car acts like it's out of gas with 1/4 tank

Reply

  #1  
Old 07-27-05, 10:20 AM
repbuddy
Visiting Guest
Posts: n/a
Cool car acts like it's out of gas with 1/4 tank

My 93 bonneville oftens stalls when coming to a stop and also when going up a ramp while turning right. This usally happens when I have about a 1/4 tank of gas. I know I'm not running out because I can start it back up and drive it for as many as 50 miles. Once the symptom begins it will continue untill I fill up then it runs like a champ. Had it in the shop a couple of years ago thinking maybe something was in the tank or possibly the fuel pump was going bad. They took the tank off and found absolutely nothing. The mechanic suggested that I was running out of gas but also told me that the tank still had over 5 gallons left in it. I'm clueless, anybody out there got any ideas? I used to get 360 or more miles out of a tank, now I get about 270 before this starts happening.
 
Sponsored Links
  #2  
Old 07-27-05, 02:44 PM
Lugnut's Avatar
Member
Join Date: Jan 2001
Location: Kansas City, Missouri.
Posts: 1,172
Just a theory. The fuel pump is cooled by the liquid gasoline. When the tank level drops, the pump runs hotter which magnifies a problem with a motor or connection.

Not much personal evidence to back up my theory but I have always believed that is the real reason manufactures recommend keeping the tank 1/4 full.
 
  #3  
Old 07-28-05, 03:01 AM
Member
Join Date: Dec 2001
Posts: 2,538
if the baffle in the tank is loose or broken it could cause this problem if the baffle is ok you should probably go ahead and change out the pump and strainer and pump to fuel sender hose.
 
  #4  
Old 07-29-05, 05:49 AM
repbuddy
Visiting Guest
Posts: n/a
Cool reply

I don't think the fuel pump is failing due to a lack of fuel by getting hot because if the car has had a day for everything to cool down and I start it up with 1/4 tank or less the symptoms occur the first time I come to a stop, also the harder and faster the stop the worse the syptoms are. I'm wondering if it has to do with some type of vacume problem. The baffle was fine according to the mechanic and there was no trash in the tank. He also tested the fuel pump and said it was fine. Maybe there is a ghost in the tank and it comes to life at a 1/4 tank. Thanks for the ideas though, keep'um coming. I am willing to entertain any ideas at this point.
 
  #5  
Old 07-29-05, 09:26 AM
Member
Join Date: Dec 2001
Location: nc
Posts: 616
Just guessing..

Bad gas cap? Do you hear a release of pressure when you remove it?
 
  #6  
Old 07-29-05, 09:32 AM
Member
Join Date: Aug 2003
Location: Cape Cod
Posts: 4,320
Originally Posted by repbuddy
Had it in the shop a couple of years ago ...
If it's still bugging you maybe it's time to go back
But try a different place, you need a second opinion
Basically your engine is acting like it's starving for gas when the level is below 1/4 tank on your gauge and you stop,(the gas is sloshing away from the pump), or you are turning (the gas sloshing away from the pump)
The symptoms continue until you fill up
It does lead me to suspect the pump is overheating
The mechanic would have to overheat the pump to check it properly
Regardless, the fact that you have had this happen numerous times over the past few years leads me to think that now the pump is suspect anyway
They are liquid cooled and running them w/less than a 1/4 tank is bad for the pump
Now, with your situation (simplified), 1/4 tank is like E, and 1/2 tank is like a 1/4 tank
So driving with less than 1/2 tank is bad for your pump
It just really doesn't look good for that pump
 
  #7  
Old 07-29-05, 10:34 AM
repbuddy
Visiting Guest
Posts: n/a
reply

I don't believe it's from over heating because it quits at the end of the driveway just after startup(see above). I did replace the gas cap last year just out of curiosity. Now that you mention it I don't remember hearing a pressure release when taking the cap off. If the cap is good what else could cause this?
 
  #8  
Old 07-31-05, 02:51 AM
shelby11
Visiting Guest
Posts: n/a
Cheap Solution

Just an Idea, Keep the level over 1/4. Problem solved!
 
  #9  
Old 08-01-05, 10:35 AM
repbuddy
Visiting Guest
Posts: n/a
reply

I'm interested in fixing the problem not passifying it!
 
  #10  
Old 08-01-05, 10:49 AM
Member
Join Date: Dec 2001
Posts: 2,538
really there is only a few possibilities either the sending unit is reading incorrectly and you are running the tank so low you are running out of gas.
fuel is sloshing around and its running out of gas due to a broken or loose baffle.
or the pump is going bad.
 
  #11  
Old 08-02-05, 10:29 AM
repbuddy
Visiting Guest
Posts: n/a
reply

Sending unit was replaced 2 years ago. Symptoms begin occurring with about 5 to 8 gallons left in the tank. How do I know? the mechanic said it had at least 5 gallons in it when he pulled the tank. Thanks anyway though. Someone suggested that maybe it was a fuel pressure regulator problem or maybe a vent problem with the tank. Anybody else out there with any thoughts? Any ideas are welcomed and I do mean any.
 
  #12  
Old 08-02-05, 01:12 PM
Member
Join Date: Dec 2001
Posts: 2,538
you have recieved alot of help from people in this thread already if you do not wish to get a second opinion at another shop or keep the level at above 1/4 and just live with the problem then there is not much that can be done.
if you wish to replace parts unrelated to your problem such as regulator by all means go ahead and do so just dont be to dissapointed when the problem still occurs.
 
  #13  
Old 08-05-05, 10:41 AM
repbuddy
Visiting Guest
Posts: n/a
Thumbs down reply

Oh I'm sorry, I thought this was doityourself.com not take it to a shop .com All of the things reccomended I have already done. Anybody else out there got any ideas. Anything other than reccomending that I take it to the shop is welcome. Let me just reittterate I know it's not the sending unit, It's not the fuel pump, the fuel pump's not overheating, it's not the baffle. For you mechanics out there, could it possibly be a pressure regulator or maybe a tank vent problem. The symptoms can occur with as many as 7 gallons left in the tank. I know what all of you are thinking and yes your right I am stubborn!
 
  #14  
Old 08-06-05, 07:14 AM
ggamble
Visiting Guest
Posts: n/a
I have a 92 Bonneville, that has always done the same thing, now it is doing it, when it is full of gas, but not all the time, just when the temp. gets a little over 200 in these hot days, guess I will keep it for a winter time car, all the shops I taken it to, tells me nothing is wrong with it, run good then.
 
  #15  
Old 08-06-05, 06:42 PM
jeffstevens
Visiting Guest
Posts: n/a
You were saying is stalls when you turn right, what about left? It sounds like a problem with the pickup. Pull the pump, and have a look. You may need to buy new straps for the tank. Also the pump may be the wrong length.
Originally Posted by ggamble
I have a 92 Bonneville, that has always done the same thing, now it is doing it, when it is full of gas, but not all the time, just when the temp. gets a little over 200 in these hot days, guess I will keep it for a winter time car, all the shops I taken it to, tells me nothing is wrong with it, run good then.
 
  #16  
Old 08-08-06, 07:27 AM
Member
Join Date: Aug 2006
Posts: 1
My turn...

OK, I also have this problem - exactly. It started out with the 1/4 tank of gas stalling and progressed to stalling (just recently) regardless of how much gas I had, including while I was driving down the highway to an ending stall lastnight on a country road to never start again. I just had it towed home. How on earth am I supposed to fix this car???
 
  #17  
Old 08-08-06, 12:27 PM
Pendragon's Avatar
Member
Join Date: Jul 2002
Location: USA
Posts: 1,839
Fuel pump relay.

A lot of GM/Pontiacs have a dual relay system, here's how it works...

In the sender for the oil light/gauge, there are TWO relays. One for the light, one for the fuel pump. If the standalone relay quits, then the one in the oil sender works. If the one in the oil sender quits, the engine quits.

What I suspect is happening has nothing to do with your fuel level at all, but rather your oil level. Coming to a hard stop or taking a hard turn in one direction (but not the other), starves the oil pump for just a moment that it loses enough pressure to switch the relay off. At that point, oil level returns and you can start the car right back up.

The relay is a cheap part to replace. If you can find it.
If the fuel pump and a/c relays are the same on your car (and they probably are), you can swap them around as a test (assuming the a/c works ok).
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes