My old work truck died the other day and wouldn't re start. Acted like it ran out of fuel. It seems I have no spark and no fuel. Any ideas? I checked the fuses and the y seem ok. Crank sensor??
1997 C2500 Died No Start 5.7 Vortec
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Do you have a RPM Signal via Scan Data?......Does the Tachometer move while cranking?
On these old Vortecs with high mileage......The wires coming off the Crank Sensor get soaked in oil & the insulation rotts off causing short circuits.
The Distributor Gear can wear out, Does the Ignition Rotor spin while cranking the engine?
On these old Vortecs with high mileage......The wires coming off the Crank Sensor get soaked in oil & the insulation rotts off causing short circuits.
The Distributor Gear can wear out, Does the Ignition Rotor spin while cranking the engine?
The tach doesn't move while cranking. I haven't removed the distributor cap yet.
How's the fuel filter and particularly the pump. GM has been using garbage fuel pumps for decades and that's the first thing I go looking for when I see any starting issues with a Chevy. Check the fuel lines too. Anything that all you never know when the next one's going to give out I used to have an old 1988 Silverado with an engine that had undetermined miles. It ran like a clock right up until the day it wouldn't start anymore. Screwed around with it for a while and finally found out the timing chain had stretched farther than the computer could compensate🤬.
The Crank Sensor is supplied 12 vdc & a Ground......The Middle circuit/wire on the connector is the Signal Circuit.
As the engine spins, A Zero to 12 volt Square Waveform is produced. I'm guessing you don't have a scope to see this Waveform.
While cranking the engine.....Using a Multimeter hooked to ground, While probing the Signal Circuit......You should see a "Average" Voltage of around 4 volts on a working sensor.
As the engine spins, A Zero to 12 volt Square Waveform is produced. I'm guessing you don't have a scope to see this Waveform.
While cranking the engine.....Using a Multimeter hooked to ground, While probing the Signal Circuit......You should see a "Average" Voltage of around 4 volts on a working sensor.
Nick1994
$100 site donor 2024
See if the fuel pump relay is the same as the a/c and trade them. Can't remember if they're the same or not.
Had mine go out when I had my 96' C1500 5.7L.
Had mine go out when I had my 96' C1500 5.7L.
You must have fuel , compression and spark ( at the correct time ) .
Pick one and start trouble shooting . If it is OK , go to the next one .....
Some GM engines have an oil pressure switch / sensor that directly or indirectly controls the electric fuel pump .
Pick one and start trouble shooting . If it is OK , go to the next one .....
Some GM engines have an oil pressure switch / sensor that directly or indirectly controls the electric fuel pump .
On my 93 5.7 the module inside the High Energy distributer cap failed. Not sure if the Vortec had the same setup.
Originally Posted by Snagglefoot
On my 93 5.7 the module inside the High Energy distributer cap failed. Not sure if the Vortec had the same setup.
95 was the last year for TBI.
On my 93 5.7 the module inside the High Energy distributer cap failed. Not sure if the Vortec had the same setup.
95 was the last year for TBI.
Originally Posted by JP_Property
My old work truck died the other day and wouldn't re start. Acted like it ran out of fuel. It seems I have no spark and no fuel. Any ideas? I checked the fuses and the y seem ok. Crank sensor??
It seems like you have no spark or fuel, or do you KNOW you have no spark or fuel? The only way you're going to solve this is by troubleshooting. This involves testing and CONFIRMING if you have spark or fuel. Find out which one you're missing, and then figure out why it's missing.
My old work truck died the other day and wouldn't re start. Acted like it ran out of fuel. It seems I have no spark and no fuel. Any ideas? I checked the fuses and the y seem ok. Crank sensor??
It seems like you have no spark or fuel, or do you KNOW you have no spark or fuel? The only way you're going to solve this is by troubleshooting. This involves testing and CONFIRMING if you have spark or fuel. Find out which one you're missing, and then figure out why it's missing.
Thanks Clinebarger!! I'll check the crank sensor tomorrow
I confirmed the truck had no spark at the coil. Also it had very little fuel at the shrader valve on the fuel rail. I bought a $12.00 crank sensor on amazon installed it and it fired right up. Thanks for everyone's help. I can get it in my friends garage now so I can pull the engine and rebuild for project vehicle.
Without a RPM signal.....The fuel pump will not run while the engine is cranking. It will still prime, But these are notorious for not holding pressure....Be it a leaky regulator or a bad check valve in the pump.
Originally Posted by clinebarger
Without a RPM signal.....The fuel pump will not run while the engine is cranking. It will still prime, But these are notorious for not holding pressure....Be it a leaky regulator or a bad check valve in the pump.
Thanks for the help Clinebarger!,
Without a RPM signal.....The fuel pump will not run while the engine is cranking. It will still prime, But these are notorious for not holding pressure....Be it a leaky regulator or a bad check valve in the pump.
Thanks for the help Clinebarger!,
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