What is Limp home strategy?

Answer 1

something goes wrong with the car and u decide to try to get home under its own power. best to have it towed so you don't spend several hundred dollars more to fix what you break while limping home.

No. The strategy behind the "Limp Home" mode of operation is to ensure that the engine is still operational in case of a worst case scenario: Your stuck in the middle of a desert, cellphone is dead, rattle snake bit you and you seriously need to get to the next town. Walking isn't gonna help...

But even more so to PROTECT the engine itself.

If a critical sensor, like an air flow meter, is faulty, then the engine is at risk of running too lean. When an engine runs too lean, it means that there is more oxygen upon combustion than there is fuel to burn. That extra oxygen is now placed in a high pressure, high temperature environment and it is gonna want to react with something. That's when the Oxygen atom says to his buddy: "Hey, lets walk over to those Aluminum atoms at the bar...?". Thus when the engine runs too lean, then you could potentially burn a hole through your pistons or weld the pistons to the sleeve of your engine-block.

(You might vaguely recall from primary school science experiments that even iron burns in pure oxygen, what happens here is not too different)

For this reason the computer compensates by making sure that the engine is ALWAYS running far too rich. Hence it wont damage your car whilst driving in this mode because it is intended to protect your engine. Cant say the same for your fuel budget though... Sincerely Hein

For any other questions on this topic, feel free to contact me at: hein_kruger_1@Yahoo.co.uk