Whenever I accelarate, I hear a faint "ssssssssss" noise coming from under the hood. I never heard anything like that before! And this only happens when I accelarate, so if I take my foot off the gas pedal, I don't hear it.

It's making me think that it's coming from the fuel system, but I don't know.

I just did a TB + WP job and got all the belts replaced. I thought that was the issue, but that didn't solve it.

Thanks.

98 Accord Auto 4cylind

 

I would check vacum lines.

 

Or from/to where they connect to in order for me to trace them.

Thanks.

 

their should be a vacuum diagram under the hood on a sticker. or somewhere under the hood. i have a 92 its got a diagram there. could be the belts need to be adjusted, that or a belt driven part could be going out like the water pump or alternator. something with a bearing in it. u mention the water pump is new so that can be checked off the list. a belt tensioner can be noisy.

 

Thanks. I'll check those out.

 

Don't get your hopes up. Vacuum leaks are most noisy when idling. When you're accelerating, the vacuum isn't nearly as strong.

But... Look for a bad check valve on the big vacuum hose for the brake booster.

 

I checked the lines, and they look OK.

I noticed the noise doesn't come when the car is in Park, but as soon as I engage the gear, it comes up.

I tried listening to it, and it's coming somewhere near the firewall. I just can't figure out where.


If the noise gets louder, I will have to do something about it.

 

Have a friend start & stop the car while you listen under the hood; maybe that way you can narrow down the location better.

The brake booster would sound like it's coming from the firewall.