sluggishness and cruise control problems
 

I took my 2003 Passat in for "engine light" service a few weeks ago.
They apparantly replaced one of the ignition coils. Ran great until
this past week.

Then not only did it suddenly develop bouts of "sluggishness" (poor
accelleration, rougher idle), the cruise control doesn't work.

While I wait for the service appointment, does this sound like anything
in particular? I was a bit surprised that they both went out at about
the same time.

--
Darren Dunham
Senior Technical Consultant TAOS http://www.taos.com/
Got some Dr Pepper? San Francisco, CA bay area
< This line left intentionally blank to confuse you. >

Darren Dunham wrote:
> I took my 2003 Passat in for "engine light" service a few weeks ago.
> They apparantly replaced one of the ignition coils. Ran great until
> this past week.
>
> Then not only did it suddenly develop bouts of "sluggishness" (poor
> accelleration, rougher idle), the cruise control doesn't work.
>
> While I wait for the service appointment, does this sound like
> anything in particular? I was a bit surprised that they both went
> out at about the same time.

Some cruse controls are vacuum controlled. A loss of vacuum could cause
both problems.

--
Joseph Meehan

26 + 6 = 1 It's Irish Math

Joseph Meehan wrote:
>
> Darren Dunham wrote:
> > I took my 2003 Passat in for "engine light" service a few weeks ago.
> > They apparantly replaced one of the ignition coils. Ran great until
> > this past week.
> >
> > Then not only did it suddenly develop bouts of "sluggishness" (poor
> > accelleration, rougher idle), the cruise control doesn't work.
> >
> > While I wait for the service appointment, does this sound like
> > anything in particular? I was a bit surprised that they both went
> > out at about the same time.
>
> Some cruse controls are vacuum controlled. A loss of vacuum could cause
> both problems.

The Passat could be different, but on my '87 GTi the cruise is vacuum
operated, but it has its own vacuum pump and does not use engine vacuum.

As I understand it, the cruise control function on newer VWs (with
throttle by wire) is built into the ECU firmware. I would imagine that
if the ECU detects something wrong, it could automatically cancel the
cruise.

Randolph wrote:
> Joseph Meehan wrote:
>>
>> Darren Dunham wrote:
>>> I took my 2003 Passat in for "engine light" service a few weeks ago.
>>> They apparantly replaced one of the ignition coils. Ran great until
>>> this past week.
>>>
>>> Then not only did it suddenly develop bouts of "sluggishness" (poor
>>> accelleration, rougher idle), the cruise control doesn't work.
>>>
>>> While I wait for the service appointment, does this sound like
>>> anything in particular? I was a bit surprised that they both went
>>> out at about the same time.
>>
>> Some cruse controls are vacuum controlled. A loss of vacuum
>> could cause both problems.
>
> The Passat could be different, but on my '87 GTi the cruise is vacuum
> operated, but it has its own vacuum pump and does not use engine
> vacuum.

I wonder if some other engine controls are feed off that same vacuum?

>
> As I understand it, the cruise control function on newer VWs (with
> throttle by wire) is built into the ECU firmware. I would imagine that
> if the ECU detects something wrong, it could automatically cancel the
> cruise.

I believe mine is as well, but I have not bothered to check. I will
have to open up my Bentley CD and find out some day.

--
Joseph Meehan

26 + 6 = 1 It's Irish Math

On Sat, 22 Jan 2005, Darren Dunham wrote:

> Then not only did it suddenly develop bouts of "sluggishness" (poor
> accelleration, rougher idle), the cruise control doesn't work.
>
> While I wait for the service appointment, does this sound like anything
> in particular? I was a bit surprised that they both went out at about
> the same time.

Check to see if your rear brake lights are working. The brake light switch
went in our '02 Jetta wagon recently (and as it turns out there was a
recall but we hadn't gotten a notice) and the cruise not functioning is
what clued me into a problem in the first place.

As you can imagine, you really don't want to be driving around with no
brake lights.

Craig

Some faults will turn off the cruise along with AC compressor. BTW, the
cruise is all electric.

"Darren Dunham" > wrote in message
m...
>I took my 2003 Passat in for "engine light" service a few weeks ago.
> They apparantly replaced one of the ignition coils. Ran great until
> this past week.
>
> Then not only did it suddenly develop bouts of "sluggishness" (poor
> accelleration, rougher idle), the cruise control doesn't work.
>
> While I wait for the service appointment, does this sound like anything
> in particular? I was a bit surprised that they both went out at about
> the same time.
>
> --
> Darren Dunham
> Senior Technical Consultant TAOS http://www.taos.com/
> Got some Dr Pepper? San Francisco, CA bay area
> < This line left intentionally blank to confuse you. >

I goofed around with brake switches when both of my brake light bulbs
burned out. No brake lights and no cruise.

Craig Faison > wrote:

>On Sat, 22 Jan 2005, Darren Dunham wrote:
>
>> Then not only did it suddenly develop bouts of "sluggishness" (poor
>> accelleration, rougher idle), the cruise control doesn't work.
>>
>> While I wait for the service appointment, does this sound like anything
>> in particular? I was a bit surprised that they both went out at about
>> the same time.
>
>Check to see if your rear brake lights are working. The brake light switch
>went in our '02 Jetta wagon recently (and as it turns out there was a
>recall but we hadn't gotten a notice) and the cruise not functioning is
>what clued me into a problem in the first place.
>
>As you can imagine, you really don't want to be driving around with no
>brake lights.
>
>Craig


Jim B.

wrote:
>
> I goofed around with brake switches when both of my brake light bulbs
> burned out. No brake lights and no cruise.

On some VW's (as you have found out) the cruise control will not work if
all the brake bulbs are burned out. Having all bulbs burned out will
cause the cruise to "believe" that the brake pedal is pressed. For A2
cars, I know this to be the case for some years, not for others. For the
Passat I do not know the details.

Craig Faison > wrote:
> On Sat, 22 Jan 2005, Darren Dunham wrote:

>> Then not only did it suddenly develop bouts of "sluggishness" (poor
>> accelleration, rougher idle), the cruise control doesn't work.
>>
>> While I wait for the service appointment, does this sound like anything
>> in particular? I was a bit surprised that they both went out at about
>> the same time.

> Check to see if your rear brake lights are working. The brake light switch
> went in our '02 Jetta wagon recently (and as it turns out there was a
> recall but we hadn't gotten a notice) and the cruise not functioning is
> what clued me into a problem in the first place.

> As you can imagine, you really don't want to be driving around with no
> brake lights.

No kidding. In fact, the lights were out.

So the cruise/brake light association I get. What that does or doesn't
have to do with the engine performance, I don't know.

It's under warranty and got dropped off at the dealer this morning.
Hopefully I'll know soon.

--
Darren Dunham
Senior Technical Consultant TAOS http://www.taos.com/
Got some Dr Pepper? San Francisco, CA bay area
< This line left intentionally blank to confuse you. >

On Thu, 27 Jan 2005, Darren Dunham wrote:

> So the cruise/brake light association I get. What that does or doesn't
> have to do with the engine performance, I don't know.
>
> It's under warranty and got dropped off at the dealer this morning.
> Hopefully I'll know soon.

Let us know what they tell you... we didn't have any running issues when
the switch failed on our Jetta.

Needless to say, I wasn't very pleased to find out that my wife & kid had
been driving around w/no brake lights for who knows how long. My wife
never uses the cruise, and I rarely do, so we really have no idea how long
it had been that way.

Craig