I have an Acura 2000 TL. It only starts with an extended crank after about 8 or 10 cranks. When I put the key in the ignition ON position and waited for few seconds, it started right away. I shut off the engine and tried to start right away, the car gave 8 or 10 cranks and then starts.

I changed the fuel/main relay and the problem didn't go away. I changed the battery to make sure that it has good amperage. The problem did not go away.

It seems the car is taking time to prime the fuel or the fuel pressure is not retained after turning off the engine. The first thing I could think of is the fuel return valve and I don't know where it is located. The second guess is fuel pressure regulator. If that is bad why the car doesn't start right away after turning off the engine and restarting it within 2 seconds. The third guess is the fuel pump. I used Seafoam a couple of times and it did not improve the delayed starting condition.

Can someone help me to diagnose the problem with the circumstances I had mentioned above?

 

Seafoam has to be used correctly to really clean injectors and fuel path
How did you apply it? thru the gas tank?

new battery was fully charged??, not off the shelf after stored awaiting sale or one sitting in your garage?

the FPR can be the solder under the box

the 3 things you listed as suspect are the 3 least likely failures we actually experience!

 

check for fuel pressure. The car should only have an extended crank if it has sit for a LONG time. There is a check valve that keep the pressure up even after you turn the car off. it sounds like you have low fuel pressure and if you wait a few seconds after turning the key and it starts right up you need to check the fuel pressure and troubleshoot the issue.

 

What does the temperature gauge show while the extended cranks ?
Hot Cold or in between.
I recently had the hot start issue but it would take 2 cranks to get it started followed by random misfires. Seen a video of someone that had the same issue and they replaced the ECT sensor and fixed it for them, I also tried it with good results.

ECT= Engine Coolant Temperature

 

Erick did you have a code for bad ect sensor? That is a big cause for extended starts. As is low fuel pressure
Check fuel pressure with a gauge and see if pressure holds after car is shut off. It it drops then you need to find out what the problem is, most likely a bad fpr, bad fuel pump check ball or even a rusted line thats leaking.

 

how old are the spark plugs?
have you had the charged battery tested at parts store?
how did you use seafoam?