Here's a history of Nissan's innovations in VVT over the years. On Camshafts and Variable Valves Visualize a camshaft on a top of an engine, turning via the timing belt or chain from the engine's crankshaft.
TorqueNews Hot Topics. Nissan News, Reviews and Pricing. Subscribe to Torque News on YouTube. Comments Grham wrote on June 3, - am Permalink.
Bought a Nissan Qashqui last year and it has an intermittent habit of a brief interval of power fade. This is more noticeable on inclines when the accelerator is held in a constant position, with sufficient fuel supply for the situation. It will pick-up and continue as before? This can also occur on the level. Could this be a VVT issue? Aaron Turpen wrote on June 3, - pm Permalink. Most likely it's a fuel delivery or transmission issue.
Watch your tachometer. Does it waver? It's more likely to be either a confused CVT it happens or the aforementioned fuel issue. If it's the VVT, then it's because you're right at the RPM point where the ECU tells the cam gear to open, but normally you will not know it's happening at all and today's engines usually do so dynamically, so it's not sudden, but gradual.
Steve Waclo wrote on December 1, - am Permalink. Even though you may technically be able to continue driving with a bad VVT solenoid, the issue can cause damage to additional parts, such as the VVT actuator. So, you should address the issue as soon as possible. Hugh Hunkeler, Three decades of automotive engineering. How long can you drive with a bad solenoid?
It depends on the solenoid. When the VVT solenoid is malfunctioning, the entire system can be compromised, which may result in intake and exhaust valves opening and closing at the wrong time. This typically causes the fuel economy to drastically reduce. A faulty VVT switch will also cause the engine to misfire or appear to stumble when your vehicle is loaded with extra weight, climbing hills, or when you apply quick pressure to the throttle for instant acceleration.
This is caused commonly by an electrical issue with the switch and not always the switch itself. The variable valve timing solenoid is a component of the variable valve timing system that manages the oil flow depending on the engine speed and load. A VVT solenoid in good working condition improves performance and fuel efficiency. When it comes time to have your variable valve timing solenoid or solenoids replaced, your vehicle may have symptoms such as an illuminated Check Engine Light, loss of power, bad fuel economy, and a rough idle.
VVT variable valve timing is a general term for the system that keeps timing of the valves, and is typically designed to work with the camshaft. Depending on the make, model, and year of your vehicle, transmission solenoid replacement costs can vary. Then I put the alcohol soaked rag on the end of a screwdriver, stuff it into the solenoid base and twist. Remember, though, that this is only applicable to dirty sensors and not busted ones. Trademark erosion may not impact the environment, but marketers have noted the lexicographical slide of some brand names into generic labels.
When Honda started tinkering with VTEC in the early s, it sparked an internal-combustion revolution that spread to nearly every brand. The simplest of the resulting variable-timing systems employ cam phasers, or mechanisms that change the relationship between the crankshaft and the camshaft s. Phasers provide a range of adjustment, but only for valve timing.
VTEC, on the other hand, works in a stair-step fashion, shuttling between two or more distinct cam profiles to change three variables: valve timing, duration, and lift. Honda merged the worlds in , adding those relatively simple cam phasers to the already complex VTEC system.
Initiating a sort of controlled trademark erosion, Honda has evolved VTEC into a family of separate systems encompassing various combinations of a core set of technologies. Here is how they work:.
As revs climb, the computer directs oil flow A through the rocker shaft. That third rocker follows a different cam profile optimized for higher engine speeds.
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