I'll make this short and sweet cuz I hate reading a life story when trying to help others:
Just the facts-

2000 TL, 245,000 miles.
Newish engine (105k miles), new starter, new battery, new (rebuilt) AV6 tranny, alternator (93k), new crank position sensor, new timing belt & misc, everything working great! Runs fabulous for months!

Last thing I need to do is replace the 250k fuel pump in the tank.
(Perfect example of "if it aint broke, don't fix it").

Swap in a new NAPA fuel pump (not the assembly, just the pump and parts). Car runs great that night. Out late that night revving the engine high-ish for 20 mins to make sure fuel pump works. No problems.
Next day? Doesn't start. At all.

WTF?

Mess around for weeks - check 15A fuel pump fuse (good), replace main fuel relay under dash.
No change. Still doesn't start.

Remove NAPA fuel pump and replace with original.
No change. Still doesn't start.

Remove input snorkel, spray starting fluid in intake - it starts (rough), but runs perfectly once started.
Let run for 20 minutes - no problem
Turn off then immediately try to restart? No start.

Remove throttle body & intake manifold cover (it's all clean) spray the crap outta it with carb cleaner everywhere.
Replace. Key dance to prime fuel pressure. Crank, crank, crank, No start.

Remove fuel inlet banjo connection - no fuel pressure spray (??) It should spray some fuel out, right?
Replace fuel pressure regulator. 10-cycle "key dance" to re-prime fuel pressure. No start.

Spray starting fluid in intake - starts and runs (very rough idle at first, but then eventually runs great).
Shut off and IMMEDIATELY try to restart? No start.

The fuel pump is priming correctly (verified by audio & watching it pump gas into a cup in engine bay).
The fuel pump is obviously delivering fuel correctly because the engine will run forever once it's started.

I don't know enough about the "starting circuit" of an Acura TL to know what to try next. I don't have a fuel pressure gauge, but am borrowing one soon. I suspect it's not really going to help much.

Leaking injector(s) flooding the engine?
BTW - there's ZERO codes reported.

The "fuel pump prime" key dance doesn't seem to do much - every now and then it will fire, but not start. If I keep trying (like 15 minutes) if will eventually "start", but barely, like 300 rpm, on the verge of dying. Then it will die. Then no start.

The only thing that gets it started is spraying starting fluid into the intake. Then it will sputter then start then run fine.

I'm out of ideas here.
Any suggestions would be greatly appreciated.
Thank-you!
--Randy

 

Did you replace the fuel filter in addition to the pump? Additionally, I know you mentioned fuel was coming out into a cup, but perhaps the pressure isn't correct (the filter would impact this too).

 

I know you said you replaced the starter, but maybe you got a bad new one?? Or does the engine turn but not start?

 

another simple thing to check would be the battery connection. also, helpful to note if hard to start when cold, hot or just all the time.

 

Battery is fine - it cranks with no problem.
I had heard there is no fuel filter, except in the tank (which is more like a pickup screen), and yes that was replaced with the new fuel pump.

I read somewhere the fuel filter is "built in" to the fuel pump assembly (not the motor, but the apparatus which houses the motor). If true, that is definitely a possibility. I had also heard one instance of the resistance of the fuel tank pump assembly becoming "too high" and therefore not providing enough fuel pressure. Obviously when I pumped the fuel into a cup there was no pressure generated. This is something I'm going to dig into next also.

Now that I have a fuel pressure kit, I'm going to dive into both of these shortly.

Thanks for the suggestions!

 

Ya - brand new starter from NAPA. It cranks just fine, just doesn't fire without a LOT of work (priming the fuel pump a dozen times and/or using starter fluid)

 

Yep, borrow that fuel pressure gauge.

Once it's running, what are the fuel trims?

 

Just to close this out -
It was the fuel pump assembly (not the fuel pump motor itself, as I had replaced that earlier).

I realized it was $35 to buy the Acura fuel pressure tester adapter (which I needed just to connect a fuel pressure gauge for testing), or $60 to replace the whole shebang - assembly, motor, etc.
I took a chance and bought the entire fuel pump assembly (not just the replacement motor, but the entire assembly that drops into the tank, which includes the "non-replaceable" fuel filter). So I never actually connected a fuel pressure gauge, since I never bought the special "Acura adapter".

An hour or so later after installing all of it - it was firing up and running perfectly.
Apparently my OEM fuel pump assembly wasn't delivering enough startup pressure/voltage/something even AFTER I replaced the pump motor within that assembly. (Maybe the culprit was the "built-in" "life-long" filter encased in that assembly? Or some connection on that assembly was perturbed enough that it didn't deliver enough startup pressure?)

Anyhew - thanks GREATLY to all of you who read through all this and made suggestions....
Those of us keeping our 2G TLs running love you guys!
--Randy

 

Appreciate closing this out! I bought all those diagnostic parts in the off chance that my fuel filter wasn't the root cause and ended up never needing them.

I suppose the tricky thing with fuel pressure in our cars is that it's not monitored the way other parts of the system are and so when things start acting up without throwing codes, it becomes a little more challenging to figure out.