Crank no start

HSAAGER1

MEMBER
2004 HYUNDAI SONATA
2.6L
V6
2WD
AUTOMATIC
115,000 MILES

This happens not all the time and nobody seems to have a clear answer to this.
Every couple of weeks, when I have been driving long enough for the engine to warm up and everything works fine. The car cranks but won't start for a few minutes then it starts and acts normal again for a few weeks ( one time only one day).
No engine light on battery is fine, purge valve was changed ( Hyundai dealers prognosis of the problem )
When it happens, it is always after I stopped for about 1-1 1/2 hours. Does this ring a bell?

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

The first thing that comes to mind is a crank sensor. Basically, when they get hot at times, they can cause the engine to stall or not restart.

So, if it were me, I would replace the CKP sensor and then retest the operation. Clearly if it never happens again then that was the issue.

However, if it does then we are going to have to diagnose this when the issue is happening.

When this happens, we need to start with checking voltage at the starter. If you have no voltage on the trigger wire, then we need to suspect there is a possible relay issue. So, while the engine is still not restarting, we need to jump the relay and see if it starts.

I am attaching the wiring diagram below for more detail but here are a couple guides that will help with this as well:

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

https://www.2carpros.com/articles/car-cranks-but-wont-start

Please run through this info and let us know what you find with this, and we can go from there.

Thanks

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