniversary
Electrical Problem?
I am probably running as much electrical stuff as Hooper with the same setup and no misfire problems. I have higher wattage bulbs and 2 guages, warmers, G-tech, etc.. I think it is fuel pressure. Hooper, you didn't mix up the jets, did you? If not, it is a blocked vent or kinked hose.
I am probably running as much electrical stuff as Hooper with the same setup and no misfire problems. I have higher wattage bulbs and 2 guages, warmers, G-tech, etc.. I think it is fuel pressure. Hooper, you didn't mix up the jets, did you? If not, it is a blocked vent or kinked hose.
thebest
Pro
you need more fuel. youre too lean, i have a turbo kit and i've got 145 main jet and the needles at 4. before putting bigger jet make a lot of backfire. turbo need some fuel. thebest
thebest
Pro
install a air/fuel ratio meter and you see what happens.
Found one thing:Opened the fuelcap to fill her up and air swooshed in/out :shock: could a kinked vent.hose to the fueltank cause this problem?Havent had time to test today.
Buckeye
Lifetime Member
- Joined
- Apr 13, 2003
- Messages
- 1,430
- Location
- Lakes Region, NH
- Country
- USA
- Snowmobile
- 2018 Sidewinder LE XTX 137" 50th Aniversary
Misfire
I would think that this might prevent fuel from flowing. I hope this was your problem.
I would think that this might prevent fuel from flowing. I hope this was your problem.
Yes that could very well be the problem. :idea:
I have seen this exact problem on two other sleds, both with turbo, and both times it was a kinked fuel hose. Unkinked it and problem was gone! Good luck with the problem hooper.
Problem solved 
It was the ventline in top of fueltank that was totaly bent :!: Hard to find witout a flashlight.Now throttle response is as crisp as it used to be.
Thanks to you all for the tips :lol:
It was the ventline in top of fueltank that was totaly bent :!: Hard to find witout a flashlight.Now throttle response is as crisp as it used to be.Thanks to you all for the tips :lol:
