jason_home

Hi All,

I'm a newbie coming for help. Thanks!

My car is 93 accord 4dr EX automatic, with 220000km on it.

The gas tank is leaking and my mechanic suggested filling only half tank every time. It works - No more leak from the tank.

However, I found the engine was cut off easily at any stops, no check engine light on. When I press the brake paddle, I could see the idle speed went very low and died sometimes - not if I approach the stop slowly. This happened only when my gas in tank was low to about 1/4 or less. Once I re-filled the tank to half full (couldn't be more because of the leaking), everything was fine: the engine was powerful, and idled smoothly at arround 700+.

I guess the engine was cut off due to low fuel pressure at idle, but I don't know how it related to a leaking tank.

My questions are:
1. Could the problem be solved if I fix the leaking tank?
2. Is it possible that my fuel pump is too old and needs to dip deeper in gas to keel cool?
3. Could it be malfunction of a pressure sensor? (fuel tank pressure sensor?)

Here is a list of what have been done to the car recently, after the problem happened:
a. replaced fuel filter (new)
b. replaced fuel pressure regulator (used)
c. replaced IACV (used, cleaned)
d. replaced PCV (new)
e. cleaned FITV
f. cleaned butter fly (from outside, not the whole throttle body)
g. re-soldered all solder joints on main relay
h. cleaned EGR valve
i. cleaned EGR ports (cleaned 4 only)

I've ordered a front engine mount (I thought it could be a high torque from my broken engine mount caused engine overload at idle), and I'm planning to remove and clean the throttle body (to improve idle). However, I do feel it's a fuel tank related issue.

It can't be the transmission. Engine stalls at neutral as well. It can't be a leaking brake booster - because everything is OK when fuel tank is half full.

I appreciate any of your response!

Thanks!
Jason


Modified by jason_home at 9:12 AM 6/8/2008


Modified by jason_home at 10:47 AM 6/8/2008


Modified by jason_home at 10:48 AM 6/8/2008

The_Caged_Bird

On fuel injected cars the fuel system MUST reach the appropriate pressure, thus the reason why when you get to the gas station and you loosen the filler cap you hear that hissing. You don't hear that hissing though because you have a leaky tank.

You don't hear that hiss all the time with carbureted cars the reason why is because they never get above 7 psi of fuel pressure.

I'm almost certain that if you replace the tank your problems will go away.

You should replace the tank anyway, it's a safety issue, not just for you but for everyone else. It's just something about leaking combustible materials and hot exhaust pipes that don't really mix well...

jason_home

Thanks for your response, Caged_Bird!

I'm not clear how fuel system pressure and fuel tank pressure related. Through a sensor? Fuel injection system need a pressure (fuel SYSTEM pressure) created by a fuel pump. Why do we need to maintain pressure in the fuel tank (fuel TANK pressure)?

I saw a post with similar issue as mine but a GOOD tank, and the issue was resolved by replacing the fuel pump. The owner got easy engine stalls with 1/4 or less gas in tank at very beginging, and then changed to 1/2, and finally had to keep more than 3/4 tank of gas before getting a new pump.

I do plan to replace my gas tank, but am trying to do it together with a new pump, if it is defective. There would be no fun to drop the tank twice in a week.

on the other hand, I got problem finding a new tank. I see it on http://www.autopartswarehouse.com at $186 with free shipping - but they don't ship it to Canada! All canadian webs I know don't hold the tank.

Any suggestion will be welcome!

Thanks!
Jason

The_Caged_Bird

Oh wow, I completely missed that you HAVEN'T replaced the fuel pump.

Yeah, it's probably the pump, I'd go ahead and replace it when I replaced the tank.

I'm not 100% on fuel injection and line pressures, the pressure in the tank and why it's needed is an enigma to me as well. I just know that when you remove the gas cap (or have a leak) it will cause the car to not run correctly. I'm guessing that it has something to do with the fuel return line to the tank from the fuel rail which, I'm guessing, is lightly pressurized.

The way I figure, it's such a bitch to replace the fuel pump, might as well replace it with a known good one while you have the chance. Of course I'm of the belief that if you buy a good part now, and take care of all questionable ones that might break in the future you'll have a good, reliable, car. That's how I built my 'vette, it will be thirty-one next week, and up until two weeks ago it was my daily driver for three years.

jason_home

Thank you Caged_bird!

I wish I can keep my car beyond its 30th birthday as you did.

Please refer to this thread:
http://jeephorizons.com/phpbb/...12989

I got very similar issue as that jeep owner who has replaced his fuel pump, and his tank did not leak.

Replacing fuel tank and pump will cost more than $500. Just want to be sure.

Any more ideas?

Thanks!
Jason

jason_home

Could the fuel level sensor in tank cause this problem?

Appreciate your comment!
Jason