'02 Envoy OBD II Codes P0105 & related issues?

[davida07]

I've recently replaced the alterator in my Envoy. I have also had an on going issue with the service engine light going on intermitently. When the light is on, engaging the blower motor bogs down the vehicle. If parked under these conditions, the rpms fluctuate greatly and can stall the vehicle. I've also noticed that the cruise does not function when the service engine light is on.
The OBD code suggests a malfunction existing in the electric circuit for the manifold absolute pressure sensor or the barometric pressure sensor.
Probable cause:

1. Vacuum hose off, cracked or passage blocked-Engine mechanical timing condition
2. Throttle body intake tube loose, off, or cracked
3. BARO (Barometer)?MAP (Manifold Absolute Pressure) defective
4. VAF(Vane Air Flow)MAF (Mass Air Flow) sensor dirty or defective.

Are my problems related, alternator, service engine light, blower moter? Any suggests on where to begin. The car is running at present, but I'd like to follow up on these other isssues. I have not found any broken or disonnected vacuum lines.

[maxwedge]

Welcome to AF. You need a full scan to look at he map/baro function to really see what is happening. Your 105 is a generic code description, some of which does not apply to this engine. See this link. http://service.gm.com/gmspo/mode6/pd.../2002file2.pdf

[brian 1]

there is a bulletin on this code with these symptoms.all of what you describe,fit this bulletin.you have to clean the throttle bore due to excessive carbon build up.

[maxwedge]

Not disagreeing with you here, but I've never seen a carboned up TB cause a map sensor code, a large vacuum leak maybe, but even if the throttle stuck partially open the pcm can easily compensate for this issue, got a direct reference to this bulletin?

[brian 1]

i know but i never said this will defenitly fix there proble.i can get these bulletins directly of si (service information).this bulletin came out a year ago.i suggested this because it applys and it's the easyest thing to check and it doesent really cost much.

[envoyxuv]

Originally Posted by brian 1

i know but i never said this will defenitly fix there proble.i can get these bulletins directly of si (service information).this bulletin came out a year ago.i suggested this because it applys and it's the easyest thing to check and it doesent really cost much.

Just checked it out.... here's the doc#1884435

[davida07]

Originally Posted by envoyxuv

Just checked it out.... here's the doc#1884435

I don't see the document. Is it attached or do I need to go elsewhere to veiw it? Does this encompass the issue with the blower motor?

[BRD]

Thanks for the link, Max. There's a lot of valuable info via that site.

Re David's search for that "document" by number, sometimes if you google it by "GM document xxxxxxxxx" it'll pop up in somebody's post to one of the automotive boards on the web (there are MANY). In most cases a "document" of that type is also a Technical Service Bulletin ("TSB"). Autodata sells TSBs via its pay site, but if it were me I'd call a local GM dealer's service dept (like the dealer's where I bought my last GM veh) and ask them to pull up the GM "document" by number and fax me a copy, or e-mail it to me if it's in their digital files. It won't break their hearts if you're able to fix the prob without taking the veh in.

Last, Max is right that crud in the throttle body by itself is an unlikely cause of David's problem. He may end up at the dealer's svc dept anyway (that's why it doesn't bother them if he takes a stab at it first). Check the owner's manual in the chapter that covers the "emissions" system. The term refers to quite a few components beyond the basic pollution control items. GM's factory warranty covers emissions defects for 7 or 8 years, subject to a mileage limit that I don't have in front of me.

[maxwedge]

70/80k on the exhaust system from the cat forward, and the pcm, thats it. Calif/Federal do have other limitations, check you warranty booklet.

[envoyxuv]

Originally Posted by davida07

I don't see the document. Is it attached or do I need to go elsewhere to veiw it? Does this encompass the issue with the blower motor?

...sorry about that... here's the rest of it:

Models:2004-2007 Buick Rainier

2002-2007 Chevrolet TrailBlazer

2004-2007 Chevrolet Colorado

2002-2007 GMC Envoy

2004-2007 GMC Canyon

2002-2004 Oldsmobile Bravada

2006-2007 HUMMER H3

2005-2007 Saab 9-7X

with any of the following engines:

2.8L (VIN 8 - RPO LK5)

2.9L (VIN 9 - RPO LLV)

3.5L (VIN 6 - RPO L52)

3.7L (VIN E - RPO LLR)

4.2L (VIN S - RPO LL8)

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:

On rare occasions, a SES light may be experienced due to DTCs P0105, P0106, and/or P0506. There may or may not be an idle complaint accompanying the SES light. This may be due to excessive carbon build up in the throttle body.
Recommendation/Instructions:

If the SI diagnostics do not isolate a cause for this concern, clean the throttle body bore and plate for evaluation.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.