Home | Contact Us | FAQ | Search & Site Map | Link to Us
Sign In | Join | Other 45 Sites in Network
HomeAnnouncements
Discussion Groups
By Brand
BMWChevroletDodgeFordGMHondaLexusMercedes-BenzNissanPeugeotToyotaVolkswagenOther Brands
By Topic
4x4 CarsRVsDrivingMaintenance & RepairCar AudioCollectible Cars
Country Specific
Australian ForumsUK Forums
ArticlesAuto InsuranceBuyingCars & TechnologyMaintenanceMiscellaneousSafety
DMV Resources
Related Topics
MotorcyclesBoatsMore Topics ...

Car Forum / Chevrolet / Chevrolet Trucks / July 2006

Tip: Looking for answers? Try searching our database.

MIL ON : Code P0101

Thread view: 
Enable EMail Alerts  Start New Thread
Thread rating: 
Steve W. - 11 Jul 2006 01:09 GMT
2002 Chevy Blazer 4.3 Vin W engine, Automatic, 4X4, 91,000 miles

Has this as an intermittent problem. 99% of the time it happens while
going uphill under load.
Code lists out as MAF : Circuit range performance problem.
The MAP value is always the same in the freeze data. It does change when
viewing live data though. It never shows a negative pressure in the
intake though even when going downhill with a closed throttle where I
would think the engine would draw a vac in the intake, so I am thinking
that it is possibly the real problem.

Typical freeze data read with an Actron CP9145 scanner.

TPS     : 70 - 73.7 % -
RPM    : 3000 - 3480
load     : 50 - 59%
MAF     : 11 - 12.9
MAP     : 26.9  "Hg
Speed : 40 - 46 Mph

MIL light shuts off after 3 restarts and it may go 2 weeks without it
coming on again.

It has had a new set of plugs, wires and the intake gaskets were changed
out with no effect on the code (done more as a preventative anyway since
I had some time to work on it and this problem doesn't seem to effect
the drivability). Cleaned the MAF and swapped it with a different one,
same readings with the new unit so I swapped them back.

Figure I'd ask for other opinions.

Signature

Steve W.

Shep - 11 Jul 2006 01:56 GMT
check the map readings key on engine off, then check it running at idle see
what you have, the running readings are the difference between the
atmospheric press. and the engine vacuum. It is possible the pcm is being
fooled by what it percieves to be expected air flow from the maf based on
engine load calculated from the tps and map. Going up hill under load should
not be 26.9, that is atmospheric pressure, something is awry. Not completely
familiar with this engine ,does it have a map?
> 2002 Chevy Blazer 4.3 Vin W engine, Automatic, 4X4, 91,000 miles
>
[quoted text clipped - 26 lines]
>
> Figure I'd ask for other opinions.
Steve W. - 11 Jul 2006 18:27 GMT
Shep,
MAP is in the intake on the pass side. KOEO it shows 26.9.  Idle shows
it at 13.4 - 12.2. It seems to track OK with throttle position though.
TPS is clean with no opens through it's range. Just want to be a PIA. I
was hoping that it was a bad harness connector or bad vac. line. Checked
them over and nothing wrong there.

Signature

Steve W.
Near Cooperstown N.Y.

> check the map readings key on engine off, then check it running at idle see
> what you have, the running readings are the difference between the
[quoted text clipped - 35 lines]
>
> ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet
News==----
> http://www.newsfeeds.com The #1 Newsgroup Service in the World!
120,000+ Newsgroups
> ----= East and West-Coast Server Farms - Total Privacy via Encryption
=----
Shep - 11 Jul 2006 20:54 GMT
map/baro seems lo, what is your altitude? I am in the LK George are.
> Shep,
> MAP is in the intake on the pass side. KOEO it shows 26.9.  Idle shows
[quoted text clipped - 77 lines]
> ----= East and West-Coast Server Farms - Total Privacy via Encryption
> =----
Steve W. - 13 Jul 2006 06:29 GMT
That is why I'm thinking the MAP is the problem. I think I have one that
will fit off another vehicle so I'll just swap it and look at those
readings. I was up in your area for Americade.

Signature

Steve W.

> map/baro seems lo, what is your altitude? I am in the LK George are.
> > Shep,
[quoted text clipped - 73 lines]
> >
> > ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure
Usenet
> > News==----
> > http://www.newsfeeds.com The #1 Newsgroup Service in the World!
120,000+
> > Newsgroups
> > ----= East and West-Coast Server Farms - Total Privacy via
Encryption
> > =----
>
> ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet
News==----
> http://www.newsfeeds.com The #1 Newsgroup Service in the World!
120,000+ Newsgroups
> ----= East and West-Coast Server Farms - Total Privacy via Encryption
=----
Shep - 13 Jul 2006 15:44 GMT
My daughter works for Americade, handled all the registrations.
> That is why I'm thinking the MAP is the problem. I think I have one that
> will fit off another vehicle so I'll just swap it and look at those
[quoted text clipped - 112 lines]
> ----= East and West-Coast Server Farms - Total Privacy via Encryption
> =----
Steve W. - 19 Jul 2006 07:00 GMT
Well finally had a chance to work on the beast. Tossed a new MAP in and
checked the readings.
Had 29.2 KOEO with a new one. Idle showed 11.4.
Ran it through the gauntlet and no light.
Will see if is stays off.
Signature

Steve W.

> My daughter works for Americade, handled all the registrations.
> > That is why I'm thinking the MAP is the problem. I think I have one that
[quoted text clipped - 101 lines]
> >>
> >> ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure
Usenet
> > News==----
> >> http://www.newsfeeds.com The #1 Newsgroup Service in the World!
> > 120,000+ Newsgroups
> >> ----= East and West-Coast Server Farms - Total Privacy via
Encryption
> > =----
> >
> > ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure
Usenet
> > News==----
> > http://www.newsfeeds.com The #1 Newsgroup Service in the World!
120,000+
> > Newsgroups
> > ----= East and West-Coast Server Farms - Total Privacy via
Encryption
> > =----
>
> ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet
News==----
> http://www.newsfeeds.com The #1 Newsgroup Service in the World!
120,000+ Newsgroups
> ----= East and West-Coast Server Farms - Total Privacy via Encryption
=----
 
Sign In
Join
My Latest Posts
My Monitored Threads
My Blog
My Photo Gallery
My Profile
My Homepage

Start New Thread
Enable EMail Alerts
Rate this Thread



©2008 Advenet LLC   Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.