2002 Chevy trail blazer

Because revving the motor makes the oil pump spin faster and therefore increases pressure. It should be stable and within specs when you are at cruising speed.

The check gauges light alerts you to the fact that one of the gauges is reading out of the normal zone. From what you have said I assume there is a problem with the oil pressure gauge in that it indicates the oil pressure is low. I suggest you remove the oil pressure sending unit and hook up a test gauge, see what the oil pressure really is. I suspect you just have a defective oil pressure sending unit.

Thank you for being very clear, most of the people on this site write very little or very poorly.

On that note, on to options. It's either (in my expert opinion) an internal engine problem, or your computer/spark plugs needs to be replaced.

Step 1: Get a tune up, (100 bucks) if already done, than I'm proud of you.
Step 2: Go to a mechanic and shell out 50-80 bucks to get a specialized computer hooked up to your car to tell you any and all of the problems with your car.
Step 3: get overcharged by said mechanic to fix it, or do it yourself and grow some chest hair.

Hope it helps.

(excuse the sarcasm, I'm bored at work solving random car problems)

Check pressure with an external pressure gauge. Proceed from the results of that test.

Hello nachelle_mar: My name is Roger and I will help you. The check gauge lamp is a warning that a failure of somekind happend. I would check the oil,coolant and fan belt. With the engine off to make sure all fluids are full and the fan belt is on the engine. Start the car and observe the gauges themselves. Are they working propperly. Charge gauge should read above the 13.5 volt level. If it is less then 12.5 volts you have a alternator problem. After warm up engine hot. Look at the tempreture gauge. If it is over 195 to 210 in tempreture. Then this would turn on the gauge lamp. Next look at the oil gauge. If the oil pressure is to low (below 12 psi.) or extremeley high or jumps around a lot. Then that would turn on the lamp also.
This should help find a solution for you. Should you need further help please just ask I would be glad th help further. Please rate the answer you received. This way I know the answer was helpful. Thank You for using Fix Ya. Roger

gauge or sender may be faulty

I have this same problem with my 2002 trailblazer; however, I goofed up and had a mechanic look at it, since I was perplexed as to what was going on with it. He told me the oil pump needed replacing and it ended up costing me around a $950. Needless to say, it still happens. A grand down the drain - it wasn't the oil pump. The oil level is always good. This generally occurs when I've run the vehicle for a while and then come to a stop. It occurs quite often during the spring/summer and doesn't happen all that much during colder months.

if its not a fuse check the speed sensor for the tach, and the oil pressure switch on the side of the engine block see if the lead came loose

oil pump might be going bad

you may have too much oil in the truck drain it and put in5 quarts of 40 weight oil