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Question for SigForum Mechanics or those so inclined: Fuel Injection

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https://sigforum.com/eve/forums/a/tpc/f/320601935/m/2120099905

July 28, 2024, 01:47 PM
smschulz
Question for SigForum Mechanics or those so inclined: Fuel Injection
So my 20 year old Nissan Titan 's starter is going out and in the ultimate design they put the starter in the middle of the engine under the intake manifold. Frown

OK moving past that ~ so I have the intake manifold off and it has the fuel rail attached.
Since everything is off I decided to pull the injectors and clean.
I cleaned them ultrasonically then I used my power probe to verify function, spray pattern with injector cleaner.
I replaced the o rings and reassembled to the intake manifold.

Question: Do I need to prime the rail?

If so ~ just injecting some gas into the rail first?

or will it prime itself ~ I might have read that to just turn the key on first for a short time might prime it?


Any insight or no big deal anyway?

thanks
July 28, 2024, 01:51 PM
egregore
It will prime itself. It might take ~2-5 extra seconds of cranking the first time.
July 28, 2024, 01:52 PM
83v45magna
I would think it should just pump up to the injectors, either once the key is turned (when you hear the pump running), or upon a little crank time. Once the line pressure threshold is reached, it'll start up.

I would just cycle the key on (not to start) for about 5-10 seconds, maybe twice till you don't hear the pump. Then likely it will light right off.
July 28, 2024, 01:55 PM
sigmonkey
Most FI have return line and "purge" with key on and/or sensors that will not let the ignition fire until it is stable.

Do "key on" for 90 seconds, then "key off" then Key on" for 90 seconds, then "Key Off" then start it.

It might shudder and stumble for a few seconds, then stablize.




"the meaning of life, is to give life meaning" Ani Yehudi אני יהודי Le'olam lo shuv לעולם לא שוב!
July 28, 2024, 03:20 PM
smschulz
Thanks, guys. Cool
July 28, 2024, 04:07 PM
comet24
Turn the key to the on position. You should hear the fuel pump kick on for a few seconds. When it stops I would repeat the process a few times and then start it up.


_____________________________________

Because in the end, you won’t remember the time you spent working in the office or mowing your lawn. Climb that goddamn mountain. Jack Kerouac
July 29, 2024, 01:29 PM
c1steve
Since it has a rail, it needs no priming. Older diesels w/o a rail needed priming, except the VW diesel that was self priming.


-c1steve
July 29, 2024, 02:42 PM
egregore
On the Titan starters I have done, there was no problem with restarting. However, I did not completely empty the fuel rail or disassemble the injectors.
July 30, 2024, 09:42 AM
smschulz
quote:
Originally posted by egregore:
On the Titan starters I have done, there was no problem with restarting. However, I did not completely empty the fuel rail or disassemble the injectors.



I know, I didn't have to but at 20 years old I thought I'd clean and check the function since the intake was off.
I did have one that was a little slow but cleaned up nicely.