M7 sounds like it’s hitting a rev limiter

I would also check the power valve cables and the servo actuator, the RPM you stated is right around the point where the valves open up.

Some info I pulled from the Quick Links at top of page:


Rough running M7- APV
check to see if the servo motor, behind the pipe in the square clear cover with two cable coming from it to the exhaust valve, it should cycle at 3800 to 4000 RPM. by cycle I mean you will see the motor turn and the cables move. Check to see that the cables move freely, running a poor grade oil will stick the valves and cause them not to function. Check all the lights pull the brake and see that the lights and speedo don’t go out; if they do you have a pinched wire under the tail light cover, in this case the blue wire.

Exhaust valve symptoms-
05 M7 wont rev up over 6800 r's? think the check engine light is what’s not allowing it to rev up but why is the check engine light on? Also there was some extra oil in the air box.
Is the check engine light on steady or is it flashing?
If it's flashing, count the flashes and check that against the sticker under the hood. Might give you an idea of what’s wrong.
Happened to me. Power valves were sticky and the cables popped off servo motor.
it was the power valves.

Exhaust valves servo-
lost top rpm on this sled, like hitting a rev limiter, sled will see 7920 but motor starts surging and cuts out but holds 7200 rpm but has the surging going on....best explanation is it is acting like a rev limiter or stutter box.
It is the servo. If the cable free play is to short and the motor can not pull the full range of motion it will flutter a few times and then just stop working. It will re-set when you start the motor again and will do it over again.
You need to have an extra guy to look at the servo while you run the sled. Take the cover off the servo and run the sled to 7200 it should snap open and stay open. If it opens and closes you need to lengthen the free play. It sounds like it will open close open close open close and then stay closed. This saves the servo from burning out. Make sure the primary clutch side is on the front of the servo.
May be the APV DC- Power diode that is in the voltage reg. Only four thing to look at, wiring,ECU, voltage reg, servomotor, red/blu wire out of the reg is DC power to the ECU for the APV.

Power valves- check adjustment length
I have a 2006 (early build) Crossfire 700 that won’t pull over 7300-7400 RPM. I’m at a loss of what is causing this; it was running really good and now this. HELP!
Sounds like the power valves are not opening. That’s about all the higher she’ll pull if the valves stay in the closed position. On the EFI models (like yours) the servo doesn’t cycle at start up like on the carbed models, so lift the rear of the sled onto a secure stand and run it up past the valve opening RPM (past 7000 RPM) and see if the servo motor cycles. Check to make sure the cables haven’t popped off or something stupid, if the vales get gummed this could happen. My guess is the servo motor isn’t getting the signal to open (a connector/wiring issue) or the servo motor itself went south. There is a position sensor inside there that could’ve went bad, so if the motor (pulley) doesn’t move at all after reseating the connectors try a new servo. If that doesn’t work, you’ll have to verify continuity from the ECU to the servo. I doubt it is an ECU problem; it’s either the servo or the wiring

https://www.snowest.com/forum/showthread.php?p=1956115#post1956115


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