I have a bone stock 91 RS Camaro. 305tbi/auto. Warmed up in PARK it idles at about 600-650rpm`s. In drive it idles at about 500rpms. I know that the idle speed is to low. What could cause this to be happening? Ive read my manual and it says that the idle speed is computer controled. So I havent messed with anything. I checked my Ignition Timing and it is at 0 with that one wire, yellow/white or brown/white, disconnected. Thats the way my manual says to check the timing. After I reconnect that wire my Initial timing goes to 10*advanced at idle in Park.
I am not flashing any codes. Im stumped.
Any advice would be greatly appreciated.

JC

 

could be the PCV valve. try changing out the basics like air filter, breather, PCV and then tell us what happens. If these thinggs go bad they won't trigger and codes because they are not ECM connected. your total investment will probably be about $25

A lady came into my shop with a chrysler that was doing the same thing. idled @ 400 and drove (i don't know how) at 150.

I swapped her PCV and all was great.
Idled at 650 and drove at 550.

 

I'm still battling the same beast (sometimes I idle at 500, sometimes 1250!). I got the thing to be at 700 or so more often by replacing a few leaky vacuum hoses. Maybe its something worth checking? Keep us posted if you figure it out.

 

Yeah! but he aint got no MoPar! Your throttle body has a throttle position screw also. Right front and it may have a cover on it wich can be removed. Inside the hole there is a torx head screw, turn it clockwise a little should be good for a few rpm. There is still mech. parts that wear down especialy on a car with 80,000 mi. or more, and they need to be reset. Good luck!

 

Isn't that why they put sensors on cars? to compensate for worn parts? This is nothing major for him to have to start turning screws just yet. that could make something else happen like excessive gas consumption. let's see what happens when he swaps out the basic breathing elements.

 

Hey, Were only talking 150 rpm. and the adj. is free. I had the same problem on mine and it cured the problem. Not to discount your idea! New filters and vacuum line check works to.

 

you get what you pay for

 

these cars have a pretty low idle speed. If it isnt causing any problems and it idles good in gear its probably nothing to worry about.

 

you're totally right. It just dawned on me to look in my chiltons at the chart for his (and mine) both of our cars. here's what it says.

91
VIN : F&E
Engine Displacement (cc): 5.0 (5011)
Spark plug gap : .035
Ignition Timing (for VIN E only): Man. Trans. 6B / Auto. Trans. 6B
No spec. for VIN F
Fuel pump: VIN E 9-13 / VIN F 41-47
idle speed: 600 rpms
Valve clearance: In. Hyd. Ex. Hyd.

These specs are for both VIN's. I trust chilton's. haven't steered me wrong yet.

And there is his answer. There is nothing wrong with your car to begin with. Your fine. Cruise on and cruise happy. and smoke a RlCER for me