90 Accord EX with auto trans,engine will crank for 2-4 seconds and not fire.

After that 1st try, I pause a few seconds and then the car will always fire on the 2nd try and usually as soon as I turn the key.

This always happens when the car sits ouside overnight.
After the car runs and is warmed up it will fire everytime as soon as I turn the key.

When the cold engine does fire, it feel like it stumbles for a split second.

It will always crank and fire when cold but never on the 1st attempt.

Other than that the car idles and runs fine under all conditions.

Any ideas on what might be causing the long cranking?

I'm thinking the fuel pressure is dropping off over night, possibly a fuel pressure regulator failing.

Possibly a bad TW sensor?

Any ideas and how to diagnose?

Thanks.

 

Check for engine/transmission codes. See the procedure in the DIY section on How to check CEL codes.

Try turning the key to the II position, but do not try to start the car. Listen for the fuel pump to prime for about 2 seconds while the check engine light is doing the bulb check.

Also, are the maintenance items up to date like the distributor cap, distributor rotor, and the spark plugs? Always use the NGK plugs recommended in the owner's manual. Other spark plugs can cause ignition problems on hondas.

 

Checked for stored codes by jumping the 2P connector. None found.
Turned key on and check engine light comes on for 2-3 seconds and then goes off.

Did this about 10 times and I can hear the fuel pump make a hum but also hear a gurgling sound as if the fuel return line is sending air rather than fuel back to the tank.

I'm thinking the fuel system is losing pressure when the car sits overnight.
I tried to prime the system by turning the key on and off about 10 times and heard the fuel pump make noise each time. Then tried to start the car and it cranked for about 5 seconds but did not fire. Tried again and as usual and it fired within 1-2 seconds. Every time it starts when cold, it stumbles for a split second then goes to fast idle as normal.
No stumbling on warm starts and it also fires as soon as the key is turned.

I replaced the spark plugs(NGK oem) last month and the distributor cap and rotor were cleaned and inspected. Timing set at 14 degrees BTDC. I did all necessary maintenance as needed to get the car to pass smog and it idles and runs great.
I'm only concerned that something is about to fail and don't want to get stranded.

The main relay solder joints failed a few years back so I soldered those and it been fine since. I also replaced the Ignition coil (oem honda) around the same time. Electrical portion of ignition switch replaced (oem honda) 2 months ago to cure a start and die condition.

Last month, I had to drill the plugs in my EGR ports and recall seeing a slight amount of wet fuel when I pulled the vacuum supply line to the fuel pressure regulator.
I will pull that hose again today and check that out.

 

Pulled the vacuum hose last night and did not see any fuel. That's good.
I must have seen the fuel when I removed the fuel pressure regulator to gain access to the EGR port plugs.

Last night at 6pm, I turned the key on and off 10 times to listen to the fuel pump.Sounds were normal with no gurgling.

Turn the key to start and the car fired up immediately with no long cranking attempt.The car had sat all night and all day without being started.

Now I'm not sure if this is a fuel delivery/pressure problem or an ambient temperature problem causing the long cranking on a cold start.

I will try the same procedure tommorrow morning when its colder.

Will also check for static fuel pressure after the car has sat overnight, and then again after I prime 10 times with the key.

Which location is best to crack a bolt loose? At the fuel filter or on fuel manifold near the pressure regulator?

Thanks.