[Chance]

When I decelerate from anything more than about 1,500rpm, I get a moderately loud clicking sound emanating from the engine compartment. One of my friends said it was just the Anti Backfire Valve, and that it was normal.

Well, I never heard it before. So something must have changed, and all is not well in my rotary world.

Could it actually be my ABV? If it is, does this mean there is something wrong with it? Anything dangerous to my engine?

Now would be good as any time to mention that I have what is believed to be a clogged catalytic converter, which is causing on and off power loss in all rpm ranges. Could this condition have affected my ABV because of the sudden and immense back pressure? Or could it be a non-harmful side affect? I presume an ABV works by injecting oxygen, helping to burn off unused fuel... Maybe?

Anyway, not the point. I have no idea what is wrong with my car... And I don't have the money to take my car to a mechanic and have him/her run a diagnostic. Not unless I have to.

I leave it in your grease covered hands.

Thanks

[Chance]

Anyone heard of this?

74RX4

iTrader: (10)

Have not heard of this, but the #1 anti-afterburn valve has an electrical plug. Here's a picture. http://intertron.com/ron/images/carb/c10.jpg Try unplugging it and see if the clicking stops.

I think its more likely to be the shutter valve. http://intertron.com/ron/images/carb/c13.jpg
There is a hose going from the shutter valve up to the air cleaner. Disconnect it from the bottom of the air cleaner and plug the end of the hose.

DivinDriver

iTrader: (15)

Is it a repetitive clicking that continues during deceleration, or just a single click when deceleration starts?

aussiesmg

iTrader: (1)

I concur with the shutter valve description, do a search on this. It's easy to block it off and has minimal impact on economy or driveability

[Chance]

It's a continuous clicking until the RPM's drop below 1,500 or so.

'74 & Aussie, I check that out. I'll post the results tomorrow when it's daylight. Hopefully either one of those fixes works.

By the by, just so everyone knows, as I neglected to write earlier... I have a 1984 Mazda RX7, 1.1LTR 12a with a 4 barrel stock nikki carb.