<E28> Need Diagnostic Help.. Solutions..

["Ron J" <ron@xxxxxxxxxxxxxxx>]

Ok , Thank you for everyones opinions and offerings of advice

So far I have been given a broad list of possibilities, ranging from bad
connections to a bad ECU.

What I am going to do is start at the cheapest route, Cleaning
contacts(dielectric grease, and contact cleaner on all the electrical
components under the hood), Then I will check for vacuum leaks, since this
seems to be a possibility that is pretty sensible, then I will change the
main relay, change the fuel filter (which one?  There seems to be one under
the hood just before the FPR, and apparently one under the chassis
somewhere.

The only issue is that I live in Toronto Canada, and we just recieved a
dumping of over 1 foot of snow, and working outside in these conditions is
very undesirable.  Oh, how I wish this would have happened while I was in
Florida.  the warm weather would have made the repairs more tolerable.

Anyone with some warm working space up here?

Cheers
Ron J
- ----- Original Message -----
From: "Shaun Dustin" <sdustin@domain.elided>
To: <bmw@domain.elided>; <ron@domain.elided>
Sent: Monday, January 06, 2003 10:40 AM
Subject: RE:<E28> Need Diagnostic Help.. 535i running rough


> Ron,
>
> Sounds suspiciously like maybe a fuel filter (best case), or a fuel pump,
> but I would be inclined to replace the filter first. A crapped up fuel
> filter will do what you describe, and although I'm not familiar with the
> e-28 per se, I've felt similar symptoms in old VWs, pickups, and my '91
> e-30. Comes from bad gas (we get a lot of that in rural Idaho), running
your
> tank too low (fillup will suspend sediment on the bottom of the tank),
etc.
> Unless someone else comes up with a better answer, I'd replace it and see
> what happens. A bad filter will stress your fuel pump by raising system
> pressure between the filter and the pump, and accelerate wear on the pump.
> It can also cause your engine to run lean, unless BMWs have electronices
to
> prevent that???. On old VWs, it usually ends up meaning a burnt valve in
my
> experience.
>
>
> Shaun Dustin, PE
> Intrepid Technology and Resources
> 501 West Broadway
> Ste 200
> Idaho Falls, ID 83402
> 208-529-5337
> www.intrepid21.com
>
> Date: Sat, 4 Jan 2003 11:06:40 -0500
> From: "Ron J" <ron@domain.elided>
> Subject: <E28> Need Diagnostic Help.. 535i running rough
>
> Hi All,
>
> Well after a long drive back from Fort Myers FLA, and a good nights sleep,
I
> wanted to ask for some diagnostic help.  Here is the background.
>
> I have recently replaced my Feul Pressure Regulator with a brand new Bosch
> unit, due to rough idle, and engine missing during driving. It solved the
> problems, and the car ran much better.  I have also replaced my ICV with a
> brand new Bosch unit.  Both within the last 3 weeks.  The ICV was replaced
> on New Years Day.
>
> I drove all the way down to Florida with the new FPR (replaced before I
left
> here to go) and the car was fine all the way down except for the IVC
getting
> stuck everyonce in a while (I would pull over whenever it got stuck and
tap
> on it with a wrench and the car would stop the surging RPM and settle).
> While I was in florida, the car was fine, save the ICV issue.  We drove to
> Key West, all over the Everglades, into Fort Myers, Naples, and a few
other
> places.  No problems.  While I was there I decided to replace the ICV and
> ordered a Bosch Unit from thepartsbin.com.  It took a few days to arrive
and
> I replaced the old one with the new and the surging idle/high idle went
> away.   I thought this would have solved my problems, however it didnt.
>
> On the way back the car started to behave strangely.  It initially started
> when the car was idling.  It would stay at the normal idle speed, and then
> all of a sudden on its own surge up to 1500 rpm, and stay there steady.
If
> you tried to hit the gas the car would almost stall out.  Then the RPM
would
> settle down and the car would be fine.  Then in Kentucky I pulled into a
> subway to grab a snack for our 6 year old passenger.  When we got back
out,
> the car wouldn't start, like it was out of gas, even though we had a full
> tank.  I continued to turn the engine over and the car finally started up,
> and we drove away.  Then while on the highway in 5th gear running at about
> 2000-3000 rpm doing about 70 mph, the car would start to stumble, like it
> was either losing spark or running out of gas, and then catch again.  I
also
> noticed the fuel consumption guage start to act strangely.  Just before
the
> car would start to act strangely, the feul consumption guage would start
to
> climb up really high.  (The car has metric guages so its measured in
> litres/100kms.  1 gallon is approx 3.8 litres, and 1 km is approx 0.6
> miles. ) the guage would swing from a normal 9 ltrs/100kms to over 25/100,
> and then the car would stumble.  This makes me think that the car is being
> fed too much gas.  I dont know how that guage works, or what it measures
for
> its calculation.  But its saying that the feul consumption is way off the
> chart whenever the stumbling starts.    The car would do this
intermittently
> all the way back to Toronto Canada.  Sometimes it would do this steadily
for
> 10 min and the sometimes only 1 or two times in 20 min.  It wasnt
> consistent, and the only precursor was the feul consumption guage.
>
> Whenever we stopped I left the car running since I didnt want to have the
> issue of a non start.  While it would sit there, the idle would be fine
and
> then jump up all on its own to 1500-2000 rpm and again if you hit the gas
it
> would almost stall out, unless you quickly let off.
>
> this happened to me once before and it was recommended that it was my FPR,
> so I have a new one, so I dont think its the FPR.  The stumbling during
> driving is hard on the entire drive train since its jerky and immediate
loss
> of power and then just as immediate return, and sometimes its on and off a
> few times in a few seconds, which resembles a jack rabbit start when
someone
> doesnt know how to drive standard.  So I know there is stress on the
crank,
> transmission, driveshaft, and rear end, among other things.
>
> Is there anyone that can suggest a solution or offer any advice?
>
> Cheers
> Ron Jordan
> 85 535i
> 73 911s 2.7
>
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> End of bmw-digest V9 #2329
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