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Bosh 044 problems


mplavery

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I just installed Robs Bosh 044 fuel pump which I bought of him to replace my Walbro pump... Rob supplied it to me with all the hanger etc so it was just a plug n play job which we both thought

 

However I seem to be having problems

 

When I first started the car it run then cut out within a second which was to be expected

 

After a few goes it seemed to be running fine ... Let it run for about 5 min then put it in the garage

 

Was going to give the car a run today and it's doing the same when I first installed the pump

 

It runs for 30sec then stalls ... Then will take a few turns of the key then it will start ... Leave it on idle then after 30 seconds stall again

 

 

Any ideas ?

 

Is the pump shorting out a relay possibly ? Are there any mods I need to have to run this pump

 

My current set up is full BPU

 

cheers guys n gals

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http://mkivsupra.net/vbb/showthread.php?272568-can-a-stock-fuel-ecu-run-a-400lph-pump-okay&highlight=fuel+pumps above its the fuel pump ecu I had the exact same thing with my walbro 400, I fitted a relay ,

Do the fuel pump test in the diagnoistic port

B+ and fp (double check that first though) put a shot in and it will give your pump the 12v its needs

Edited by mellonman (see edit history)
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Wiring damaged? Connection loose? Wiring in the car overheating? Fuel Pump ECU not man enough for the current draw of the 044?

 

I would go with wiring or fuel pump ecu!

 

1st step IMO would be bypass fuel pump ECU to dry it and check all the wiring and earths. Maybe a relay issue?

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The stock connector plug and socket is nothing like up to running the current demands of an 044. Two 044's usually get the pins so hot the plastic of the shells melts. It could also be an ECU / sensor thing, if it's mapped to only run the pumps with oil pressure showing, after a few seconds of cranking. But that connector for the top of the tank is not up to it....

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But did you do the fuel pump ecu bypass to test its not that, its common for the ecu to not have enough power when its at the 9v power

Like I said all you had to do is put a shorting wire in the engine diagnostic point fp to b+

Could of saved you alot of work

 

 

Going to look into it bud for sure, I just had to get it back in the road as I'm doing Santapod on Sunday .... I have already checked out your linky , thanks for that :D

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It looks like the one way anti drain back valve is missing off the 044, too. I have a car here like that. The fuel rail pressure disappears as soon as the pump stops running. It *SHOULD* retain rail pressure for hours. Quite why people take them off I don't know, maybe because they try to squeeze them into the original hanger and it's too long with it in place? They come as stock on genuine Bosch pumps. Removing them is BAD practice though, causes vapour locks and potentially bad hot or cold starting issues. People can't remove them from a stock pump as they are internal.

Edited by Chris Wilson (see edit history)
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From my experience with 044's any pump that can draw 18amps @ 6 bar is going to require some vastly upgraded wiring with a 40amp fused relay to switch the pump (I kid you not, 30amp fuses just melt). I would pass the 044 pump on and run a Walbro 450 turbine pump. It is supposedly rated to 800 - 1000bhp (although I have serious doubts about that claim). Even so the flow graph is better in parts than a 044 (until we get up to the dizzy heights of 5.5 bar) and consumes much less current.

 

http://www.glencoeltd.co.uk/walbro-fuel-pumps-hi-fuel-pumps-in-tank/walbro-fuel-pumps/walbro-450-lph-competition-in-tank-fuel-pump-kit-f90000267/

 

There was a handy pump comparison on supra forums web site.

 

http://www.supraforums.com/forum/showthread.php?683983-Fuel-Pump-Comparison-Bosch-044-vs.-Walbro-416lph-vs.-Walbro-255lph-vs.-Supra-Denso

 

Lyndon.

Edited by Nodalmighty (see edit history)
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