need help with engine light problem

[drewk420]

1991 honda civic dx My check engine light comes on and cause my car to run at a max of 3500 rpm. think it might be a mass airflow problem. I rigged the air box up so that it was getting direct air from the engine compartment. stupid sound trick. But i'm installing a new intake now and wanted to know if i need to reset the ecu after doing so that i dont have a mass air flow problem

[travagliante]

mmmm. sounds simmilar to my problem,
crank angle sensor.

Heres how to diagnose to see the problem.

1. Pull the carpet on the pass left side to reveal the ecu.
2. Turn your key on but dont start car
3. Count the number of flashes.


If you count 4 the crank angle sensor went bad, meaning you need to get a new distributor, or you knocked a wire lose when installing intake.

[drewk420]

what about a mass air flow issue with the inatake change do i need to do anything with that

[travagliante]

Check the ecu first, how many lights flash in a sequence how many short flashes until a pause.

[91civichatch2571]

Yea, like he said, pull your carpet back from the passenfer side floor where their feet would be. There will be a goldish plate with a whole in it. Turn your key to the on position, the LED in the whole will flash once to show that its getting power. If it flashes any after that, count how many times it flashes without pausing. This actually tells you exactly what is wrong with the car if anything. When you find out how many times its flashing, come back to us and we'll help you right out.

[Hilikus Funkin]

Our cars dont have mass air flow sensors dude, listen to what theyre saying.