Car runs like doo-doo under 1/2 tank of gas...
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Car runs like doo-doo under 1/2 tank of gas...
MY 95 runs like garbage under a half tank of gas. After I take a right turn, or am in one (like an exit or onramp), if I give her over 1/2 throttle she'* cuttin' out and chugging hard. Gets really bad as I approach near empty (5-7 gallons left or so). The problem then starts to appear even in a straight line when the tank is low. Only this time, the power is cut back like it'* running on 5 cylinders if you go anywhere'* near WOT. IT won't completely cut out then, but just no power. It'* only rights turns and at least 1/2 throttle where she cuts out and chugs.
So with all that said, what it happening here? I thought that bad fuel tank design with the bad baffles was only in '92s? At 110k miles, I have not changed my Fuel filter since I've had this car from 87k. This problem just appeared back in Dec., and has progressively gotten worse up to now. Maybe the Fuel filter is the cause, dunno. Pump sounds normal when it primes. Not loud when priming or noticeable when running the engine. Haven't checked fuel pressure yet (can't find my gauge - plus it'* been like the Arctic here lately) and will probably check the regulator today to see if it'* working properly.
And to top it all off, car has been surging and rolling at idle lately when she'* warmed up. She stumbles down to around 600 rpm, in gear, and then the IAC finally kicks it back up. I think my MAF and TB are dirty, but am also wondering if my O2'* are starting to go. Gotta get her on the scantool to check this one out I think. But the rolling idle and bad fuel delivery might possibly lead me to a leaking or erratic regulator? Dunno. Any ideas before I get brave and go out in the cold to start deciphering this set of problems?
TIA.
So with all that said, what it happening here? I thought that bad fuel tank design with the bad baffles was only in '92s? At 110k miles, I have not changed my Fuel filter since I've had this car from 87k. This problem just appeared back in Dec., and has progressively gotten worse up to now. Maybe the Fuel filter is the cause, dunno. Pump sounds normal when it primes. Not loud when priming or noticeable when running the engine. Haven't checked fuel pressure yet (can't find my gauge - plus it'* been like the Arctic here lately) and will probably check the regulator today to see if it'* working properly.
And to top it all off, car has been surging and rolling at idle lately when she'* warmed up. She stumbles down to around 600 rpm, in gear, and then the IAC finally kicks it back up. I think my MAF and TB are dirty, but am also wondering if my O2'* are starting to go. Gotta get her on the scantool to check this one out I think. But the rolling idle and bad fuel delivery might possibly lead me to a leaking or erratic regulator? Dunno. Any ideas before I get brave and go out in the cold to start deciphering this set of problems?
TIA.
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Re: Car runs like doo-doo under 1/2 tank of gas...
Originally Posted by DJ SHO
At 110k miles, I have not changed my Fuel filter since I've had this car from 87k. This problem just appeared back in Dec., and has progressively gotten worse up to now. Maybe the Fuel filter is the cause,
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ok
hmmm.. if it only happens at lower than a half a tank...wouldn't the filter make it happen all the time? My geuss it'* prolly like what happend to my buddy and his 9C1, his fuel pump just couldn't work anymore.. it was having to do more work that it couldnt handle once it ran down to half a tank.. its kind of a wierd thing though.. ya try to check the pressure on that.. cause especiallly if it gets bad past half or more throttle.. sounds like the FP cant keep up.. but that'* just my.02 cents worth
good luck
good luck
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Its possible that the fuel strainer fell off, but if that'* the case then i don't think you would notice a difference between part throttle and WOT.
#5
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Fuel pump. As the fuel is the coolant for the pump, it gets progressively hotter as the amount of fuel decreases, and loses efficiency.
Change the fuel filter, anyway.
Change the fuel filter, anyway.
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The gas issue sounds like a clogged strainer. To fix: Replace pump and strainer. You'll hit yourself if you try to go cheap and just replace the strainer, only to have the pump fail later on. Also, if you haven't personally done a fuel filter in almost 30K miles, I would do one at the same time as you do the fuel pump. Every GM pump that I've seen fail has a dirty or plugged fuel filter. Anybody who has a GM fullsize truck will know what I'm talking about.
For the idle, I would clean the throttle body. Specifically the back side of the throttle plate. Either do it on the car, or pull the whole thing off and make 'er shine. DEFIENTLY pull the IAC and clean the buildup off it. Maybe do that first, it'* not hard to do and may be the cause of your problems.
For the idle, I would clean the throttle body. Specifically the back side of the throttle plate. Either do it on the car, or pull the whole thing off and make 'er shine. DEFIENTLY pull the IAC and clean the buildup off it. Maybe do that first, it'* not hard to do and may be the cause of your problems.