Hurray, my car threw codes!! P1128 and P1130. But I replaced MAF and no different, ideas...
04-06-2007, 08:05 AM
#11
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How would I measure flow w/o the VAG tool Bentley says I need. It's something you plug into fuse ..
box at #28 I think (fuel pump). The you hook one end to + battery terminal (IIRC) and then turn on for 15 seconds. But I don't have that tool. Is there another way to rig it to turn on pump? BTW, thanks for all these great suggestions!!!
04-06-2007, 08:19 AM
#12
I took a look at Bentley, you can get by without the tool if you have a helper
The tool has a remote switch to make it easier for one person to perform, but that's all it really does.
Just get a piece of wire that's long enough to go from the battery + terminal to the right side of the fuel pump fuse. Attach one end to the battery terminal (just strip it and twist it around the terminal a few times). With the fuse removed, it should be possible to push the other end of the wire into the slot where the right fuse blade goes.
I take it you have the Bentley manual and the flow rate chart?
Just get a piece of wire that's long enough to go from the battery + terminal to the right side of the fuel pump fuse. Attach one end to the battery terminal (just strip it and twist it around the terminal a few times). With the fuse removed, it should be possible to push the other end of the wire into the slot where the right fuse blade goes.
I take it you have the Bentley manual and the flow rate chart?
04-06-2007, 08:33 AM
#13
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Thanks! Yes, I have Bentley. Looks like .4 liter in 15 seconds? And thanks for the tip about the
wire. I knew it couldn't be too hard to rig up but wasn't sure which side of fuse to put wire on. Thanks! Any other ideas if that turns out normal?
04-06-2007, 11:57 AM
#16
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Which is the fuel return line? The screwed on one or the clamped one? Bentley shows..
that is the screwed on connection. Maybe I'm wrong, but wouldn't you want to check fuel flow before it gets to the fpr and injectors? Or do I have that reversed? So, which line do I pull off to check flow: the screwed on one or the clamped on one? I have the 2.8 30v.
BTW, I did pull off vacuum line to fpr and sealed vacuum line and it made no change in how engine runs. FYI, I can rev it up a bit with some effort (will stumble if I floor it, but if I massage throttle it will rev up) but only in park or neutral. Put any kind of load on engine, like in gear, and will just stumble. This happens regardless of vacuum attached to fpr or not.
BTW, I did pull off vacuum line to fpr and sealed vacuum line and it made no change in how engine runs. FYI, I can rev it up a bit with some effort (will stumble if I floor it, but if I massage throttle it will rev up) but only in park or neutral. Put any kind of load on engine, like in gear, and will just stumble. This happens regardless of vacuum attached to fpr or not.
04-06-2007, 12:12 PM
#17
Looks like the return line is the one with the clamp (one of the Bentley pics clearly shows it)
I does make sense to check the return line because that shows how much flow is available at the required rail pressure. The supply line might have a lot of flow with the hose disconnected, but the flow might drop dramatically under pressure.
It looks like the return line will be easier to test with anyway, just need to get a similarly sized hose and slide it onto the metal fitting.
It looks like the return line will be easier to test with anyway, just need to get a similarly sized hose and slide it onto the metal fitting.
04-06-2007, 12:12 PM
#18
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My bad. Bentley has return as clamped on line as best as I can tell. However,
wouldn't you want to check flow before fpr and imjectors as I mentioned in my post above?
04-06-2007, 02:34 PM
#19
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That's my plan. I'm not sure if I'm hoping for low flow or not. Replacing the fuel line..
assuming it has an obstruction can't be easy or cheap I imagine. But since I'm getting lean condition (p1128 and p1130) on both cylinder banks, it is most likely something that is affecting flow to both banks. MAF was not the problem (replaced). Only things I can think of are fuel pump (replaced), fuel filter (replaced, but problem happened right after that), or obstructed fuel line.
04-07-2007, 10:52 AM
#20
Should be able to clear the line if it's obstructed
With the fuel filter removed, you could blast compressed air back through the line from the supply-side (screw) fitting by the engine. That should blast out any crap in there.