It cranks over and sounds like it wants to start but wont?

ALBIE78M

MEMBER
2002 MAZDA 626
4 CYL
FWD
AUTOMATIC
108,525 MILES

I have a mazda 626 it had 3 codes in the computer one was p0117, p0125, and p0300 I have replaced the plug wires and plugs and filled the radiator and put jumper cables on the car it cranks over and sounds like it wants to start but wont any other troubleshooting hints of what to look at the time belt looks good and timing appears to be correct the car just shut off while driving and is the engine an interferance fit engine so if it did jump time would the valves go into the pistons

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

Here are the codes:
P0117 - ECT circuit low input
P0125 - Excessive time to enter closed loop fuel control
P0300 - Random misfire detected

It sounds like you have a faulty crank position sensor. This is why you are getting these codes. As the engine cranks for an extended period of time it triggers the P0125.

When a crank sensor goes bad, it will produce faulty or no signal to the ECM and and engine will not start. And it can also stall the engine at random times.

The crank sensor is located on the lower part of the engine (see diagram).

You might find these articles helpful:

https://www.2carpros.com/articles/how-a-crank-shaft-angle-sensor-works
https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor
https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

I have attached diagrams for your reference.

Please let me know of any questions.

Thank you.

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