Greetings, and good evening.

I'm here to ask about this horrible rasping noise coming from my 1985 12A powered Rx-7. I have no clue from where it is emanating, and would appreciate any help that you can offer.

I've changed the air filter myself, and most of the more accessible parts have been replaced within the car's lifetime.

 

is it coming from under the hood, from the rear end, from the wheels, from the radio... does it sound like a freight-train, a leer jet, a mouse, a file on hardened steel...??? Give us a bit more help...

Jeff

 

Thanks for replying.

It's coming from the air filter's housing.

 

check your coasting valve

 

does it sound like a duck getting sucked into a shop vac in the middle of a tornado? If so, do a search for "Shutter Valve". if the shutter valve pulls at idle, it's bad... I don't have the pic showing which hole it is under the air filter top though... it's around here somewhere.

Jeff

 

That wouldn't be controlled bu one of those vacuum contolled solenoid valves next to the air filters housing. would it?

 

ummmm... not too familiar with the emissions control.... why? did you remove the rat's nest?

 

It's not quite that loud. It's more of an unpleasant asthmatic rasp. It's only audible at idle.

 

nevermind, I just saw your other post....

do you have a/c or cruise? if not, remove the whole rat's nest, plug off all the holes, and call it a day... oh, and remove the air pump, acv, and make a bloack off plate for the acv... if you don't know what I'm talking about, sorry, I'm just assuming you know a bit about rotarys. Do some searches on what I just said (acv, air pump removal, and rat's nest) and you'll learn a lot. If you live in a smog-controlled state (i don't know anything about emissions) then ignore everything I just said.

I would say check your shutter valve... it makes weird noises at idle if it's bad, and it sucks air through if it's bad.

Jeff

 

No... I assume the rat's nest is that tangle of tubes and wires next to the air filter. Part of the plastic housing on that things body broke off. Now one of the hoses isn't connected.

 

oh, is your car carbed, or fuel-injected? if it's a carb, are you sure it's not just normal venturi effect sound (sounds like a little sucking sound, like when you suck on a straw at eh end of a glas)

Jeff

 

goes up the back side of the air cleaner by the idle compensator. yes it does come from the rats nest at least the vacuum for the shutter valve does. tried to block the vacuum before the shutter valve and it ran like crap. So ended up pluging the hose that went to the air cleaner. Been fine ever since.

 

I'm sort of ignorant about my cars engine, that's why I'm here. I'll do those searches, thanks for your help.

 

It's carb, but it's not normal air intake noise.

 

With the car running take the top off your air cleaner and see if the large hose that goes up to it in the rear is sucking air. If it is plug it.