Weird problem....
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Weird problem....
Well, this isn't specifically an Audi question, it's about my VW Scirocco. But since nobody else can seem to help me, I thought I'd tap you guys and see what I can see.
My in-tank fuel pump went bad on me, so I replaced it today. now, it's getting fuel everywhere but through the injectors(the 'rocco is standard CIS, not CIS-E, for those keeping score). There's fuel running to the injector lines, it's just that the injectors aren't squirting. None of them. Not a drop. Not even a little bit. Bone dry. I think you get the idea. Any advice from a CIS expert would be greatly appreciated, not even the Bently manual on Bosch injection is being much help. It strikes me as bad pressure, but if anyone's seen this before, any and all help is greatly appreciated.
My in-tank fuel pump went bad on me, so I replaced it today. now, it's getting fuel everywhere but through the injectors(the 'rocco is standard CIS, not CIS-E, for those keeping score). There's fuel running to the injector lines, it's just that the injectors aren't squirting. None of them. Not a drop. Not even a little bit. Bone dry. I think you get the idea. Any advice from a CIS expert would be greatly appreciated, not even the Bently manual on Bosch injection is being much help. It strikes me as bad pressure, but if anyone's seen this before, any and all help is greatly appreciated.
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So, you checked after the pressure regulator, etc..The flow just stops at the injectors.
I haven't looked at any of this for years and years, cold start injector squirting at all? (If there even is one on your car.)
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Two Thoughts
I had an '88 80 that was causing crazy seemingly fuel filter related problems. There was an extra in-line fuel filter actually in one of the couplings, was a pain to find. If you are getting any flow when the injectors are not connected then this is probably not your problem.
Second: I am not familiar with your fuel injection system, but are the injectors themselves turned on and off? I know on my car, the amount of fuel injected is controlled by how long the injectors are kept open. Maybe your injectors are not opening.
Hope this helps,
Dave
Second: I am not familiar with your fuel injection system, but are the injectors themselves turned on and off? I know on my car, the amount of fuel injected is controlled by how long the injectors are kept open. Maybe your injectors are not opening.
Hope this helps,
Dave
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Re: Weird problem....
Check the fuel distributor plunger. Reach inside
the airbox and lift the air flap - you should
feel the resistance - fuel pressure above the
plunger. If no resistance, bypass the fuel pump
relay, so you can hear the fuel pump running. Now
lift the air flap again. You should hear the
injectors spraying the fuel. If not, check, how
far towards the engine your fuel press. goes.
With fuel pump relay bypassed (pump running)
check line connections one-by one, how far is
the pressure. I hope you wil drive soon.
the airbox and lift the air flap - you should
feel the resistance - fuel pressure above the
plunger. If no resistance, bypass the fuel pump
relay, so you can hear the fuel pump running. Now
lift the air flap again. You should hear the
injectors spraying the fuel. If not, check, how
far towards the engine your fuel press. goes.
With fuel pump relay bypassed (pump running)
check line connections one-by one, how far is
the pressure. I hope you wil drive soon.
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Re: So, you checked after the pressure regulator, etc..The flow just stops at the injectors.
Are the Injectors getting a signal to open?
Maybe there is a fuse to protect the injectors from burning out if there is no fuel.
Good Luck
Sam,
Maybe there is a fuse to protect the injectors from burning out if there is no fuel.
Good Luck
Sam,
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Injectors won't squirt unless you move the air flow meter plate up.
If your looking for fuel flow at the injector lines on the fuel distb, the air flow plate has to be moved off the rest position, otherwise there will be no flow to the lines. If you do this and see fuel flow at the distb, the next check would be at the injector. As far as I know, if you have no flow at the injector, you don't have enough pressure.
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Re: Injectors won't squirt unless you move the air flow meter plate up.
I've already checked all of this. Airflow plate moves fine, and fuel is getting everywhere it needs to go, except through the injector. The cold start valve squirts fine, nothing binds, the plunger is ok, and when I cracked the banjo bolts on the injector lines at the fuel distributor, fuel leaked out, which increased when I moved the sensor plate. By all reasoning, they should be working. CIS injcetors usually spray a little something even if they are clogged. Besides, it's odd that all four of them would be doing the same exact thing. I'm totally baffled.
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I'll talk to some friends later today. Have you measured the fuel pressure?
That's about all I can think of right now, pump maybe being weak and not generating enough pressure to activate the injectors.
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That's what I'm almost certain it is, now that I think about it.
I'm pretty sure that the bad transfer pump in the tank caused the external pump to overwork and burn out...it's not making any noise, now that I've eliminated everything else and actually listened for it. It's under warranty, so I'll give that a go. Thanks for all the suggestions, it was a big help!