1981 Corvette - Idle/Accelerator
Thread Starter
Cruising
Joined: Jun 2022
Posts: 11
Likes: 0
1981 Corvette - Idle/Accelerator
Hello Everyone!
Backstory:
10 days ago I got my Corvette to idle and rev up (via gas pedal) after sitting for 24 years. It idled high until I tapped the gas then it slowed down. I just tapped the gas and let it run until the thermostat opened up. Da da duhhh coolant leak. I moved the car to a dry spot after it cooled off and let idle again so I could find the leak. After 5 minutes of idle time i found it.
So I did the right thing and ordered new coolant hoses while I have been on vacation. Since it idled a little rough at the end I decided to I’d do spark plugs, and spark plug wires if needed. Ordered those too and threw in new belts while I was at it.
Todays project: belts and coolant. Done and done.
Crank the engine and after a few seconds it fired up. 10 seconds later it died while idling. Fired it again and idled great then sputtered. So I tapped the gas very lightly. Instantly died. Repeated that one more time. Car instantly starts on demand. But fails to idle for 10+ seconds and any input on the pedal is instant shut off.
Last week the pedal only revved the engine as it should.
Tomorrow’s Project: Spark Plugs and Wires (if needed)
I was hoping to move in to my non existent brakes. But it seems that will need to wait….
Any ideas?
Backstory:
10 days ago I got my Corvette to idle and rev up (via gas pedal) after sitting for 24 years. It idled high until I tapped the gas then it slowed down. I just tapped the gas and let it run until the thermostat opened up. Da da duhhh coolant leak. I moved the car to a dry spot after it cooled off and let idle again so I could find the leak. After 5 minutes of idle time i found it.
So I did the right thing and ordered new coolant hoses while I have been on vacation. Since it idled a little rough at the end I decided to I’d do spark plugs, and spark plug wires if needed. Ordered those too and threw in new belts while I was at it.
Todays project: belts and coolant. Done and done.
Crank the engine and after a few seconds it fired up. 10 seconds later it died while idling. Fired it again and idled great then sputtered. So I tapped the gas very lightly. Instantly died. Repeated that one more time. Car instantly starts on demand. But fails to idle for 10+ seconds and any input on the pedal is instant shut off.
Last week the pedal only revved the engine as it should.
Tomorrow’s Project: Spark Plugs and Wires (if needed)
I was hoping to move in to my non existent brakes. But it seems that will need to wait….
Any ideas?
Last edited by Mmtuckerr; Jul 3, 2022 at 12:04 AM.
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Cruise-In VIII Veteran
A few. First, fix the Brakes. No point in making it go if it can't stop.
You know that the engine is at least not knocking and carrying on after sitting all those years, So that's a good thing.
Fix the brakes. Drop the gas tank and flush and clean it well. Blow out the fuel lines between the fuel pump and the tank.
Blow out the fuel line from pump to carb.
Rebuild the carburetor. sounds like you've gotton gunk in it.
And it's been sitting for years. I would have cleaned the entire fuel system before even trying to start it.
Change all the fluids. Diff, trans, engine, coolant and power steering fluid.
Then, when you have brakes. Start it again.
You know that the engine is at least not knocking and carrying on after sitting all those years, So that's a good thing.
Fix the brakes. Drop the gas tank and flush and clean it well. Blow out the fuel lines between the fuel pump and the tank.
Blow out the fuel line from pump to carb.
Rebuild the carburetor. sounds like you've gotton gunk in it.
And it's been sitting for years. I would have cleaned the entire fuel system before even trying to start it.
Change all the fluids. Diff, trans, engine, coolant and power steering fluid.
Then, when you have brakes. Start it again.
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
wow, 24 years?
no run?
what did you do before starting.
does it have the check eng system?
does it light when key to run and go out when running?
can you keep eng running by working the throttle?
no run?
what did you do before starting.
does it have the check eng system?
does it light when key to run and go out when running?
can you keep eng running by working the throttle?
Thread Starter
Cruising
Joined: Jun 2022
Posts: 11
Likes: 0
Siphoned the tank, and lines. All fluids changed etc. Hand cranked the engine with oil in each cyclinder. Let it sit for a day then it ran perfectly. Smoked a little as it brought the rings back to life but after about 3 minutes idling it was perfect. I thought I got everything out of the fuel lines but that may not be the case. Going to do it again tomorrow as my fuel gage is broken anyways. But I think it is the fuel system as it fires up and idle great. It just slowly dies.
Thread Starter
Cruising
Joined: Jun 2022
Posts: 11
Likes: 0
A few. First, fix the Brakes. No point in making it go if it can't stop.
You know that the engine is at least not knocking and carrying on after sitting all those years, So that's a good thing.
Fix the brakes. Drop the gas tank and flush and clean it well. Blow out the fuel lines between the fuel pump and the tank.
Blow out the fuel line from pump to carb.
Rebuild the carburetor. sounds like you've gotton gunk in it.
And it's been sitting for years. I would have cleaned the entire fuel system before even trying to start it.
Change all the fluids. Diff, trans, engine, coolant and power steering fluid.
Then, when you have brakes. Start it again.
You know that the engine is at least not knocking and carrying on after sitting all those years, So that's a good thing.
Fix the brakes. Drop the gas tank and flush and clean it well. Blow out the fuel lines between the fuel pump and the tank.
Blow out the fuel line from pump to carb.
Rebuild the carburetor. sounds like you've gotton gunk in it.
And it's been sitting for years. I would have cleaned the entire fuel system before even trying to start it.
Change all the fluids. Diff, trans, engine, coolant and power steering fluid.
Then, when you have brakes. Start it again.
I think my fuel system flush may have missed something so I’m going to check both fuel filters tomorrow while I do spark plugs.
I have done everything mentioned but rebuild the carb. I’ll probably make that my Sunday job this weekend if it needs it.
sorry about the delayed response the lady has kept me busy the last 2 days around the house.
Last edited by Mmtuckerr; Jul 5, 2022 at 03:28 PM.
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
I cleaned the entire fuel system. The tank was clear when I siphon and flushed it but that doesn’t mean something didn’t break lose. The mechanical pump could need replaced so I’ll inspect there. But the tank and lines you mentioned were cleaned. Since it starts up perfectly every time I think it would be more the fuel pump than the carb.
I think my fuel system flush may have missed something so I’m going to check both fuel filters tomorrow while I do spark plugs.
I have done everything mentioned but rebuild the carb. I’ll probably make that my Sunday job this weekend if it needs it.
sorry about the delayed response the lady has kept me busy the last 2 days around the house.
I think my fuel system flush may have missed something so I’m going to check both fuel filters tomorrow while I do spark plugs.
I have done everything mentioned but rebuild the carb. I’ll probably make that my Sunday job this weekend if it needs it.
sorry about the delayed response the lady has kept me busy the last 2 days around the house.
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