Hi,
Ever since replacing my fuel pump which didn't need to be replaced(it aint broke but I fixed it

), I've had an intermittent starting issue and I've never figured out the cause.
When the car is cold there is a chance it will crank for about 10-15 seconds then start.
When the car is hot and has been sitting for 15-20 mins, for eg. when I run into the shop to grab a few things, there is also a chance it will take 10-15 seconds cranking before it starts.
When I turn the car off then back on again, it fires up almost instantly as if the problem doesn't exist which is why I figured fuel pressure.
At first I thought maybe it's a fuel delivery issue, and perhaps it still could be but I'm not sure so I've created this post to gather some advice on what I should check next.
Below is a list of things I've already done to try figure out what could be causing this issue.
- I've replaced the fuel pump with the teabag on the end.
- I've replaced the internal fuel filter of the fuel pump assembly.
- I've checked fuel pressure to the fuel rail.
- I've cleaned each injector and tested each one for pressure(they all spray).
- I've turned the key a few times to activate the fuel pump to ensure pressure is built up.
With all of those things done, nothing has changed. A while back my car died in traffic with a p0106 error code regarding the map sensor but I haven't replaced it($375 OEM) and I haven't had that issue since(car has never died on me since owning it other than that one occurrence so possibly another issue altogether related to map sensor?)
Could it be a crank angle sensor or fuel pressure regulator that has problems? I'm not too sure what else I can check without specialist tools and I want to check everything I possibly can before getting fed up and taking it to a mechanic lol.
Any helpful advice is greatly appreciated, thanks!
