VSV 'air leak' sound

[Jimnist]

It seems as though my Camry has a gremlin in it. I've noticed that sometimes for no apparent reason, the engine will run very rough and will hesitate severely when i start it up (both cold and warm). It usually happens once(a fornight at most) and is usually fixed if i shut off the engine for 5-10 secs and restart it.

There's also been an air leak/sucking sound coming from the electronic VSV that bolted to the top left corner of the firewall on my Aussie Camry, not sure if it's different for US. Could this be causing it? What does this elctronic VSV do? What do the two hoses that go into it control with vacuum? I never heard this sound until it started doing this funny start-up thing.

I'll try to get a pic if you don't know what i'm talking about.

Any help is appreciated.

[white90dx]

The VSV on the firewall is the A/C Idle-up VSV. It shouldn't be making any noise... When active, it applies vacuum to the larger vacuum modulator on the intake manifold which allows extra air into the engine while the A/C is on. You will probably want to fix it (try just capping the two vacuum ports on the manifold first to test), but this probably isn't the source of the hesitation.

How is the rest of the car doing? Fuel filter, ignition system, air filter, etc? Any check-engine lights?

-Charlie

[Jimnist]

Originally Posted by white90dx

The VSV on the firewall is the A/C Idle-up VSV. It shouldn't be making any noise... When active, it applies vacuum to the larger vacuum modulator on the intake manifold which allows extra air into the engine while the A/C is on. You will probably want to fix it (try just capping the two vacuum ports on the manifold first to test), but this probably isn't the source of the hesitation.

How is the rest of the car doing? Fuel filter, ignition system, air filter, etc? Any check-engine lights?

-Charlie

Rest of the car is fine. Fuel filter, oil and filter and air filter was changed 30th Jan this year. No check engine lights, i think when the rpm dropped down to about 500 the check engine would turn on, but turn back off as soon as it fluctuated back up again. This only happened once last last year, which was the first time i've ever seen it happen(both idle drop that low and the funny rough running and hesitation).

By ignition system, you mean the leads, plugs, cap and rotor and ignition module right? I think they're alright. Not sure when they were replaced as i got the car mid last year. Ignition module does not have the tell tale symptom of runny funny when it's very humid.

When i was changing the high pressure power steerig hose, i accidently plugged those small thin hoses in the other way around. I immediately noticed a difference, switched the engine off and swapped them back. Could that have an effect on it?