Hard start, cold start problem, rough idle...now IdleSwitch/MAF code

[Bernie Benz]

You¹re right, Derek.

The crankcase vent system vents after the MAF and into the compressor. MAF
oil contamination is only from K&N downgrades. My error.

Bernie 

> From: "Derek Pulvino" <dbpulvino at hotmail.com>
> Date: Mon, 03 Jul 2006 10:21:32 -0700
> To: b.benz at charter.net
> Cc: 200q20v at audifans.com
> Subject: Re: Hard start, cold start problem, rough idle...now IdleSwitch/MAF
> code
> 
> Well, I've erased the fault codes and will see what comes up again.  I also
> checked sjm's site, and it appears to be a fairly common occurrence for the
> solder joints at the idle switch and potentiometer to get sporadic as the
> car gets older.
> 
> As to the oil on the MAF, what's the mechanism?  Crankcase vent hose
> attaches on the "downwind" side of the MAF, with the only thing I can think
> of before the MAF being the air filter.
> 
> Derek P
> 
>> Derek,
>> 
>> Your MAF codes could also be real if, as I remember, you have very high oil
>> consumption. MAF may be contaminated beyond its ability to burn off by
>> excessive vapor blow by injected ahead of the MAF.
>> 
>> Bernie
>> 
>>> From: "Derek Pulvino" <dbpulvino at hotmail.com>
>>> Date: Sun, 02 Jul 2006 13:16:33 -0700
>>> To: brfoster at gmail.com, b.benz at charter.net
>>> Cc: 200q20v at audifans.com
>>> Subject: Re: Hard start, cold start problem, rough idle...now Idle
>> Switch/MAF
>>> code
>>> 
>>> Ok, so I ran the fault codes yesterday and got two that seem to make
>> sense.
>>> First was for the idle switch...second for the MAF sensor.
>>> 
>>> The idle switch makes sense, but I do still wonder why it seems to only
>>> effect the idling upon restarting a warm car and not when the car is
>> started
>>> cold...even after the cold started car has warmed up, and also why this
>>> problem only creeps up when the weather is warm.  I checked the
>> open/closed
>>> continuity of the switch after getting the code and it's fine...maybe
>> need
>>> to do the check on a warm car as that's when the problem arises.
>>> 
>>> On the MAF, problems there do make seem cogent with the odd stumbling
>> I've
>>> been getting, but I also wonder if an idle switch problem "confused" the
>>> system into throwing this (MAF) code.
>>> 
>>> Ran the output tests this morning...everthing cycles just as it's
>> supposed
>>> to, including the ISV.
>>> 
>>> Any input of similar experiences from anybody?  Oh, and my car has
>> started
>>> to require more cranking on cold starts now.
>>> 
>>> Derek P
>>> 
>