I'm not quite sure where to start with this, but i'm not sure this is normal. I have a 93 5spd. ex coupe, and whenever I push the gas to accellerate, I hear a kind of hissing noise. It gets louder the farther I push the gas pedal in... if i just lightly push it I don't hear it. It only does it while it's in gear though. Could this be a gas leak or something? I don't smell anything, but I can hear it. I'm not quite sure what to think. Is there somewhere i could easily look to see if it is in fact a gas leak? I took it in for required maintenance about a month ago and the mechanic didn't say anything about it... maybe he didn't notice it. I'm not sure what to think about this... any advice would be welcome...

 

vaccuum leak?

if its a fuel leak do you see any fuel?

 

Do you have an air intake?

 

I can't see any fuel on the ground or leakage anywhere under the hood... and I don't have an aftermarket intake. I didn't think of a vacuum leak, but that sounds like it could be. How could I check and see if that is the problem? Would a vacuum leak cause the car to not accellerate as quickly, and maybe have lower gas mileage as well? I've been noticing that, but of course that could be unrelated... I'm just not sure.

edit:

Also... sometimes the idle goes up and down while in neutral, like, it goes down to just barely before it could stall, then goes up to around 1000, and keeps fluctuating for a while. Could that also be related to a vacuum leak?

 

You made no mention of power loss at speed, but the symptoms you discribe could indicate a blocked/clogged catalytic converter.
The conditions caused are usually:
1) loss of power at higher rpm, getting worst as the condition continues
2) Hissing noises from a blown exhaust donut/gasket as exhaust gas pressures increase (as rpm's build) between the engine / converter
3) Deminishing gas milage as the engine works harder to develope power.

Vacume leaks (on the intake side (where else)) woud actually be maximized at idle and decrease as you opened the throttle. Just the opposite of what you discribe.


Modified by P_Adams at 5:48 AM 6/26/2005