[raymacke]

I recently acquired a 2005 AN400 with 5000 miles on it. Ran fine about a year ago but the previous owner let it set. Pumped out the fuel and added fresh. It will start easily and idle for 20 seconds or so then miss once, run a few more seconds and die. After10 seconds or so it will start again and repeat the process. I can rev the engine for about 20 to 30 seconds but then it again dies. I checked spark and it's OK. To me, it seems like a fuel issue. What I have done so far -

Checked the injector - Ohms reading OK at 11.4 Applied 9v to injector - it appears to pump fine as I can feel air movement out the nozzle and hear/feel it run

PULLED THE TANK! Yes, I went to that extreme. Inside looks pristine. Pulled the pump/filter/gauge assembly. There is zero debris on the plastic screen - I mean clean. Applied 12v to fuel pump and it appears to run fine. I did not disassemble the unit to check the filter because the screen was so clean. Was concerned about replacing the plastic zip ties. Not sure if the hardware store variety would withstand constant submersion in gasoline.

SO now I am at a loss. Tore it completely down (not 100% sure I can get it all back again) and still have no idea what the problem is. ANY suggestions would be greatly appreciated.

 

[Bluebottle]

Pressure return on the injectors?

I’ve had pressure build up on blocked breathers do something similar (but not on the Burg)

 

[mikeyMarine]

there is a fuel flow test for the 400, where you turn it on and measure how much fuel goes to the injector in a certain amount of time, If it were me, I'd run that test and see if fuel flow stopped, was adequate or whatever, then have a refreshin beverage while I posted the results. or just have a refreshin beverage while readin this and wait for another suggestion

 

[raymacke]

Before I tore into the tank I pulled the fuel line off the injector and turned on the key. It pumped for a second or two then stopped. I tried to get a pressure reading but without the proper test adapters it is a problem. Once I saw a momentary reading of about 40 psi and another time in the 30s but trying to simply hold hoses over the end of the line was crude and ineffective. So based on the "maybe" reading I thought perhaps there was a clog that would allow it to pump for a moment and then block. That's why I decided to check the filters on the actual pump. But then again I didn't know if there was an override in the ECM that shut off the pump when it detected no/low pressure.

At any rate, I obviously misdiagnosed the situation.

 

[Dave_J]

The ECM will run the injector and the coil for a second then when it sees no run it shuts them off.

 

[raymacke]

The ECM will run the injector and the coil for a second then when it sees no run it shuts them off.

Why did I not ask here before tearing this thing down? Sometimes I swear I am my one worst enemy!

Still, I have a problem. Not sure how to proceed.

 

[mikeyMarine]

Why did I not ask here before tearing this thing down? Sometimes I swear I am my one worst enemy!

Still, I have a problem. Not sure how to proceed.

yup but you know now the ecm may be recieveing a low/ no pressure signal. now time for a refreshing beverage while you think about the next step, (which is usually a second refreshing beverage)

 

[Scos53]

What happened?

 

[Scos53]

RM?