Hey guys, i recently fixed my car from an lpg backfire, chucked some 9mm leads on and for some reason when in P or N it sits at 1000rpm, but in D or R it idles about 500rpm, when braking into a corner it drops to about 300rpm, any ideas? Also trying to find out if its legal for me to replace odometer cog myself? And lastly (for now) i done a radiator flush about a month ago, replaced my thermostat about 3 weeks ago and have issues with coolant level. All pipes are secure, unswollen and crackless. Cheers for any help.
NOTE: all vacuum lines have been checked and none are off, dont wanna adjust the throttle cable otherwise P and N will idle at 1500
No probs doing the cog as long as you don't alter the speedo reading. Try cleaning the throttle body and the TPS for the idle. Re coolant - if inlet manifold gasket is leaking coolant into engine it may also affect idle. Check radiator side tanks for hairline cracks....also renew radiator cap.
With the coolant flush, make sure you let any air out from the breather screw at the top of the thermostat.
As im still a touch new, whats the tps? I used throttle body cleaner as my butterfly was filthy, had temporary response increase, and cheers, i done the cog now just gotta set speedo needle to work again. Where are the radiator side tanks i need to check? Sorry feel so noobish lol
He's referring to the sensors on the throttle body the TPS or throttle position sensor just needs a quick blow out with some air (using a compressor, make it real breezy). When you undo the breather screw leave the car running for a few minutes till the temp. rises up, attack the breather screw with some WD-40 (it will be a bitch to undo otherwise) and just undo it by a few turns, you should notice little bubbles popping out. Leave the car running for a few more minutes, tighten up the screw and it should be right!
You gas will need a tune. It's sounds like it could be running too lean. Take it to any gas conversion place and the can give it a quick tune up in about 10 min tops.
Bleeding coolant system When you bleed your coolant system get a 2ltr coke bottle cut the bottom off. Leave the car off. Get some duct tape and rap some around the other end of the coke bottle and jam it in the radiator neck. Make sure the duct tape is in one piece and is rapped also up around the fatter part of the bottle,, as you done want any of the tape to go into the cooling system. (If you have a piece of old radiator hose that is better.) Fill the coke bottle about 3/4 with water and open up the bleed valve. You should hear air rushing out the bleed valve. When you have a full stream of coolant coming out the bleed shut the bleed valve off. I normally then start the car turn on the heater and run it until the temp is not quite 1/4 then open the bleed again and then shut off the bleed. Then remove the coke bottle you will spill some but just wash it off. Then replace the radiator cap. Run the car for a bit and check your overflow bottle has a good dose of water. SOME say to run the motor until it gets hot. I DON'T DO THIS, as you get burnt by the water because the water will start to boil as you have no pressure on the system. If all gose well the next morning when you open up the radiator it should be full. If not top it up and the check it again the next day. If you still have water in your overflow and your radiator cap is OK,, when your car is cold and you open up the radiator cap the radiator should be full. If not you must have leaks. With your idle dropping what about the isc ( Idle speed control unit ) Maybe someone else can comment on that as I don't know much about the ISC on the commodores. Hope that all makes sense***************
