Is it normal for my max to loose pressure in the fuel system after sitting overnight? It seems to run fine. Removing the gas cap after running gives me a good PSSSSSST sound but in the morning I get nothing. Will this hurt anything?

A few months ago I removed one end of the filer hose to drain the tank after some bad gas. I just replaced the hose wire clamp with a better one but it made no difference. Also recently I replaced a few fuel injectors. I see no evidence of excess gas being dumped in the engine – the plugs look clean and the car runs great!

My smell test seems to point to the fuel pump area. Any other suggestions? The fuel pressure must be leaking somewhere.

Thanks
Vince

 

Yes, the fuel pressure will dissipate. That's totally normal.

Also, the hiss you hear when you open the gas cap is the vacuum inside the tank, not positive pressure. The tank is kept at negative pressure so unburned hydrocarbons (gasoline vapor) can't escape.

 

mine never hisses when I go to the gas station to fill up and I remove my gas cap, no matter how much I have in my tank at the time....

 

hmm...my fuel system releases pressure every time i open the cap after a drive, even a short one.

 

so do I have something wrong with my fuel system?

 

michael:
Try a new gas cap - 5 bucks. I would expect some residual vacuum when you take the cap off after a drive - happens to me every time I go to get gas - even if its a 2-min drive from a cold start.

OP:
the pressure/vacuum will dissipate overnight as already stated.

 

would that cause any issues with driveability, power, mileage? is there any reason to replace the gas cap if it's bad?

 

I don't know if it will cause any of the problems you mention - but there is a reason the gas cap is supposed to maintain a seal - so why try to outsmart that? why not just replace it.

 

i have the hiss on my car when i open the gas cap, but my mom's tercel, my dads caravan, and my friends camry doesnt do it. is it something only found in maximas?

 

Nope.. happens on both my cars today (one is not a maxima) and has happened on every other car I have owned.