The BMW UUC Digest 
Volume 2 : Issue 729 : "text" Format

Messages in this Issue:
  different fuel
  Re: different fuel
  <E30> Engine removal
  Re: <E30> Engine removal
  New clutch problem
  Re: New clutch problem
  Re: New clutch problem
  Re: <E30> Engine removal
  Re: <E30> Engine removal
  Re: E36 325i question - OBD1 O2 sensor & MPG needle
  Re: E36 325i question - OBD1 O2 sensor & MPG needle

----------------------------------------------------------------------

Date: Sat, 9 Jul 2005 23:02:58 -0700
From: [EMAIL PROTECTED]
To: [email protected]
Subject: different fuel
Message-ID: <[EMAIL PROTECTED]>

Brett,

As Maverik indicated, or tried to, the basic problem is a cast aluminum
piston which needs to come up to temp before it stops flopping around in
the cylinder. Typically it will happen when the motor is cold and quiets
when the motor is at operating temp. When the piston(at temp) and the bore
are at opposite ends of the dimensional specs the motor (typically 5.7 and
6.0 liter) the thing sounds like a diesel and won't improve. My motor was
quiet as a church until it hit 20k miles than in the mornings it would
rattle until warm.
This same technology is common on some european cars but somehow better
engineered.

In some severe cases GM would rebuild the motors. I have joined a class
action suite on this issue.

-Kevin
 ---------------------------------------------------------------- 
 This  e-mail  communication is confidential and is intended only 
 for  the individual(s) or entity named above and others who have 
 been  specifically  authorized to receive it. If you are not the 
 intended  recipient,  please  do not read, copy, use or disclose 
 the  contents of this communication to others. Please notify the 
 sender  that  you have received this e-mail in error by replying 
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 it. Thank you.                                                   
 ---------------------------------------------------------------- 


------------------------------

Date: Sun, 10 Jul 2005 06:48:33 -0400 (GMT-04:00)
From: Maverick <[EMAIL PROTECTED]>
To: [email protected]
Subject: Re: different fuel
Message-ID: <[EMAIL PROTECTED]>

Kevin,

Where can i find further info on the class action suit?

David in Richmond, VA

-----Original Message-----
From: [EMAIL PROTECTED]
Sent: Jul 10, 2005 2:02 AM
To: [email protected]
Subject: [UUC] different fuel

Brett,

As Maverik indicated, or tried to, the basic problem is a cast aluminum
piston which needs to come up to temp before it stops flopping around in
the cylinder. Typically it will happen when the motor is cold and quiets
when the motor is at operating temp. When the piston(at temp) and the bore
are at opposite ends of the dimensional specs the motor (typically 5.7 and
6.0 liter) the thing sounds like a diesel and won't improve. My motor was
quiet as a church until it hit 20k miles than in the mornings it would
rattle until warm.
This same technology is common on some european cars but somehow better
engineered.

In some severe cases GM would rebuild the motors. I have joined a class
action suite on this issue.

-Kevin
 ---------------------------------------------------------------- 
 This  e-mail  communication is confidential and is intended only 
 for  the individual(s) or entity named above and others who have 
 been  specifically  authorized to receive it. If you are not the 
 intended  recipient,  please  do not read, copy, use or disclose 
 the  contents of this communication to others. Please notify the 
 sender  that  you have received this e-mail in error by replying 
 to  the e-mail.  Please then delete the e-mail and any copies of 
 it. Thank you.                                                   
 ---------------------------------------------------------------- 

Search the ARCHIVES:http://www.mail-archive.com/[email protected]


__________________________________________________________________________
In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.

UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
Short Shifter - accept no substitutes!
908-874-9092 . http://www.uucmotorwerks.com


------------------------------

Date: Sat, 9 Jul 2005 23:28:19 -0700
From: [EMAIL PROTECTED]
To: [email protected]
Subject: <E30> Engine removal
Message-ID: <[EMAIL PROTECTED]>

well I started the procedure to get the engine ready for extraction on the
e30 but I'm puzzled by some things in the Bentley.

1. Why does the Bentley call for removal of some of the sensor connectors
(eg. the oil pressure sensor under the oil filter) when they'll just come
with the main bus which I pulled from the ECU? Also why take off the
coolant pipe that goes along the front of the engine? I can't see a need
for it. And why remove the fuel injector, speed sensor , and purge valve
connectors?

2. If I pull the tranny and engine as a unit, why do I have to remove the
starter? I've taken the wiring off the selonoid before I realized it
probably wasn't necessary. I'll have to try to figure out where they go
back later.

3. Where's that rear pick up point for the hoist?

4. Is it better to remove the down pipes from the exhaust manifold or to
remove the manifold itself before taking out the motor?

5. Why does the oil dipstick have to be removed?

Jenny, Brett, Jack , Carlos?

Thanks, Kevin

 ---------------------------------------------------------------- 
 This  e-mail  communication is confidential and is intended only 
 for  the individual(s) or entity named above and others who have 
 been  specifically  authorized to receive it. If you are not the 
 intended  recipient,  please  do not read, copy, use or disclose 
 the  contents of this communication to others. Please notify the 
 sender  that  you have received this e-mail in error by replying 
 to  the e-mail.  Please then delete the e-mail and any copies of 
 it. Thank you.                                                   
 ---------------------------------------------------------------- 



------------------------------

Date: Sun, 10 Jul 2005 05:46:27 -0500
From: Jenny Morgan <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Cc: [email protected]
Subject: Re: <E30> Engine removal
Message-ID: <[EMAIL PROTECTED]>


On Jul 10, 2005, at 1:28 AM, [EMAIL PROTECTED] wrote:

> well I started the procedure to get the engine ready for extraction on 
> the
> e30 but I'm puzzled by some things in the Bentley.
>
> 1. Why does the Bentley call for removal of some of the sensor 
> connectors
> (eg. the oil pressure sensor under the oil filter)

This wire is usually under the A/C bracket, and to remove the wire, you 
either need to cut it, remove the connectors from the housing, or 
remove the a/c bracket from the block.

> when they'll just come
> with the main bus which I pulled from the ECU? Also why take off the
> coolant pipe that goes along the front of the engine? I can't see a 
> need
> for it. And why remove the fuel injector, speed sensor , and purge 
> valve
> connectors?

Sometimes, it makes sense to remove things to prevent damage, or the 
possiblity of damage. Sometimes not. Ya roll the dice and take yer 
chances. The Bentley book may not be current enough to recognize the 
difference in harnesses  of the early "i" to the late "i", RE: 
connector under the throttle body.

>
> 2. If I pull the tranny and engine as a unit,

Really?  Have fun. I've done it as a unit once... never again. Others 
may disagree, but I prefer separately. Then, I'll drop the tranny, 
plant the engine and mate the tranny to the new engine.

We all have different styles.

> why do I have to remove the
> starter?

Dunno, why? Maybe because it has no forward tie-down, and when you 
remove the 2 starter bolts at the bell housing, nothing is supporting 
it. You certainly don't want it to dangle from the scrawny wires.

> I've taken the wiring off the selonoid before I realized it
> probably wasn't necessary. I'll have to try to figure out where they go
> back later.

One word...  LABELS

>
> 3. Where's that rear pick up point for the hoist?

It is cast into the block... about midway R to L of the engine... just 
above the top starter bolt.

>
> 4. Is it better to remove the down pipes from the exhaust manifold or 
> to
> remove the manifold itself before taking out the motor?

I remove the down pipes.

>
> 5. Why does the oil dipstick have to be removed?

Why do you want to break off the delicate and brittle plastic top?

>
> Jenny, Brett, Jack , Carlos?
>
> Thanks, Kevin


------------------------------

Date: Sun, 10 Jul 2005 09:51:47 -0500
From: "Craig Robson" <[EMAIL PROTECTED]>
To: <[email protected]>
Subject: New clutch problem
Message-ID: <[EMAIL PROTECTED]>

All:
    I had the UUC lightweight flywheel and M5 clutch installed by a
professional on my E46 M3, but I am having some problems.

First, I am getting a lot of clutch chatter, so much that it appears to have
ruined my center support bearing (or could that have been caused by
something else like a loose bolt somewhere?). What could be causing the
chatter? The Bentley did not have the torque value for the flywheel so he
looked it up in his computer and he says it gave him two values of which he
chose the higher (90 something ft-lbs). For the bolts holding the clutch to
the flywheel, he says he did one or two ft-lbs more than factory spec, so
like 27 I think.

Second problem I am having is the transmission rattle. We replaced the fluid
with Motul 75-90 (what was handy) and it had little to no effect. Should I
try Redline MTL 90? My mechanic thinks it is the input shaft bearing on the
transmission, but I disagree. I think it is just the rattle since if I turn
the A/C off it goes to a bearable level. Should I try ordering a chip and
bumping the idle up a bit?


Craig Robson
'01 M3<-- please help me!

----- Original Message ----- 
From: <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, July 10, 2005 1:28 AM
Subject: [UUC] <E30> Engine removal


> well I started the procedure to get the engine ready for extraction on the
> e30 but I'm puzzled by some things in the Bentley.
>
> 1. Why does the Bentley call for removal of some of the sensor connectors
> (eg. the oil pressure sensor under the oil filter) when they'll just come
> with the main bus which I pulled from the ECU? Also why take off the
> coolant pipe that goes along the front of the engine? I can't see a need
> for it. And why remove the fuel injector, speed sensor , and purge valve
> connectors?
>
> 2. If I pull the tranny and engine as a unit, why do I have to remove the
> starter? I've taken the wiring off the selonoid before I realized it
> probably wasn't necessary. I'll have to try to figure out where they go
> back later.
>
> 3. Where's that rear pick up point for the hoist?
>
> 4. Is it better to remove the down pipes from the exhaust manifold or to
> remove the manifold itself before taking out the motor?
>
> 5. Why does the oil dipstick have to be removed?
>
> Jenny, Brett, Jack , Carlos?
>
> Thanks, Kevin
>
>  ---------------------------------------------------------------- 
>  This  e-mail  communication is confidential and is intended only
>  for  the individual(s) or entity named above and others who have
>  been  specifically  authorized to receive it. If you are not the
>  intended  recipient,  please  do not read, copy, use or disclose
>  the  contents of this communication to others. Please notify the
>  sender  that  you have received this e-mail in error by replying
>  to  the e-mail.  Please then delete the e-mail and any copies of
>  it. Thank you.
>  ---------------------------------------------------------------- 
>
>
> Search the ARCHIVES:http://www.mail-archive.com/[email protected]
>
>
> __________________________________________________________________________
> In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.
>
> UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
> Short Shifter - accept no substitutes!
> 908-874-9092 . http://www.uucmotorwerks.com


------------------------------

Date: Sun, 10 Jul 2005 12:09:22 -0400
From: "Gary Derian" <[EMAIL PROTECTED]>
To: "Craig Robson" <[EMAIL PROTECTED]>, <[email protected]>
Subject: Re: New clutch problem
Message-ID: <[EMAIL PROTECTED]>

By installing a lightweight flywheel, you have removed a large vibration
damper designed to stop transmission rattle when idling in neutral.
Consider it a badge of honor, not a problem.

The clutch should not chatter, though.  Generally clutch chatter is caused
by contamination.  Try slipping the clutch to heat it up and burn off the
contamination.  Don't do it too much, though.

A loose or misaligned center bearing or flex disk can cause a vibration that
seems like clutch chatter.

Gary Derian



> All:
>    I had the UUC lightweight flywheel and M5 clutch installed by a
> professional on my E46 M3, but I am having some problems.
>
> First, I am getting a lot of clutch chatter, so much that it appears to
> have
> ruined my center support bearing (or could that have been caused by
> something else like a loose bolt somewhere?). What could be causing the
> chatter? The Bentley did not have the torque value for the flywheel so he
> looked it up in his computer and he says it gave him two values of which
> he
> chose the higher (90 something ft-lbs). For the bolts holding the clutch
> to
> the flywheel, he says he did one or two ft-lbs more than factory spec, so
> like 27 I think.
>
> Second problem I am having is the transmission rattle. We replaced the
> fluid
> with Motul 75-90 (what was handy) and it had little to no effect. Should I
> try Redline MTL 90? My mechanic thinks it is the input shaft bearing on
> the
> transmission, but I disagree. I think it is just the rattle since if I
> turn
> the A/C off it goes to a bearable level. Should I try ordering a chip and
> bumping the idle up a bit?
>
>
> Craig Robson
> '01 M3<-- please help me!
>
> ----- Original Message ----- 
> From: <[EMAIL PROTECTED]>
> To: <[email protected]>
> Sent: Sunday, July 10, 2005 1:28 AM
> Subject: [UUC] <E30> Engine removal
>
>
>> well I started the procedure to get the engine ready for extraction on
>> the
>> e30 but I'm puzzled by some things in the Bentley.
>>
>> 1. Why does the Bentley call for removal of some of the sensor connectors
>> (eg. the oil pressure sensor under the oil filter) when they'll just come
>> with the main bus which I pulled from the ECU? Also why take off the
>> coolant pipe that goes along the front of the engine? I can't see a need
>> for it. And why remove the fuel injector, speed sensor , and purge valve
>> connectors?
>>
>> 2. If I pull the tranny and engine as a unit, why do I have to remove the
>> starter? I've taken the wiring off the selonoid before I realized it
>> probably wasn't necessary. I'll have to try to figure out where they go
>> back later.
>>
>> 3. Where's that rear pick up point for the hoist?
>>
>> 4. Is it better to remove the down pipes from the exhaust manifold or to
>> remove the manifold itself before taking out the motor?
>>
>> 5. Why does the oil dipstick have to be removed?
>>
>> Jenny, Brett, Jack , Carlos?
>>
>> Thanks, Kevin
>>
>>  ---------------------------------------------------------------- 
>>  This  e-mail  communication is confidential and is intended only
>>  for  the individual(s) or entity named above and others who have
>>  been  specifically  authorized to receive it. If you are not the
>>  intended  recipient,  please  do not read, copy, use or disclose
>>  the  contents of this communication to others. Please notify the
>>  sender  that  you have received this e-mail in error by replying
>>  to  the e-mail.  Please then delete the e-mail and any copies of
>>  it. Thank you.
>>  ---------------------------------------------------------------- 
>>
>>
>> Search the
>> ARCHIVES:http://www.mail-archive.com/[email protected]
>>
>>
>> __________________________________________________________________________
>> In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.
>>
>> UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
>> Short Shifter - accept no substitutes!
>> 908-874-9092 . http://www.uucmotorwerks.com
>
> Search the ARCHIVES:http://www.mail-archive.com/[email protected]
>
>
> __________________________________________________________________________
> In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.
>
> UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
> Short Shifter - accept no substitutes!
> 908-874-9092 . http://www.uucmotorwerks.com
>



------------------------------

Date: Sun, 10 Jul 2005 09:30:44 -0700
From: "Marco Romani" <[EMAIL PROTECTED]>
To: <[email protected]>, "Craig Robson" <[EMAIL PROTECTED]>
Subject: Re: New clutch problem
Message-ID: <[EMAIL PROTECTED]>

not sure if this applies to the E46 M3 or if it is even related to your
problem - but the symptoms are the clutch slips.

http://www.uucmotorwerks.com/html_techtip/techtips/check_valve.htm

Marco

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of Gary Derian
Sent: Sunday, July 10, 2005 9:09 AM
To: Craig Robson; [email protected]
Subject: Re: [UUC] New clutch problem


By installing a lightweight flywheel, you have removed a large vibration
damper designed to stop transmission rattle when idling in neutral.
Consider it a badge of honor, not a problem.

The clutch should not chatter, though.  Generally clutch chatter is caused
by contamination.  Try slipping the clutch to heat it up and burn off the
contamination.  Don't do it too much, though.

A loose or misaligned center bearing or flex disk can cause a vibration that
seems like clutch chatter.

Gary Derian



> All:
>    I had the UUC lightweight flywheel and M5 clutch installed by a
> professional on my E46 M3, but I am having some problems.
>
> First, I am getting a lot of clutch chatter, so much that it appears to
> have
> ruined my center support bearing (or could that have been caused by
> something else like a loose bolt somewhere?). What could be causing the
> chatter? The Bentley did not have the torque value for the flywheel so he
> looked it up in his computer and he says it gave him two values of which
> he
> chose the higher (90 something ft-lbs). For the bolts holding the clutch
> to
> the flywheel, he says he did one or two ft-lbs more than factory spec, so
> like 27 I think.
>
> Second problem I am having is the transmission rattle. We replaced the
> fluid
> with Motul 75-90 (what was handy) and it had little to no effect. Should I
> try Redline MTL 90? My mechanic thinks it is the input shaft bearing on
> the
> transmission, but I disagree. I think it is just the rattle since if I
> turn
> the A/C off it goes to a bearable level. Should I try ordering a chip and
> bumping the idle up a bit?
>
>
> Craig Robson
> '01 M3<-- please help me!
>
> ----- Original Message -----
> From: <[EMAIL PROTECTED]>
> To: <[email protected]>
> Sent: Sunday, July 10, 2005 1:28 AM
> Subject: [UUC] <E30> Engine removal
>
>
>> well I started the procedure to get the engine ready for extraction on
>> the
>> e30 but I'm puzzled by some things in the Bentley.
>>
>> 1. Why does the Bentley call for removal of some of the sensor connectors
>> (eg. the oil pressure sensor under the oil filter) when they'll just come
>> with the main bus which I pulled from the ECU? Also why take off the
>> coolant pipe that goes along the front of the engine? I can't see a need
>> for it. And why remove the fuel injector, speed sensor , and purge valve
>> connectors?
>>
>> 2. If I pull the tranny and engine as a unit, why do I have to remove the
>> starter? I've taken the wiring off the selonoid before I realized it
>> probably wasn't necessary. I'll have to try to figure out where they go
>> back later.
>>
>> 3. Where's that rear pick up point for the hoist?
>>
>> 4. Is it better to remove the down pipes from the exhaust manifold or to
>> remove the manifold itself before taking out the motor?
>>
>> 5. Why does the oil dipstick have to be removed?
>>
>> Jenny, Brett, Jack , Carlos?
>>
>> Thanks, Kevin
>>
>>  ----------------------------------------------------------------
>>  This  e-mail  communication is confidential and is intended only
>>  for  the individual(s) or entity named above and others who have
>>  been  specifically  authorized to receive it. If you are not the
>>  intended  recipient,  please  do not read, copy, use or disclose
>>  the  contents of this communication to others. Please notify the
>>  sender  that  you have received this e-mail in error by replying
>>  to  the e-mail.  Please then delete the e-mail and any copies of
>>  it. Thank you.
>>  ----------------------------------------------------------------
>>
>>
>> Search the
>> ARCHIVES:http://www.mail-archive.com/[email protected]
>>
>>
>>
__________________________________________________________________________
>> In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.
>>
>> UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
>> Short Shifter - accept no substitutes!
>> 908-874-9092 . http://www.uucmotorwerks.com
>
> Search the ARCHIVES:http://www.mail-archive.com/[email protected]
>
>
> __________________________________________________________________________
> In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.
>
> UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
> Short Shifter - accept no substitutes!
> 908-874-9092 . http://www.uucmotorwerks.com
>


Search the ARCHIVES:http://www.mail-archive.com/[email protected]


__________________________________________________________________________
In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.

UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
Short Shifter - accept no substitutes!
908-874-9092 . http://www.uucmotorwerks.com


------------------------------

Date: Sun, 10 Jul 2005 08:01:51 -0700 (PDT)
From: Carlos Lopez <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED], [email protected]
Subject: Re: <E30> Engine removal
Message-ID: <[EMAIL PROTECTED]>

--- [EMAIL PROTECTED] wrote:
> Jenny, Brett, Jack , Carlos?

I get to do this next month (removal).  Karl (on the list) and I just
installed his engine a couple of weeks ago and we did it with the
engine and tranny attached along with all the other stuff also
(including the headers).  This is a race car so there's no A/C stuff in
the way.  The angle of attack was the big issue and we had to re-adjust
the chains once to get us a steeper angle so the trans cleared the
firewall.  Other than that it was pretty simple.  Because we had to set
the engine down at one point to re-adjust the hoist it probably caused
the oil pan gasket to move and now there's a bit of an oil leak.  We're
fixing that today.

We didn't break anything plastic or otherwise AFAIK.

I agree with Jenny, labelling everything is *super* important.  I
bought a label maker so mine is going to be all neat looking and crap
when I disconnect stuff.  Pics may also help.  I know a couple of times
we used my car to check wire routings and connector locations and that
type of stuff.  The car (Karl's race car) is going to be at Nelson
Ledges next weekend if anyone in the NE Ohio area happens to drop by
(say hello).  Other listers will be there as well, Rich D., Kathy L.,
and others.

Carlos.


                
____________________________________________________
Sell on Yahoo! Auctions – no fees. Bid on great items.  
http://auctions.yahoo.com/

------------------------------

Date: Sun, 10 Jul 2005 12:09:18 -0400
From: "Gary Derian" <[EMAIL PROTECTED]>
To: "Kevin Kiely" <[EMAIL PROTECTED]>, <[email protected]>
Subject: Re: <E30> Engine removal
Message-ID: <[EMAIL PROTECTED]>

I attached the chains to the engine mount arms.  The transmission naturally
falls when the engine is lifted.  Put a floor jack there to support it.
Thread the chain between the exhaust manifolds to keep the engine from
flipping upside down.

Pull and install the engine with the engine harness attached.  There are far
fewer connections that way.

Gary Derian


> well I started the procedure to get the engine ready for extraction on the
> e30 but I'm puzzled by some things in the Bentley.
>
> 1. Why does the Bentley call for removal of some of the sensor connectors
> (eg. the oil pressure sensor under the oil filter) when they'll just come
> with the main bus which I pulled from the ECU? Also why take off the
> coolant pipe that goes along the front of the engine? I can't see a need
> for it. And why remove the fuel injector, speed sensor , and purge valve
> connectors?
>
> 2. If I pull the tranny and engine as a unit, why do I have to remove the
> starter? I've taken the wiring off the selonoid before I realized it
> probably wasn't necessary. I'll have to try to figure out where they go
> back later.
>
> 3. Where's that rear pick up point for the hoist?
>
> 4. Is it better to remove the down pipes from the exhaust manifold or to
> remove the manifold itself before taking out the motor?
>
> 5. Why does the oil dipstick have to be removed?
>
> Jenny, Brett, Jack , Carlos?
>
> Thanks, Kevin
>
> ---------------------------------------------------------------- 
> This  e-mail  communication is confidential and is intended only
> for  the individual(s) or entity named above and others who have
> been  specifically  authorized to receive it. If you are not the
> intended  recipient,  please  do not read, copy, use or disclose
> the  contents of this communication to others. Please notify the
> sender  that  you have received this e-mail in error by replying
> to  the e-mail.  Please then delete the e-mail and any copies of
> it. Thank you.
> ---------------------------------------------------------------- 
>
>
> Search the ARCHIVES:http://www.mail-archive.com/[email protected]
>
>
> __________________________________________________________________________
> In memory of Michel Potheau - friend, enthusiast, founder of the BMW CCA.
>
> UUC Motorwerks - BMW Performance Fine-tuning and home of the Ultimate
> Short Shifter - accept no substitutes!
> 908-874-9092 . http://www.uucmotorwerks.com
>



------------------------------

Date: Sun, 10 Jul 2005 15:15:18 -0400 (EDT)
From: [EMAIL PROTECTED]
To: [EMAIL PROTECTED] (KMS- Brett Anderson)
Cc: [email protected] (UUC Digest)
Subject: Re: E36 325i question - OBD1 O2 sensor & MPG needle
Message-ID: <[EMAIL PROTECTED]>

>From KMS- Brett Anderson
>
>The mpg meter is not directly related to the O2 sensor.
>
>The mpg meter is moved by the DME, which is reporting fuel consumption.  So,
>indirectly, the O2 sensor is related to the meter.
>
>However, the O2 sensor also has nothing to do with how the engine runs when
>cold.  It takes up to 3 or 4 minutes before the O2 sensor comes on line, so
>cold rough running is indicitive of another problem, usually an air leak or
>a bad coolant temp sender. It could also be a defective fuel injector or
>pressure regulator.
>
>During this rough running stage, the DME will be varying fuel input in an
>attempt to stabilize the idle.  As the mpg meter is run from a algorithm of
>fuel injector duty cycle, known (assumed) fuel pressure and vehicle speed,
>it will bounce around as the duty cycle is changed by the DME.
>

Wow! This is great information for the problem I am chasing on my E30...

My car has all the classic signs of running rich, except that I never get a
CE light and it all seems happy once it warms up. The lack of CE light and
the exhaust cleaning up once it warms up leads me to suspect something other
than the O2 sensor.

How does the DME determine when to switch from open loop to closed loop
operation? Is this a timer internal to the DME, the thermo-time switch, or
something based on the coolant temperature sensor? Is the temperature sensor
that talks to the DME also the one that talks to the temperature gauge
inside the car? 

Also, anyone have a good lead on an exhaust for an E30 325i? One of my
exhaust tips had an argument with an extra steep driveway I was backing into
and punched the back of my muffler open. I now have a distinctly
"coffee-can" sounding exhaust... but I can tell that it is definitely rich
on start up. Lot's of unburnt fuel smell.

-- Joe

--
Joseph M. Krzeszewski                       Network Operations
[EMAIL PROTECTED]                        Jack of All Trades, Master of None... 
Yet

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Date: Sun, 10 Jul 2005 13:06:59 -0700
From: John Bolhuis <[EMAIL PROTECTED]>
To: [email protected]
Subject: Re: E36 325i question - OBD1 O2 sensor & MPG needle
Message-ID: <[EMAIL PROTECTED]>

On Sun, Jul 10, 2005 at 03:15:18PM -0400, [EMAIL PROTECTED] wrote:

> How does the DME determine when to switch from open loop to closed
> loop operation? Is this a timer internal to the DME, the thermo-time
> switch, or something based on the coolant temperature sensor?

There may be some internal timer, but it's pretty easy for the DME to 
just watch the output of the O2 sensor.  When it's cold, there is no 
output.  When it heats up enough to work, the sensor output will climb 
into the "rich" zone.  At that point, the DME can start varying the 
mixture to keep it homed in on "normal".

-- 
 "It is an honor to be Cookie Monster."
   -Sesame Street spokeswoman Audrey Shapiro 

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