I'm new to the honda world and was wondering if the vtec can go out on a motor?
vtec
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RedRacer
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Yes, VTEC can "go out". The whole process for the engaging of the VTEC mechanism relies on many, many things.
Reasons that it will stop working range from CEL codes to faulty VSS-speedo readings, and/or a tachometer that isn't working correctly, low oil pressure or even oil that's old and thin...bad coolant temp sensor, faulty VTEC solenoid, VTEC pressure switch that's bad...the list goes on.....
The VTEC mechanism is operated via hydraulic pressure, hence why you see that I have listed so many of the problem sources as being oil related. VTEC is very much affected by oil/oil pressure related matters. At low speeds the oil flow is closed off from a valve via the VTEC solenoid pressure switch which allows the hydraulic pistons in the rocker arms to operate independently - no VTEC engagement. At high speeds (VTEC engaged) the pressure switch allows the oil into the passage which causes the hydraulic pistons to lock the primary, secondary and mid rocker arms together. Hydraulics being the key actuator of the mechanism, so oil is where the hydraulic pressure is derived. Oil problems = no VTEC.
I've even seen a big dent in an oil pan mess with pressures and capacity and that caused the ECM to get bad readings from the oil system monitors and it wouldn't allow VTEC to engage.
Ultimately though, whatever the cause, the controller of it all, your ECM, is what ultimately determines, based on all the other system readings it receives from the various engine and electrical components, if VTEC is allowed to engage or not.
~ Josh
I have a crude cut and paste explanation of what VTEC is on my web site. You can read it and get some idea as to how VTEC works. Technical? A little bit, but you can easily understand it if you have basic knowledge of how an engine works.
http://home.mindspring.com/~redracer95/ ... /id21.html
Reasons that it will stop working range from CEL codes to faulty VSS-speedo readings, and/or a tachometer that isn't working correctly, low oil pressure or even oil that's old and thin...bad coolant temp sensor, faulty VTEC solenoid, VTEC pressure switch that's bad...the list goes on.....
The VTEC mechanism is operated via hydraulic pressure, hence why you see that I have listed so many of the problem sources as being oil related. VTEC is very much affected by oil/oil pressure related matters. At low speeds the oil flow is closed off from a valve via the VTEC solenoid pressure switch which allows the hydraulic pistons in the rocker arms to operate independently - no VTEC engagement. At high speeds (VTEC engaged) the pressure switch allows the oil into the passage which causes the hydraulic pistons to lock the primary, secondary and mid rocker arms together. Hydraulics being the key actuator of the mechanism, so oil is where the hydraulic pressure is derived. Oil problems = no VTEC.
I've even seen a big dent in an oil pan mess with pressures and capacity and that caused the ECM to get bad readings from the oil system monitors and it wouldn't allow VTEC to engage.
Ultimately though, whatever the cause, the controller of it all, your ECM, is what ultimately determines, based on all the other system readings it receives from the various engine and electrical components, if VTEC is allowed to engage or not.
~ Josh
I have a crude cut and paste explanation of what VTEC is on my web site. You can read it and get some idea as to how VTEC works. Technical? A little bit, but you can easily understand it if you have basic knowledge of how an engine works.
http://home.mindspring.com/~redracer95/ ... /id21.html