Ok, I can't figure out what is wrong. A while ago my 76 (79 engine) stopped working. For a couple of days it was sputtering badly with smoke before it would finally run fine and the smoke would go away. Then soon after it just stopped running altogether. Now the engine turns over and there are no sounds of explosions. I have checked the fuel pump pressure (after the fuel filter) and it is up around 30. I checked to see if I was getting sparks. Indeed I am. I also checked the #1 injector to see if it was getting voltage and it is; so is the cold start valve. Here are some curious things I see: When I tried to relieve the fuel pressure by ejecting fuel from the cold start valve, nothing came out. There is a little gasoline on the head near the #1 fuel injector, but not much. The oil level is a bit above the H line. Any ideas? Anyone??? PLEASE!
76 won't start
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·Duckboy,
You have just described to a T the same problems I am having with my 77. It either runs like a bat out of **** or it is sputtering and throwing out a blinding smoke. I have replaced everything on the F.I. and ignition except for the brain and the throttle sensor. In my case I think it may be the ECU. I kicked it the other night and the car immediately ran well. When it runs bad is sputters, smokes, stalls and won't start again, floods then restarts when it has cooled down.
One word of caution: When mine has been smoking it is because it is being flooded. Check your oil to make sure it does not smell like gas. If it does, it has been watered (gased) down and should be changed.
IWhen you find a solution to your problem. Please drop me a line. This replacing parts is killing me. Thanks. John
You have just described to a T the same problems I am having with my 77. It either runs like a bat out of **** or it is sputtering and throwing out a blinding smoke. I have replaced everything on the F.I. and ignition except for the brain and the throttle sensor. In my case I think it may be the ECU. I kicked it the other night and the car immediately ran well. When it runs bad is sputters, smokes, stalls and won't start again, floods then restarts when it has cooled down.
One word of caution: When mine has been smoking it is because it is being flooded. Check your oil to make sure it does not smell like gas. If it does, it has been watered (gased) down and should be changed.
IWhen you find a solution to your problem. Please drop me a line. This replacing parts is killing me. Thanks. John
Try these tests.
Remove the return line from the fuel rail and replace it with a length of tubing then put the loose end in a suitable container. Remove the small gauge wire from the starter solenoid and hold the key in the "start" position for 5 seconds. The fuel pressure should rise to 42 PSI. Does fuel come out the return line into the container?
Replace the return fuel line.
Remove the cold start valve from the fuel hose going to it and put the tubing you used on the return line on the fuel hose. Hold the key in the "start" position for 5 seconds. Does fuel come out the line into the container? If not you have a plugged fuel rail.
If you get fuel coming out of the hose reconnect the cold start valve to the fuel line. Build a set of jumper wires to go from the cold start injector and the battery. Pressurize the fuel system and then touch the wires to the battery. Does fuel come out of the cold start valve?
Put the wire back on the starter solenoid and using a mechanics stethoscope listen to each injector while someone else cranks the engine over. Do you hear the injectors clicking.
Disconnect the negative battery terminal.
Remove the connector from the ECU and using break parts cleaner spay the pins of the ECU and the harness connector to remove any crud from them. When the break parts cleaner has evaporated put some silicone die-electric grease on the pins of the harness connector and reassemble.
Reconnect the negative battery terminal and start the engine.
Check the battery voltage while cranking if it is lower than 9 volts the ECU will not function correctly.
Spray some Quick-Start into the intake through one of the vacuum line nipples. Does the engine start?
If the test above for the functionality of the cold start valve was good then have someone try and start the engine while you hold the cold start valve jumper wires to the battery. If the engine starts check for clicking of the injectors with the stethoscope.
If you do not hear any clicking AND you have more than 9 volts at the battery while cranking the ECU is likely bad.
Wayne Monteath
Masham, Quebec.
Remove the return line from the fuel rail and replace it with a length of tubing then put the loose end in a suitable container. Remove the small gauge wire from the starter solenoid and hold the key in the "start" position for 5 seconds. The fuel pressure should rise to 42 PSI. Does fuel come out the return line into the container?
Replace the return fuel line.
Remove the cold start valve from the fuel hose going to it and put the tubing you used on the return line on the fuel hose. Hold the key in the "start" position for 5 seconds. Does fuel come out the line into the container? If not you have a plugged fuel rail.
If you get fuel coming out of the hose reconnect the cold start valve to the fuel line. Build a set of jumper wires to go from the cold start injector and the battery. Pressurize the fuel system and then touch the wires to the battery. Does fuel come out of the cold start valve?
Put the wire back on the starter solenoid and using a mechanics stethoscope listen to each injector while someone else cranks the engine over. Do you hear the injectors clicking.
Disconnect the negative battery terminal.
Remove the connector from the ECU and using break parts cleaner spay the pins of the ECU and the harness connector to remove any crud from them. When the break parts cleaner has evaporated put some silicone die-electric grease on the pins of the harness connector and reassemble.
Reconnect the negative battery terminal and start the engine.
Check the battery voltage while cranking if it is lower than 9 volts the ECU will not function correctly.
Spray some Quick-Start into the intake through one of the vacuum line nipples. Does the engine start?
If the test above for the functionality of the cold start valve was good then have someone try and start the engine while you hold the cold start valve jumper wires to the battery. If the engine starts check for clicking of the injectors with the stethoscope.
If you do not hear any clicking AND you have more than 9 volts at the battery while cranking the ECU is likely bad.
Wayne Monteath
Masham, Quebec.
Re: Try these tests.
try relacing the fuel filter. thats has been one of my biggest problems for no start and not getting fuel to the rail.
try relacing the fuel filter. thats has been one of my biggest problems for no start and not getting fuel to the rail.
Re: Try these tests.
I had the same problem with my 77 also. It did not run for 8 months, and it took 3 shops before someone could finally fix it. On mine, it was a defective ecu, and some of the wires on the wiring harness had to be replaced. Also had to have the fuel injector connectors replaced.
I had the same problem with my 77 also. It did not run for 8 months, and it took 3 shops before someone could finally fix it. On mine, it was a defective ecu, and some of the wires on the wiring harness had to be replaced. Also had to have the fuel injector connectors replaced.
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