Bad running 89
Burning Brakes
Joined: Oct 2009
Posts: 773
Likes: 2
From: Minneapolis MN
Ohming the injector is 1 test & there are other test as well.I've seen injectors ohm correctly but still be bad.Before you did tune-up did engine have this problem?I've seen new spark plugs & new spark plug wires causing a misfire right out of the box.If ran fine before,put old spark plug wires back on & see what happens.Do you/your car have a MAF sensor?Check for vacuum leaks-use carb spray with a garden hose or fire exstisher close.I've never had a car catch on fire when spraying carb spray while checking for a vacuum leak.Just don't soak the engine with it & keep it away from the exhaust as much as possible.Also if you have a pointer digital thermometer,point it at each exhaust manifold cylinder & see if there is a temp. difference at each cylinder.Also you can dissconnect each fuel injector while car is idling & see if there is any change in rpm(assuming engine idles poorly).Pull the spark plugs,look at each carefully & see if there is carbon tracking on porcelin & see if each looks the same or if any are wet(fuel).Check for codes.Also hook up a vacuum pump to EGR & apply vacuum to EGR valve while car is running & car should die or almost die while applying vacuum.Keep us posted
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
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Can you think of one logical reason why running out of gas burns up the pump?
Because electric fuel pumps use gas tank vapor to cool their impellers. Remember, anytime air is compressed, it heats up. Think bicycle pump cylinder.
If there are no cooling vapors being supplied to the pump and the impeller keeps building up heat, the fuel pump can be permanently damaged. And in short order as many have discovered.
Because electric fuel pumps use gas tank vapor to cool their impellers. Remember, anytime air is compressed, it heats up. Think bicycle pump cylinder.
If there are no cooling vapors being supplied to the pump and the impeller keeps building up heat, the fuel pump can be permanently damaged. And in short order as many have discovered.
Team Owner
Joined: Jul 2004
Posts: 28,463
Likes: 3,288
From: Hartford WI
I have always run from tank to tank. many times I pull into a gas station and the car is stumbling just from a corner turn. I have yet to replace a pump under those conditions. My Walbro pump was installed because I needed more fuel. Also, the times I run out of fuel (a few), the pump stopped working but worked again once fuel was poured into the tank.
Again, the theory is nice especially with the in tank pumps and IIRC, Carter also claims that you should not run the pump dry but I am kinda skeptical because the engine does shut off with a lack of fuel and thus the pump
Team Owner
Joined: Jul 2004
Posts: 28,463
Likes: 3,288
From: Hartford WI
Thread Starter
Le Mans Master
Joined: Dec 2006
Posts: 5,154
Likes: 2
From: Ft Myers Florida
Ok thanks for all the help thus far, I have had to switch priorities to another car for a few days, now I'm back on this one.
Looks like I may have water in the tank after all. When it ran out of gas the fuel guage was still showing 2-3 bars ( I figured it was just the typical innacuracies), so maybe it has water at the bottom.
I took a about of pint of fuel out of it and although it does not look as obvious as the last bad fuel I pulled from another car, ther is a little sliver of miscolored liquid at the bottom. I'll be draining her tomorrow.
Also I poke a screw driver through the drainhole and could feel some crustiness in there.
Looks like I may have water in the tank after all. When it ran out of gas the fuel guage was still showing 2-3 bars ( I figured it was just the typical innacuracies), so maybe it has water at the bottom.
I took a about of pint of fuel out of it and although it does not look as obvious as the last bad fuel I pulled from another car, ther is a little sliver of miscolored liquid at the bottom. I'll be draining her tomorrow.
Also I poke a screw driver through the drainhole and could feel some crustiness in there.
Team Owner
Joined: Jul 2004
Posts: 28,463
Likes: 3,288
From: Hartford WI
Looks like I may have water in the tank after all. When it ran out of gas the fuel guage was still showing 2-3 bars ( I figured it was just the typical innacuracies), so maybe it has water at the bottom.
Also I poke a screw driver through the drainhole and could feel some crustiness in there.
Also I poke a screw driver through the drainhole and could feel some crustiness in there.
The drainhole on the outside?
Burning Brakes
Joined: Oct 2009
Posts: 773
Likes: 2
From: Minneapolis MN
Fuel keeps the pump cool not the vapor.Learned in tech school about this.Running low on fuel will cause pump to get warm/hot & its not meant to pump air.Also running low on fuel causes you to suck up all the stuff thats normally at the bottom of the tank unless the debris that floats on top of the gas in the gas tank gets low & can clog the fuel sock.Never a good idea to run out of gas & doing so can & will shorten the fuel pump life.
Team Owner
Joined: Jul 2004
Posts: 28,463
Likes: 3,288
From: Hartford WI
Fuel keeps the pump cool not the vapor.Learned in tech school about this.Running low on fuel will cause pump to get warm/hot & its not meant to pump air.Also running low on fuel causes you to suck up all the stuff thats normally at the bottom of the tank unless the debris that floats on top of the gas in the gas tank gets low & can clog the fuel sock.Never a good idea to run out of gas & doing so can & will shorten the fuel pump life.
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Thread Starter
Le Mans Master
Joined: Dec 2006
Posts: 5,154
Likes: 2
From: Ft Myers Florida
Bad gas Again! as I was pumping it out it was opaque. Opened up the tank and she was empty with the guage showing 3 bars, put it back together and added four gallons of fresh 93, after some sputtering and spitting out water she settled into a smooth idle and runs good now.
This is the second car I've found bad gas in, the other was so bad the car would not start period and the gas sample was two tone. I pooured some of the new gas into the glass just to see the dif and it was nice and clear.
I still had gas left over from that last car, what to do with it?
I just put about 5 gallons into my Mother in laws car, sorry I mean my wifes mothers car.
This is the second car I've found bad gas in, the other was so bad the car would not start period and the gas sample was two tone. I pooured some of the new gas into the glass just to see the dif and it was nice and clear.
I still had gas left over from that last car, what to do with it?
I just put about 5 gallons into my Mother in laws car, sorry I mean my wifes mothers car.
Team Owner
Joined: Jul 2004
Posts: 28,463
Likes: 3,288
From: Hartford WI
Mother In Law. MIL.
Malfunction Indicator Light, aka Check Engine Light. MIL
Coincidence? I think not
Thread Starter
Le Mans Master
Joined: Dec 2006
Posts: 5,154
Likes: 2
From: Ft Myers Florida
Your a friggin' genius, you don't know how many problems that solves.
Team Owner
Joined: Jul 2004
Posts: 28,463
Likes: 3,288
From: Hartford WI
