My recently acquire 2002 has intermittent leaking/hissing periods when the engine is engaged. I have the sound of air leaking or being moved. I hear the individual stokes of the engine, I dont feel any missing in power, No light comes on. After around 60 to 90 seconds of driving, quicker if I press the accelerator the sound has gone away. I wonder what I can do to check this out, I have not been able to pinpoint the area it comes from other than the engine area. thank you for any idea where to start
Pretty sure this is just one of the many weird sounds the car makes. Someone else correct me if I am wrong.
It's not a sound my 2002 makes. Can you open the hood and poke around with the engine running to source the noise?
My car makes all sorts of strange noises, both while it is running, and after I've shut it off. I've never stopped to investigate, because I've always assumed they are noises my strange but awesome hybrid car makes. There is specifically a weird sort of hissing sound my car makes sometimes while I'm driving, but it's random, and it only makes it for a second or two and then stops. It almost always makes the same noise after I've shut the car off. It's not something I can make happen, and I've never been quite sure why it makes the sound, but my car has never had any problems in the 6 years I've had it (and it's made that same noise all those years), and my car has been serviced every 5,000 miles since I bought the car, with no reports of anything wrong, so I'm going to assume there is nothing wrong with the car.
I suggest that you have the exhaust system checked, in particular the HCAC (hydrocarbon absorption chamber) which is near the catalytic converter. There is a valve which routes the flow of exhaust gases to the HCAC and perhaps there is an exhaust gas leak causing the sound that you reported. The HCAC is a system which is unique to Classic Prius; fortunately later generations do not benefit from that particular design.
