[V8] Timing belt change - Fuel pump?

Ed Kellock ekellock at gmail.com
Wed Oct 3 16:26:17 PDT 2012 

The fuel pump is indeed in the tank.  The fuel filter is under the car back
by the right rear wheel.  The lovely round thing near the MAF is the fuel
pressure regulator, also something that might be at fault, though I don't
specifically recall the behavior you described.  You might also swap the MAF
for a known good one.  Both MAF and fpr are not readily available or
inexpensive to obtain new.

Ed
 


-----Original Message-----
From: v8-bounces at audifans.com [mailto:v8-bounces at audifans.com] On Behalf Of
John Bysinger
Sent: Wednesday, October 03, 2012 2:39 PM
To: v8 at audifans.com
Subject: Re: [V8] Timing belt change - Fuel pump?


Follow up after trying a few more things...

So I sourced a Siemens Hall sensor from a guy on audifans boards, rebuilt
the passenger dizzy with the new sensor, with no real change to behavior.
Replaced the drivers side knock sensor (since I had previously only repaired
the sheathing on the wire), again no change.  Capt Ron suggested a possible
cat problem, but doing the knock test nothing sounds like it's floating
around in there.  So I'm starting to wonder if the cut-out behavior is fuel
delivery related.  So that's going to be my next line of investigation.

So on to the questions, fuel pump and fuel filter, where are they located?
I assume the pump is in-tank, and the filter is the lovely round thing next
to the MAF on the fuel rail.  If there's a fuel delivery problem are there
specific codes related to that?  I'm going to track down a fuel pressure
gauge and see if I can validate this theory, any other tips/tricks?

As always, thanks in advance! :)

-John
'90V8Q

On Sat, Sep 15, 2012 at 5:16 PM, John Bysinger <doog at bysinger.net> wrote:

> Well the wires check out for continuity, and don't seem to be shorting 
> anywhere.  I'm going to re-wrap it and run it inside some wire loom 
> that I've got.  But, disconnected or connected the engine behavior 
> doesn't change.  I think my  problem lies elsewhere.
>
>
> On Sat, Sep 15, 2012 at 4:01 PM, Allan Vega <allanvega at comcast.net> 
> wrote:
>
>> That's the knock sensor that Scott mentioned in his last email to 
>> you.
>>
>> FYI , that sensor has a torque spec of 11-18ft lbs, certainly not 
>> enough to crack the housing Allan
>>
>> Sent from my iPhone
>>
>> On Sep 15, 2012, at 6:44 PM, John Bysinger <doog at bysinger.net> wrote:
>>
>> > What sensor is underneath the drivers side header?  orange plug 
>> > under
>> the
>> > engine cover on the right side of the intake, routed by the front 
>> > and timing belt cover and near the power steering pump?  The cable 
>> > to that
>> one,
>> > rubber wire coating is completely disintegrated and the plastic 
>> > casing around the sensor is crumbing.
>> >
>> > -John
>> >
>> > On Fri, Sep 14, 2012 at 9:23 PM, Scott Justusson <qshipq at aol.com>
>> wrote:
>> >
>> >> The problem with rpm codes, is they can be triggered *from* the 
>> >> intermittent stalling, not the cause of it.  Some have been known 
>> >> to
>> put
>> >> some cold water on those sensors to see if anything changes.  This
>> sounds
>> >> like a MAF symptom to me, are you sure that connector is secure?
>>  Another
>> >> issue I've seen with the older v8's is an intermittent grounded 
>> >> knock sensor causing a full max retard of the timing tables.  That 
>> >> DS one
>> goes
>> >> into a bracket on the side of the valve cover, and I've seen many 
>> >> that
>> were
>> >> grounded against the headers. Also, take a look at night, arcing 
>> >> wires
>> and
>> >> cracked distributor caps many times can send you down much more
>> complicated
>> >> paths than necessary.
>> >>
>> >> HTH
>> >>
>> >> Scott J
>> >> 91 v8 Auto 3.6
>> >> 92 v8 Auto 4.2 ABT Chipped
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> -----Original Message-----
>> >> From: John Bysinger <doog at bysinger.net>
>> >> To: V8 <v8 at audifans.com>
>> >> Sent: Fri, Sep 14, 2012 10:46 pm
>> >> Subject: Re: [V8] Timing belt change - follow up
>> >>
>> >> Ok, after some help from fellow listers, I was able to rebuild the 
>> >> passenger side distributor.  I completely re-wired the connector 
>> >> to the hall sensor, and was able to bench test it with a DC 4.5V 
>> >> source.  I thought I may have assembled the ring on the cam side 
>> >> incorrectly, but again, thanks to you guys I was able to confirm I 
>> >> got that ring in
>> properly.
>> >>
>> >> But it's still throwing a 2111 and stumbling over ~2500 RPMs in
>> neutral,
>> >> and completely gutless and stalling when in gear.  Just to 
>> >> confirm, I
>> did
>> >> as SJM's ECU page said and reset the memory by pulling the 
>> >> appropriate fuse, and trying again, same code.  I pulled the 
>> >> drivers side cover on
>> the
>> >> timing belt to see if there was any odd movement going on w/ the 
>> >> tensioner/dampener when it got to those RPMs.  No odd movement 
>> >> there either.  According to the SJM site 2111 indicates an RPM 
>> >> sensor
>> failure,
>> >> but I just replaced both of the sensors under the driver's dizzy
>> earlier
>> >> this year, barely 500 miles ago.  I rechecked their harness plugs, 
>> >> both were secure.  I also inspected the connectors, wiring and 
>> >> hoses that
>> run on
>> >> top of the engine, no real visible issues that I can tell 
>> >> visually.
>> >>
>> >> I'm really at a loss as to where to look next.  I have time this
>> weekend to
>> >> tinker with it, I'm hoping I can get it figured out before the 
>> >> Seattle
>> fall
>> >> rain gets here.
>> >>
>> >> Any tips/suggestions at this point would be very helpful.  I do 
>> >> have
>> 'an
>> >> audi guy' who has a shop 15 miles from here I could take it to, 
>> >> but
>> right
>> >> now driving it isn't possible with the stumbling, I'm trying to 
>> >> avoid
>> the
>> >> cost of getting it there if I can.  I blew my Audi budget on the 
>> >> timing belt and PS hoses.
>> >>
>> >> -John
>> >> '90 V8Q
>> >>
>> >> On Thu, Aug 16, 2012 at 8:42 PM, John Bysinger <doog at bysinger.net>
>> wrote:
>> >>
>> >>> Well I got the timing belt completed, thanks for the 
>> >>> recommendation
>> to use
>> >>> BlauParts, their kit and tool rental made it nearly a breeze.  
>> >>> The
>> kit was
>> >>> amazingly complete with seals, pulleys, fluids etc.  I also 
>> >>> replaced
>> the
>> >>> fan and oil pump bearings, because like everyone else said, I was 
>> >>> in
>> there,
>> >>> might as well.
>> >>>
>> >>> I used this for reference while I was doing the work, proved very
>> helpful:
>> >>>
>> >>>
>> http://www.audipages.com/Tech_Articles/enginemechanical/A8timingbeltr
>> eplacement.pdf
>> >>>
>> >>> It was nearly the same, just different Dizzy setup on the back of 
>> >>> the heads.
>> >>>
>> >>> I also got my leaky power steering fixed while in there, thanks 
>> >>> again spokanehose, that was the third hose I've had them done, 
>> >>> worked great.
>> >>>
>> >>> But there's always something....
>> >>>
>> >>> I ended up having to trim about 1.5" off the end of the drivers 
>> >>> side
>> of
>> >>> the top radiator hose, hose clamp pinched through it causing a 
>> >>> leak.
>>  Glad
>> >>> it was there and not elsewhere in the hose so I didn't have to
>> replace it.
>> >>> But the one remaining issue I'm having is keeping me from getting 
>> >>> it
>> back
>> >>> on the road. It's only throwing one code: 2111.  Which based on a
>> search of
>> >>> the list archives is likely the crank position sensor.  Strange.  
>> >>> I
>> just
>> >>> replaced it and it's partner about 3 months before the water pump
>> gave out,
>> >>> so I'm pretty sure the sensor is still fine.  Behavior is it 
>> >>> starts
>> and
>> >>> idles just fine, slowly increase the RPMs and around 3k it starts 
>> >>> to
>> act
>> >>> like it's skipping or stumbling.  When trying to drive, similar
>> behavior,
>> >>> idles along just fine, try to give it some throttle and it'll 
>> >>> stumble
>> and
>> >>> sometimes stall.
>> >>>
>> >>> I tried peaking under the dizzy to see if maybe the plugs had 
>> >>> come
>> loose
>> >>> while I was putting the cam lock plates on/off but they look 
>> >>> plugged
>> in ok.
>> >>> I haven't tried re-seating them just yet since there's quite a 
>> >>> bit of engine bits in the way there and I was losing sunlight.  
>> >>> Thought I
>> would
>> >>> see if anyone had any suggestions for something to check besides
>> those two
>> >>> sensors hidden behind the drivers side header.
>> >>>
>> >>> Only other noteworthy item is on the passenger dizzy there's a 
>> >>> sensor
>> that
>> >>> the plug socket had crumbled a bit, I cleaned it up and made a 
>> >>> clamp
>> of
>> >>> sorts to hold it in place, could that be my issue?
>> >>>
>> >>> -John
>> >>> john at bysinger.net
>> >>> '90 V8Q
>> >>>
>> >>
>> >>
>> >>
>> >> -- john at bysinger.net
>> >>
>> >> _______________________________________________
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>> >>
>> >>
>> >
>> >
>> > --
>> > john at bysinger.net _______________________________________________
>> > Audifans V8 mailing list
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>> > Manage your list connection:
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>> >
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>> http://audifans.com/shop/
>> >
>>
>
>
>
> --
> john at bysinger.net
>



-- 
john at bysinger.net
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