O2 sensor
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O2 sensor
82 vette I bought never came with O2 sensor hooked up put new headers on an left it off and took all admission off car ran find and idle find , so after adding heads and cam n renegade intake and changing fuel pump 85" car is running lean at 4800 rpm on dyno still wanting more fuel have not rebuilt or change regulators on tbi's yet
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Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
Of course it's starving for fuel. You can't run an EFI system without O2 sensors and all other sensors hooked up and operating. Without the O2 sensors, or any other sensor not hooked up and providing input to the ECM, the system is operating in "limp-home" mode, which is only intended to get you safely off the road until you can fix it. You have to set it up right - it's been hacked. Fix it.
Last edited by lars; Nov 22, 2019 at 06:42 PM.
Drifting
Joined: Aug 2019
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Why isn't your Check engine light on? You should get a scan tool that displays data, not just codes, just to make sure what the ECM is doing.
Just a thought, how was the car running before you made the changes? Just in case, on board diagnostics for GM started in 1979. Each division had their own connector which drove techs crazy, In 1981 they all had the same 5 pin connector for diagnostics, and in 1982, because of the faster computers, they went to a larger connector with more pins. And there are many scan tools that will give you data. I have 4 tools that work. You really need to have/borrow one to perform diagnostics. To diagnose a vehicle by reading codes is just not good. IMHO.
Just a thought, how was the car running before you made the changes? Just in case, on board diagnostics for GM started in 1979. Each division had their own connector which drove techs crazy, In 1981 they all had the same 5 pin connector for diagnostics, and in 1982, because of the faster computers, they went to a larger connector with more pins. And there are many scan tools that will give you data. I have 4 tools that work. You really need to have/borrow one to perform diagnostics. To diagnose a vehicle by reading codes is just not good. IMHO.
Last edited by Mrvettenick; Nov 23, 2019 at 05:55 PM.
