17 replies to this topic

[cowie165]

Hey.

 

I've fitted a dw65c (9-652-1008) to my RevC RSK, and changed the fuel filter at the same time.

 

On reassembly, I reconnected the fuel pump relay next to the driver's fuse box, reconnected the battery, and the pump primes nicely. Primed about five times then started. Engine started perfectly. But, it runs for about 30sec (ish, haven't timed it) then rpm wanders and engine stalls shortly after.

 

I thought the sock might not have been installed properly and could have been pressing up against the bottom of the tank. Removed the whole lot again, refitted the sock all the way to the base, checked the pump was seated properly, and reinstalled.

 

Same problem. Just started the engine again - car runs fine when the pump runs, but it's the pump that stops around 30sec and stalls the engine.

 

Does the ECU need to relearn something for the faster pump? Have I busted the pump controller somehow?

 

Any pointers would be solid gold. Thanks guys.

Mark

[cowie165]

Just thinking things through - the fuel filter was cheap and nasty. Wesfil/Cooper and 0/10 would not use again. The o-ring was undersize and unusable. The filter cup fitting lugs were bent and unusable. Using the OEM cup and the new filter needed the new filter to be jammed in tight. Maybe it's just garbage and as soon as the pump comes off 100% DC the filter is restricting fuel flow enough that it starves the motor.

[CRUISN]

I installed a Wesfil filter with my DW65C over a year ago and to date still good.

 

Remove and check everything is in the right position and nothing moved upon re-installing? I know the Gen4 assembly requires the O-rings to be perfectly seated otherwise you get issues but its a different design.

[Jimbo]

Oh man that's odd. Weird about the fuel filter? Mine was perfect?

I wonder if maybe you got a dodgy one?

 

[cowie165]

Thanks blokes. You were two dudes I was really hoping to hear from.

 

I installed a Wesfil filter with my DW65C over a year ago and to date still good.

 

Remove and check everything is in the right position and nothing moved upon re-installing? I know the Gen4 assembly requires the O-rings to be perfectly seated otherwise you get issues but its a different design.

 

Thanks Mark. I'll go for the third crack and might try the used OEM filter just to try and narrow down the problem. If runs fine with the OEM again it's either a bad replacement or I didn't fit the replacement properly.

 

Oh man that's odd. Weird about the fuel filter? Mine was perfect?

I wonder if maybe you got a dodgy one?

 

 

It's weird hey. Looked nice coming out of the box but the o-ring wouldn't seat and the cup was damaged. Tried to straight but still a pain, so I just cleaned the OEM cup and reused that one. As long as it got a fresh filter I'm happy. But now...! lol

 

It's good to know both you guys found it plug and play. Hopefully just operator error and nothing has busted.

 

And pro-tip Jimbo - the reason fuel pisses out the top of the pump assy despite running the engine dry is because the filler cap wasn't opened to relieve the pressure. Ask me how I know :-) (Rushed the job second time through and missed a crucial (&messy) step!)

[Jimbo]

Did you contact the seller at all and ask wtf mate?

Did it look like it was supposed to be a "new" item?

If it's conking out, maybe its losing fuel pressure out of the cup or like you said blocking it up.

Did you remember to reattach the little spade connecter to the cup?

[duncanm]

Don't forget the fuel pump controller runs 100% for a short burst at ignition on to prime the system, then will throttle back to ~30% at idle.

 

I bet your FPC or wiring is dodgy and the pump's not getting enough voltage at idle -- the 30s is the time it takes for the initial prime pressure to bleed down

 

Check the voltage at the fuel pump terminals during startup and idle -- debug back from there.

 

Assuming the pump is good -- changing it probably just loosened or broke a dodgy wire or terminal.

 

I have a 65c -- no issues.

[cowie165]

Did you contact the seller at all and ask wtf mate?

Did it look like it was supposed to be a "new" item?

If it's conking out, maybe its losing fuel pressure out of the cup or like you said blocking it up.

Did you remember to reattach the little spade connecter to the cup?

 

No, haven't been in touch. Everything appeared new but the cup wasn't in plastic (not sure if it would be). For the $20 I don't think I can be stuffed with the photos, emails, potential arguments, etc. I'm fairly confident I reattached the spade connector - but will definitely check. It was a pain to get off - perhaps I damaged something at the terminal.

 

Don't forget the fuel pump controller runs 100% for a short burst at ignition on to prime the system, then will throttle back to ~30% at idle.

 

I bet your FPC or wiring is dodgy and the pump's not getting enough voltage at idle -- the 30s is the time it takes for the initial prime pressure to bleed down

 

Check the voltage at the fuel pump terminals during startup and idle -- debug back from there.

 

Assuming the pump is good -- changing it probably just loosened or broke a dodgy wire or terminal.

 

I have a 65c -- no issues.

 

Thanks duncan. When the pump drops back to 30% and the motor starts to struggle, the system voltage drops from 14.3 down to low 13s maybe 12s for a half second or so. I don't know if that's a cause or an effect though. That's voltage at the battery though. I'm happy the pump is good.

 

Narrowing it down now to the filter being seated correctly, and checking the cup terminal/connector hasn't been damaged. For now I'm going to assume the pump controller is fine until I have a solid look at the pump assy.

 

You guys rock, thanks.

[duncanm]

Thanks duncan. When the pump drops back to 30% and the motor starts to struggle, the system voltage drops from 14.3 down to low 13s maybe 12s for a half second or so. I don't know if that's a cause or an effect though. That's voltage at the battery though. I'm happy the pump is good.

Ok - but what's the control voltage at the pump at 30%? Should be something like 5-6V, I think.

[Lukeoly]

Is it possible that your o-ring was damaged (or even dropped out) when you re-installed your new filter?

[CRUISN]

Yes, as I mentioned earlier, check that filter O - ring. If its not sealed you will have issues.

[RX25SE]

I have used Cooper filters, same deal, use the element and junk the cap and o ring.
Never had an issue.

The fuel pump controller should (almost all do) be Pulse Width Modulating either the supply or ground side if the pump to control current to pump, lower voltage is the side effect of reducing the duty cycle of a fixed frequency.
Imagine you are flicking a switch at a constant rate, if you leave it on for longer and off for shorter you get more current.
When the module commands 100%, the transistor switch in the module is held on, when less than 100% is commanded the switch cycles (GM run at 25kHz or 25000 times a second).
The controller may be missing a 'run' signal. The transistor is probably OK (unless it uses a bypass relay) as it can prime but may not be PWMing.

If your multimeter can measure Frequency (Hz) or Duty Cycle (%) then you can check it.

[cowie165]

 alive.jpg   74.67KB   3 downloads

 

And the winner is... fuel filter o-ring!

 

Ok I tried something different. I grabbed the undersized Wesfil o-ring. Mr Subaru says the o-ring is to be fitted to the cup and then both reattached to the fuel assembly. I was reusing the old o-ring because the new one wouldn't sit in the cup properly.

 

I changed it up (third time!) and fitted the new o-ring to the fuel assy. Greased it and then refit the filter cup. The cup went on quite smoothly. It's not what the FSM says but gave it a go. Fitted, started, and the motor is happy. Mark and Luke nailed it. Clearly the o-ring seal makes a big difference. Back to installing interior and audio!

 

Gents thanks for your help.

 

 image.jpg   23.73KB   2 downloads

[cowie165]

I have used Cooper filters, same deal, use the element and junk the cap and o ring.
Never had an issue.

The fuel pump controller should (almost all do) be Pulse Width Modulating either the supply or ground side if the pump to control current to pump, lower voltage is the side effect of reducing the duty cycle of a fixed frequency.
Imagine you are flicking a switch at a constant rate, if you leave it on for longer and off for shorter you get more current.
When the module commands 100%, the transistor switch in the module is held on, when less than 100% is commanded the switch cycles (GM run at 25kHz or 25000 times a second).
The controller may be missing a 'run' signal. The transistor is probably OK (unless it uses a bypass relay) as it can prime but may not be PWMing.

If your multimeter can measure Frequency (Hz) or Duty Cycle (%) then you can check it.

 

Dude, you know your stuff!

[Jimbo]

Nerds

Good to have a win!

[cowie165]

Absolutely! I was hoping it was something simple like that. But, it takes smart people to get you to check what you've done and narrow down the search a little.

[Lukeoly]

Yay! What's my prize? 

I bet you never want to see the inside of the tank again lol.

I decided to switch to the engine bay fuel filter when I swapped in my 65c so I didn't have get into the tank to do filter changes.

 

Glad to see it was something simple and didn't lead to any damage :-)

[cowie165]

Yay! What's my prize? 

I bet you never want to see the inside of the tank again lol.

I decided to switch to the engine bay fuel filter when I swapped in my 65c so I didn't have get into the tank to do filter changes.

 

Glad to see it was something simple and didn't lead to any damage :-)

 

A crisp high-five next HVC? :-D

 

Yeah, three times taking it out, including one time forgetting to ease the fuel px (filler cap!) and having to mop gas off the car and floor = sucks bro.

 

I'm glad too. I figured it was a stupid error of mine and I'm grateful for the steer towards the o-ring. Highly likely I wouldn't have swapped it out otherwise. Cheers Luke!