1997 Monte Carlo when driving 55-60 motor drops down to 34-40mph

Probably your ignition switch or a fuse.

have to drop the trans pan, another way to flush your trans is to unhook the upper trans line from the radiator put a rubber hose on it run to a bucket and start car then shut it off as soon as it runs little slow n measure what came out n put exact amount back in

have a coolant pressure test done. Have the radiator cores checked for blockage. Sometimes when an engine has sat for a period of time, rust and scale form in the water jackets of the engine. ON running ,this breaks away and blocks the cores of the radiator Other times the old motor tolerates a partially blocked radiator when a relative new motor needs all the cores free to maintain the temperature.

Shakes upon acceleration is definitly an axle, quite common!

Go here for instructions on this entire job. www.alldatadiy.com

Could be bad fuel pump or plugged fuel filter.

Hi;
If your engine cools down when moving fast, you either have a problem with your water pump or your electric fans that cool off your radiator and a/c condenser. This is controlled by a temperature switch, but these fans should kick on instantly when A/C is selected.

If there is nothing else wrong with the system you just need to drive it over 25mph for more than 2 minutes. If you slow down below 25mph then you will have to start over. I would recomend getting on the freeway. Don't go over 60mph though, that will make it reset also. If it still says -40 after you are sure you have met the time and speed criteria. Then there is still a problem in the system. Make sure the connector at the temp sensor is clean and the terminals are good.

sulphur smell either bad o2 sensors or a bad cat

negative any metal part of engine wiggle the cable to have good contact that it cheers pierre