i have an el ghia v8 and just wondering y the oil guage fluctuates alot when stopped at lights when car is warm?

I think you will find that it is an oil pressure guage!

When you are at the lights, the pressure inside the engine isnt as high as when you are in normal driving condition.

Hope this helps.

my oil pressure guage drops when im sitting at the lights, esp. on hot days ..

just a normal thing, Think some guages are a bit more senitive than others.

I've studied this a bit. Have you noticed that while the oil guage drops down, the battery gauage drops down a bit too. Hovering around the 12 volt mark.
When it's hot, and you are stopped at lights. You might have the air-con going, stereo going, brake lights on as your braked and in drive. Thermo fans are going, it's a drain, and when I put a drain on my system, it too sends the oil guage a bit low.
When the needle on the battery guage gets up to around the 13 or above mark, oil pressure guage stays on half way.

To test this theory, get in the car and start it. With eye's on the oil pressure guage, place it in drive with foot on brake. Put air-con on, lights and high beams, and see if the electical system drain drain moves the oil needle. Turn them off, and it should rise straight away.

Am I right or just completely crazy?