Hey guys I recently just bought a 1992 Camaro RS and I am still learning the car. When I first purchased it the car would idle aroun 600-800 RPM's but the last two days the car has been idleing around 1200 RPM. Any idea why this is? Anything I can do about it? Also the car runs a little rich but all the emissions have been cut off and capped. Is there any way to correct the running rich problem without the emissions?

-Thanks,

Darren

 

Check engine light on at all? Scan for codes?

 

No check engine light and when I scaned the car no codes came up. Im clueless

 

A couple of things to test & try.

1) Vacuum hose leaks - One at a time, remove each vacuum line to the manifold or throttle body and plug the fitting to see if the idle changes. If the idle lowers, check the hose for a crack or split. If it doesn't put the hose back on and move on to the next one until you've check them all. The PCV might also leak enough to raise the idle.
2) CTS - With the engine running, pull the connection from the coolant temperature sensor (CTS). On a 305 TBI, the CTS is screwed into the manifold next to the thermostat housing toward the passenger side. If you have a 200-300 ohm resistor, you could also jump the connector to simulate 150-200 degF. If the idle lowers and it stops running rich, the CTS is probably going. A bad CTS typically tells the ECM the engine is really cold, so it raises the idle & dumps in more fuel. The CTS is easy & inexpensive to replace.

 

Hey thanks for the response I will try both of those and let you know how it goes.

Thanks,

Darren