1990 5.7 TPI in 1937 Chev will crank over but not start
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1990 5.7 TPI in 1937 Chev will crank over but not start
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1990 5.7 TPI with Painless wiring harness
Vats - Small plug in 3 wire to computer that allows car to run
Car has been running for 10 years. Replaced in tanke fuel pump once in ten years. New Bosch injectors about 4 years ago.
Drop car home. Next morning cranks over but will not start.
Have performed the following
1. Disconnect battery for an hour and re try
2. Left ignition on for 11 minutes and tried to start
3. Fuel pump cycles on with ignition and shows 45 psi on ignition. When cranking fuel pump shows 55 psi
4. Spark at spark plugs
5. 12 V at both wires on injectors
6. Nodes light - When car is crank lights up once for a fraction of a second and then nothing. Appears injectors are not being triggered.
Any suggestions on what to look at next
1. Could it be the 3 wire plug in for the VATS that is acting up. If this was malfunction would the car still crank over?
2. Could it be the computer?
3. Would the distributor cause no injection?
1990 5.7 TPI with Painless wiring harness
Vats - Small plug in 3 wire to computer that allows car to run
Car has been running for 10 years. Replaced in tanke fuel pump once in ten years. New Bosch injectors about 4 years ago.
Drop car home. Next morning cranks over but will not start.
Have performed the following
1. Disconnect battery for an hour and re try
2. Left ignition on for 11 minutes and tried to start
3. Fuel pump cycles on with ignition and shows 45 psi on ignition. When cranking fuel pump shows 55 psi
4. Spark at spark plugs
5. 12 V at both wires on injectors
6. Nodes light - When car is crank lights up once for a fraction of a second and then nothing. Appears injectors are not being triggered.
Any suggestions on what to look at next
1. Could it be the 3 wire plug in for the VATS that is acting up. If this was malfunction would the car still crank over?
2. Could it be the computer?
3. Would the distributor cause no injection?
Joined: Nov 2008
Posts: 2,093
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From: Milwaukee
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: 1990 5.7 TPI in 1937 Chev will crank over but not start
1. You probably have the starter wired up so the VATS won't affect the starter. So it most likely will crank.
2.Possibly
3.Yes, the distributor is the 'crank' and 'cam' sensor on this style computer. If the ign module isn't sending the signal to the ecm, the ecm will not pulse the injectors.
2.Possibly
3.Yes, the distributor is the 'crank' and 'cam' sensor on this style computer. If the ign module isn't sending the signal to the ecm, the ecm will not pulse the injectors.
Re: 1990 5.7 TPI in 1937 Chev will crank over but not start
Do you have a SES light hooked up/OBD port hooked up? If so, you can see if the ECM is throwing any VATS related trouble codes.
This might be helpful for you, you'll just have to adjust for your application a little since you don't have a VATS box:
https://www.thirdgen.org/vats_passkey_system/
This might be helpful for you, you'll just have to adjust for your application a little since you don't have a VATS box:
https://www.thirdgen.org/vats_passkey_system/
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Posts: 4,624
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Re: 1990 5.7 TPI in 1937 Chev will crank over but not start
12V at both wires on each injector?
I believe only the pink wire should be showing 12V. The other wire is a switched ground within the ECM I believe.
What you could do is (after priming the system) disconnect the fuel pump relay, then crank the engine over and see if the fuel pressure drops. That would at least tell you the injectors are firing. If the pressure doesn't drop, then the injectors most likely are not firing.
You could also get a friend to crank the engine over while you put your finger on one of the injectors... you should be able to feel the solenoids opening and closing.
If the injectors are not firing, most likely something is up with the VATS module. If you're getting spark, it's most likely not the distributor.
I believe only the pink wire should be showing 12V. The other wire is a switched ground within the ECM I believe.
What you could do is (after priming the system) disconnect the fuel pump relay, then crank the engine over and see if the fuel pressure drops. That would at least tell you the injectors are firing. If the pressure doesn't drop, then the injectors most likely are not firing.
You could also get a friend to crank the engine over while you put your finger on one of the injectors... you should be able to feel the solenoids opening and closing.
If the injectors are not firing, most likely something is up with the VATS module. If you're getting spark, it's most likely not the distributor.
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Dec 14, 2015 08:57 AM