Mass Air Flow diagnosis
A good rule of thumb: Grams per second should equal the vehicles engine liter size at 1000 rpm when working correctly on most vehicles. It is still important though to check CFM specs on a vehicle prior to testing, some equal engine liter size at idle rpm which will be 300 to 400 rpm lower. Note: This is not a final test but a preliminary test to check basic function.
Potential Engine Damage during Transmission R&R
Many of today's automobile engines utilize complex valve and cam timing systems. These timing systems are configured to turn/rotate in the direction of ENGINE RUNNING ROTATION ONLY! If you rotate the engine in the opposite direction of running rotation during the R & R process the cam/valve timing may jump.
Many of these engines are interference type engines, some are not. An interference type engine will allow the valves to hit the pistons if the cam/valve timing is off.
If the engine is an interference type and the cam/valve timing has jumped from rotating the engine the wrong way you may hear a pop or snap when you attempt to start the engine. If so you may have just provided your customer with a FREE engine $!
Most engines run clockwise when viewed from the FRONT of the engine-crankshaft balancer/pulley. The same engine when viewed from the rear or flywheel end the rotation will be viewed as counter clockwise.
Vehicle Controllers damaged by improper jumping of dead battery!
We have recieved and verified reports of controller (Vehicle modules = BCM-VCM-PCM-ECM-TCM etc.) failure that is caused by improper jumping of battery. When hooking up another vehicle or
battery box to jump a dead battery, always turn the key off in both vehicles. If the key is in the ON position it can damage controllers when the cables are hooked up. This occurs mostly with Asian vehicles such as Nissan and Toyota, but not limited to these.
Many of you may remember the Mitsubishi vehicles with KM 175 units, had this same complaint years ago.
The proper way to hook up is this: “Turn both vehicles OFF and put keys of both vehicles in your pocket”
#1 Hook POSITIVE jumper cable clamp to positive terminal on dead battery then hook other end of jumper cable (positive) to positive terminal of good battery.
#2 Hook NEGATIVE jumper cable clamp to negative terminal of good battery, then hook other end of jumper cable (negative) to something on the engine of the dead battery vehicle , a bracket etc., making sure it is not in the way of anything that is turning or next to any other wires. An area that is solid to the block.
Start the vehicle with the good battery and or turn on battery box/charger. Run for 5 minutes before trying to start vehicle with dead battery.