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Misfiring, Stalling, Fuel Pump Stays On!

  • Thread starter Thread starter DRock9
  • Start date Start date Mar 2, 2007
D

DRock9

New Member
Aug 22, 2006
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Mar 2, 2007
#1
  • Mar 2, 2007
  • #1
I have a 1990 Mustang GT with 120k miles, mods in sig.

This morning I am pulling into the center of town and the car starts to misfire, didn't know at the time, and then stalled...I thought I let the clutch out too fast so I started it back up and it would just crank over but it wouldn't start. I finally got it started after holding the ignition for about 10 seconds and then realized something was wrong. The car idled fine, no problem, but once I tried to accellerate it would missfire and run REALLY rough until it stalled...it seemed to only do this under load. I made it half way up the hill to my school and had to stop, I knew it wouldn't make it to the top so I flipped my emergencies on and let all 100 cars behind me pass. I waited till there was a big gap in traffic then revvd it really high in neutral and every so slightly slipped the clutch after putting it into first and I made it so school this way. I thought at first maybe it was an ignition problem but then when I parked and turned off my car the fuel pump was still running and it will not shut off.

About a month ago I put in like a gallon or two of gas, not knowing it was mixed with oil, into the tank because I ran out and the car would not start. I ended up putting more gas in to get it to run, then went right to the gas station and put $40 of premium in it to dilute it. It ran fine for this whole time and I just put seafoam through my car about 400-450 miles ago, gas tank, oil, and vacuum line. I was supposed to change my oil yesterday but the weather would not let me do so so I figured I could go till today until I changed my oil but then this happens.

I am thinking maybe it has something to do with the seafoam but what would that have to do with my fuel pump staying on? Could they be two unconnected problems but just a bad coincidence they happen at the same time?

I am not sure what is wrong but I am going home today right after school and I am going to change my oil and call up my mechanic.

Thanks for any help!
 
D

DRock9

New Member
Aug 22, 2006
359
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0
Mar 2, 2007
#2
  • Mar 2, 2007
  • #2
My Dad picked the car up today while I was in school and he said it ran fine until he went through a puddle, and then it would sputter and stall... I cant think of an explanation for this. I have the stock intake so nothing should be getting inside the motor, anyone know why this might happen?

Thanks!
 
D

DRock9

New Member
Aug 22, 2006
359
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0
Mar 2, 2007
#3
  • Mar 2, 2007
  • #3
Turned out to be a bad fuel filter relay, so they replaced it and it is fine.
 

blownLX5oh

New Member
Dec 3, 2006
42
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0
Mar 2, 2007
#4
  • Mar 2, 2007
  • #4
Sounds like you have a bad fuel pump relay......I'd start there and move to the fuel filter....how many miles since the last fuel filter change?

Bobby
 

blownLX5oh

New Member
Dec 3, 2006
42
0
0
Mar 2, 2007
#5
  • Mar 2, 2007
  • #5
SNAP! I didn't see your last post....(Hey I was right too!!!)

Anyway, glad you got it fixed ;-)

Bobby
 
D

DRock9

New Member
Aug 22, 2006
359
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Mar 2, 2007
#6
  • Mar 2, 2007
  • #6
Thanks! It's running really good right now, my Dad paid the bill for me but I am still a bit peeved because they charged us $75 for a set of CARQUEST ignition wires when I could have gotten Ford ones for $40...

Oh well it's running good I guess, surges a bit at idle now when it is cold but whatever.
 
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