[formula97]

I drove my 97 Formula today and it seemed normal for the first 10 minutes. Then I started hearing a strange noise from the rear when idling (almost sounded like speaker feedback when you place the microphone too close to the speaker).

I shut down the car, waited a minute, then when I turned the key (no start), the fuel pump sounded horrible when it was priming!

The car starts and still drives fine, what should I expect if I ignore these sounds? Seems like it was on and off today, more noticeable at lower speeds. First time experiencing these noises.


The fuel pump was replaced just a year ago, and I don't think I put more than 3000 miles since that time.

Any ideas? It was quite hot and humid today, and I don't usually drive the car much.

Thanks!


Also like to add -- I opened the fuel cap and it was venting for a while. I closed it, waited 10 seconds, then opened again and it was continue to "vent".

After waiting an hour, I turn the key and pump prime sounded normal. Also started up and revved normal too.

Could it be the EVAP? I also noticed a pretty strong odor when I stopped the car but left it running for a minute.

 

[steveo]

important to note if the tank was under vacuum or pressure

if it's under pressure, that wouldn't hurt the pump any, would it? if anything it would help the pump (until your tank explodes or something)... the evap canister and purge system is only to relieve pressure

there's a seperate tank air inlet valve. if you have serious amounts of vacuum in the tank, it could be clogged.. or something..

 

[formula97]

important to note if the tank was under vacuum or pressure

if it's under pressure, that wouldn't hurt the pump any, would it? if anything it would help the pump (until your tank explodes or something)... the evap canister and purge system is only to relieve pressure

there's a seperate tank air inlet valve. if you have serious amounts of vacuum in the tank, it could be clogged.. or something..

Thanks, not sure what you mean by "vacuum or pressure".

When I unscrewed the gas cap, the tank vented. I then closed the cap, waited 30 seconds, and it vented again.

I just hope my car does not explode! BTW, no SES light yet...

 

[formula97]

Would it help if I said the fuel pump sounded "faster" before making that strange noise? Would that mean the tank was under pressure rather than "vacuum"?

There was a pretty big difference between my garage and the outside temps at the time, wondering if that helped build too much pressure in the tank.

 

[formula97]

Is it possible the sounds I heard were not coming from the fuel pump? I tried to replicate the issue today and could not. And I smelled nowhere near as much gas today as I did yesterday.

I still may have the dealer check out the EVAP system to make sure everything's OK. What else should I be looking for?

 

[Racy Roadmaster]

With mechanical things,usually but not always ,its a cry for help!
I would really try and listen to the noise again ,if it presents itself,and deterrmine exactly when it happens. If it haappens again,leave it running and remove the gas cap,see if the noise changes at all. I really dont think
your car is going to blow up,so get that out of your head! ed

 

[formula97]

Been using the car a few times this weekend (just came back from a 30 minute drive as well).

Can't seem to duplicate what happened the other day. Still runs great, and still no SES light. But I was able to smell some gas just now. Pretty sure I would hear a "whoosh" if I unscrew the gas cap.

I know it is hard to diagnose over a comment on the message boards, but any idea what I could be up against?

 

[Racy Roadmaster]

THIS MAY BE TO SIMPLE AN ANSWER,How about the fuel cap,have you tried to swap it with a "good" one? ed

 

[formula97]

THIS MAY BE TO SIMPLE AN ANSWER,How about the fuel cap,have you tried to swap it with a "good" one? ed

LOL......wish it WAS this simple!

Cap is about 4 years old, and my car passed inspection less than 2 months ago.

 

[Racy Roadmaster]

Thats not a very sciencitific approach,the fuel cap may have corroded or clogged between the time it got inspected and the time your pump started to make noise. Just sayin. ed

 

[formula97]

Thats not a very sciencitific approach,the fuel cap may have corroded or clogged between the time it got inspected and the time your pump started to make noise. Just sayin. ed

The fuel cap is completely plastic and not vented, so I am not sure what would corrode. The seal looks intact, and I assume if the cap was not sealing properly that I would not hear that "whoosh" when I unscrew the cap.

I'm gonna have the dealer look at it tomorrow, hoping to get it straightened out before next weekend.

 

[steveo]

yeah lt1 caps have no pressure blowoff, they're supposed to seal completely.

 

[formula97]

Dealer called and said everything checked out with the EVAP system. No signs of leaks, etc.

He did say it could be the fuel cap.