No Start, Please Help
11-15-2017, 04:03 PM
#1
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No Start, Please Help Alright, for starters, I have been reading and reading and searching and searching and have found a lot of useful threads.
Car is a stock 2001 Trans Am. I was out driving the Friday before Halloween, and it was running like a champ. Just perfect. I parked at my house and went inside for about two hours. I came back out and cranked it, and it started but it was bogging like mad, just chugging at about 500 rpm. I pressed the accelerator a bit and that didn’t really do anything. I shut it off, waited a minute, tried again with the same result. After about three tries, it wouldn’t start at all. It would crank, but not fire.
I replaced the battery because it was three years old any ways and it wasn’t a big deal. I also picked up a starter and ignition relay while at the store. Installed everything and still just cranking, no firing. I swapped the fuel pump relay with the A/C compressor relay, same result (A/C worked great with the swapped relays) (or are they fuses? No matter, I swapped them and didn’t change anything). I disconnected my fuel filter and a couple little palm fulls of gas came out, looks nice and clean and smells like gas (I have over a quarter tank in the car currently). When I turned the key to “ON” but not “Start”, no extra gas dribbled out of the fuel filter, and I’m pretty sure I can’t hear the fuel pump prime.
So, my question is, does this sound like a bad fuel pump? I know most of you are thinking “Uh, yeah, dummy” but I just want to make sure that a car running perfectly and then magically not starting sounds like a bad pump, especially in October. I’ve had one go out in the summer before but that made sense, with the heat. Are there any other points between the pump and the engine that I can check? I also checked the plug to the pump at the rear of the car behind the axle. Any help is greatly appreciated.
Car is a stock 2001 Trans Am. I was out driving the Friday before Halloween, and it was running like a champ. Just perfect. I parked at my house and went inside for about two hours. I came back out and cranked it, and it started but it was bogging like mad, just chugging at about 500 rpm. I pressed the accelerator a bit and that didn’t really do anything. I shut it off, waited a minute, tried again with the same result. After about three tries, it wouldn’t start at all. It would crank, but not fire.
I replaced the battery because it was three years old any ways and it wasn’t a big deal. I also picked up a starter and ignition relay while at the store. Installed everything and still just cranking, no firing. I swapped the fuel pump relay with the A/C compressor relay, same result (A/C worked great with the swapped relays) (or are they fuses? No matter, I swapped them and didn’t change anything). I disconnected my fuel filter and a couple little palm fulls of gas came out, looks nice and clean and smells like gas (I have over a quarter tank in the car currently). When I turned the key to “ON” but not “Start”, no extra gas dribbled out of the fuel filter, and I’m pretty sure I can’t hear the fuel pump prime.
So, my question is, does this sound like a bad fuel pump? I know most of you are thinking “Uh, yeah, dummy” but I just want to make sure that a car running perfectly and then magically not starting sounds like a bad pump, especially in October. I’ve had one go out in the summer before but that made sense, with the heat. Are there any other points between the pump and the engine that I can check? I also checked the plug to the pump at the rear of the car behind the axle. Any help is greatly appreciated.
11-16-2017, 05:35 PM
#2
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It definitely sounds like a bad fuel pump. If you disconnected the fuel line prior to your fuel filter and confirmed that no fuel is coming out when you turn the key to on, then you've confirmed the fuel pump isn't coming on.
In my 1998 Formula, the fuel pump is supplied through a 20 Amp fuse that connects to the fuel pump relay. When the ignition is turned to on/start, the PCM closes the relay and sends power to the fuel pump. If it was my car, I'd reconnect the hose at the fuel filter because it's never a good idea to create a situation where your car can just spill fuel around for obvious reasons. Once the fuel line is reconnected, I would check the fuse to ensure it isn't blown. I would then confirm the fuel pump relay is working by checking for voltage at the coil pins where it plugs in and then confirming the relay itself is good (or swap with another relay because what are chances that 2 relays are bad at the same time). If everything is good on the electrical side, I would check fuel pressure at the fuel rail Schrader valve (easy to borrow a test gauge from part shops). If I was getting no or low pressure with the key in the on/ignition position, then I would proceed with replacing the fuel pump.
The fuel pump isn't an easy change out so it's worth the effort to follow some good troubleshooting procedure before dropping the tank or cutting an access hole in the car.
Just my .02
In my 1998 Formula, the fuel pump is supplied through a 20 Amp fuse that connects to the fuel pump relay. When the ignition is turned to on/start, the PCM closes the relay and sends power to the fuel pump. If it was my car, I'd reconnect the hose at the fuel filter because it's never a good idea to create a situation where your car can just spill fuel around for obvious reasons. Once the fuel line is reconnected, I would check the fuse to ensure it isn't blown. I would then confirm the fuel pump relay is working by checking for voltage at the coil pins where it plugs in and then confirming the relay itself is good (or swap with another relay because what are chances that 2 relays are bad at the same time). If everything is good on the electrical side, I would check fuel pressure at the fuel rail Schrader valve (easy to borrow a test gauge from part shops). If I was getting no or low pressure with the key in the on/ignition position, then I would proceed with replacing the fuel pump.
The fuel pump isn't an easy change out so it's worth the effort to follow some good troubleshooting procedure before dropping the tank or cutting an access hole in the car.
Just my .02