M
Well that's good to know. If you disconnected the taillight harness would that eliminate or confirm the possibility of a short if their was one?
05 M7 won't rev past 6000 rpm
- Thread starter Mx21
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M
Well I unpluged the taillight from the wire harness and it still won't rev to full rpms. So a short should be ruled out. However I retested the coil and it read .6 ohms which according to the manual it's suppose to be .24-.36 so it reads almost double what it should be. Could that be the problem. My thought would be if that is the problem and the resistance is too high would the spark not get hot enough to burn all the fuel on the top of the rpm range? I don't know I'm just spit balling here
Someone else mentioned checking your tail light wiring. As I understand it, it needs to be hooked up, disconnecting it won't eliminate the problem. If it is your tail light, it may already be disconnected somewhere causing you the problem. I'd do a continuity test on the wires from the engine back to your tail light. Right behind your muffler they go thru a hole in the bulkhead and sometimes wear there. If that checks out, then I'd look real close at where they go into the tail light. Maybe you've already looked and checked all this but it's worth checking if you haven't.
Something else, does the pto and mag plugs look similar as far as fuel mixture? You said that one was spitting fuel out and the other wasn't so maybe for some reason you are really rich on one and lean on the other?
With the machine running, have you sprayed some carb cleaner around the cases, reeds, and throttle bodies to see if you get a change in rpm? If so you have a bad gasket or an air leak.
Have you checked the reeds? The petals could be chipped or damaged.
Something else, does the pto and mag plugs look similar as far as fuel mixture? You said that one was spitting fuel out and the other wasn't so maybe for some reason you are really rich on one and lean on the other?
With the machine running, have you sprayed some carb cleaner around the cases, reeds, and throttle bodies to see if you get a change in rpm? If so you have a bad gasket or an air leak.
Have you checked the reeds? The petals could be chipped or damaged.
M
Well I didn't completely check the taillight wire so I'll check that along with spraying some carb cleaner in the carbs while it's running. But is it possible that the tps or the coil is cause more fuel to go to one cylinder than the other?
M
Well my dad pulled the boots off of spark plug caps and he said that the wire was a little corroded. So if that's bad could it cause it not to pull rpms?
M
Today I started throwing parts at it. I put on a new coil with new spark plug caps. Put on different throttle bodies off a running 05 F7 eff (with injectors and tps) And the was no change in how it ran. The only thing I can I think of that hasn't been change or checked is the ignition timing sensor, stator, and the fuel pressure. Anyone have any thoughts as to what it could be anymore?
your tank venting ok...or no pinched fuel lines...
how about your barometric tube on ecu...no kinks or moisture..
how about your barometric tube on ecu...no kinks or moisture..
M
The fuel lines are good and not kinked and the the tube coming out of the ecu looks good and clear no condensation.
100psi at low elevation....that many miles on the engine....might just be low on power and ready for a rebuild?
Do you have some lighter clutch weights to try? If that shows more rpm that would indicate a power loss.
I wouldn't bother looking at rpm on the track stand, dangerous and doesn't really mean much without any load.
Do you have some lighter clutch weights to try? If that shows more rpm that would indicate a power loss.
I wouldn't bother looking at rpm on the track stand, dangerous and doesn't really mean much without any load.
he didn't do a proper compression test with throttle open etc...so it may or may not be low..
but that's a great suggestion on the weights
but that's a great suggestion on the weights
M
But if it was the engine that what was about to blow up wouldn't it just not make enough power? It runs great up to 6900 rpm if you hold it half throttle it doesn't stumble or anything but if you hold it wide open it sounds like a rev limiter. however randomly it hits full rpms briefly. and the weights in there now are for 9000+ ft and those are the lightest i have.
no where can I read that you put new plugs in..?? and if you did if they are they resistor type...
and did you or did you not pull connections apart and use dielectric grease...and did you or did you not trim a quarter inch off your high tension leads..
these were all suggested and not confirmed by you...??
and did you or did you not pull connections apart and use dielectric grease...and did you or did you not trim a quarter inch off your high tension leads..
these were all suggested and not confirmed by you...??
M
I did not use dielectric grease when I put the new coil on nor did I use new plugs in but the plugs were the first thing I tried when it started acting up. I did trim the high tension leads back 1/4 of an inch and then electric taped the caps after i put them on all the way. the number of the plugs are 7548-BR9EYA thhey are NGK plugs.
I am talking dielectric grease on all your plug connections...ecu etc etc stator etc etc...and im saying NEW plugs...so I assume your answer is no...??
and did you look at all the plug connections for bent or pushed back pins..??
GET TWO NEW PLUGS IN IT...PLUGS WILL FAIL UNDER LOAD AND SPARK ALL DAY WHEN NOT UNDER LOAD..!!!
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M
I have a ton of extra plugs so I'll throw so new ones in tomorrow morning. Also i got got dielectric grease laying in the shop somewhere so I'll do that as well. other than that i was thinking of checking the fuel pressure and see if thats within spec.
PS...are both plugs displaying same color...one wet one dry...one brown..one black..??
again get new plugs in..i will send ya the ten bucks for them...lol..
again get new plugs in..i will send ya the ten bucks for them...lol..
you said in your first post you checked fuel pressure and it was in spec..???!!!
willikers kid you have to throw us a bone and then make sure it can be chewed..!!!!
you just thank your lucky stars I wasn;t a teacher of yours in high school..you saying one thing and not meaning it..lol..
start with the new plugs in the morning..
M
Haha I know but I my thoughts kinda get jumbled when I try to explain stuff. but yes the fuel pressure was checked last fall the guy that did it said it was good but i would like to double check it again. I've had this problem for about a year but With college and working out of state its been hard to find time to work on it. Again thanks for the help I really appreciate it.
M
Almost forgot as far as what the plugs look like I don't remember but I look in the morning and find out