emissions control
Thread Starter
5th Gear
Joined: Jun 2021
Posts: 5
Likes: 1
From: Prospect, Ohio
emissions control
I just bought a 1984 vette that someone has removed the emissions controls off of the engine. It searches for the correct idle speed all the time. It will idle so slow it dies at times but will start right back up. It will idle between 300 rpm to 1200 rpm and idles rough. I changed the Idel speed controls which did help some but it still searches . What can I do to get a smooth and steady idle. They removed the AIR pump, blocked off the EGR and removed the switches. if anyone has any ideas I would be greatfull for the in formation.
Last edited by RDMarine; Jun 28, 2021 at 12:55 PM.
Safety Car
Joined: May 2001
Posts: 4,720
Likes: 1,625
From: Fairfax Virginia
When you get a chance you might want to be sure that your EGR and AIR systems have been deleted in the code. There are folks out there who have removed the EGR but not in the software. All would be healthier for the engine without the EGR functions.
There are plenty of folks here with the 1984 Corvettes and they know how to make them work really well!
There are plenty of folks here with the 1984 Corvettes and they know how to make them work really well!
Team Owner
Joined: Jul 2004
Posts: 28,330
Likes: 3,245
From: Hartford WI
When you get a chance you might want to be sure that your EGR and AIR systems have been deleted in the code. There are folks out there who have removed the EGR but not in the software. All would be healthier for the engine without the EGR functions.
There are plenty of folks here with the 1984 Corvettes and they know how to make them work really well!
There are plenty of folks here with the 1984 Corvettes and they know how to make them work really well!
Melting Slicks
Joined: Mar 2002
Posts: 2,873
Likes: 764
From: Sligo PA
I'm not aware of anyone who wrote PROMS for the 84. Most of us back in the day swapped in 7747 ecu's out of throttle body trucks. Everyone and there brother wrote chips for that thing. I know I removed my air pump and egr but I don't remember it ever throwing a code or having any issues with idle. But that was 20 years ago so maybe I just don't remember.
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Misfire
Random misfire on these cars can come from many places.
1. Remove the spark plugs and see that they are all the same. Lightly tan.
check the gap and reinstall.
2. next pull each plug wire and check the resistance of each wire.
check that each does not have more than 1200 ohms.
3. Next pull the pink wire off the distributor cap and make sure the wire contacts the blade firmly.
4. Remove dist cap and check the center pin and the rotor . Look at the rotors edge that is farthest from the center, that it’s not burned back. Inspect the cap for cracks, and plug studs for carbon tracking.
5. Unclip all the injectors and measure the resistance, and make sure they are all close.
start there, look around for loose or broken connectors too
1. Remove the spark plugs and see that they are all the same. Lightly tan.
check the gap and reinstall.
2. next pull each plug wire and check the resistance of each wire.
check that each does not have more than 1200 ohms.
3. Next pull the pink wire off the distributor cap and make sure the wire contacts the blade firmly.
4. Remove dist cap and check the center pin and the rotor . Look at the rotors edge that is farthest from the center, that it’s not burned back. Inspect the cap for cracks, and plug studs for carbon tracking.
5. Unclip all the injectors and measure the resistance, and make sure they are all close.
start there, look around for loose or broken connectors too
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