maf reading to high setting code p0171? - Page 2 - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


2000-2005 Discuss your 2000-2005 Bonneville SE, SLE, and SSEi Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Reply
 
 
 
Thread Tools Search this Thread
Old 08-27-2007, 07:40 PM   #11
Senior Member
Posts like a Turbo
 
Join Date: May 2007
Location: Sycamore, IL (ILRt. 64 and ILRt. 23)
Posts: 303
Thanks: 0
Thanked 0 Times in 0 Posts
01BonneSC is on a distinguished road
Default

Could this bee a bad check ball/valve on the return side?
01BonneSC is offline   Reply With Quote
Old 08-28-2007, 09:24 AM   #12
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

Quote:
Originally Posted by 01BonneSC
Could this bee a bad check ball/valve on the return side?
The only thing on the return side should be the regulator. But since the system isn't holding pressure it'* most likely internal to the pump.
BillBoost37 is offline   Reply With Quote
Old 08-28-2007, 12:38 PM   #13
Senior Member
True Car Nut
 
Join Date: Jul 2004
Location: Grand Rapids, Mi
Posts: 5,656
Thanks: 0
Thanked 0 Times in 0 Posts
Archon is on a distinguished road
Default

I agree with Bill. The extra tests that it shows (with special tools that the dealer has) is to disconnect the fuel lines, pressurize the rail, and see if it holds pressure. If it leaks down, the checks from there are FPR and injectors. If you are not getting gas into the FPR vacuum line, that would eliminate that, and as quickly as it leaks down, I would doubt an injector.

The other half is then tested, and the solutions for that if it leaks down are lines or the pump itself. So, if the FPR and lines have been ruled out...it leaves the pump.
Archon is offline   Reply With Quote
Old 09-07-2007, 07:38 PM   #14
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Mar 2004
Location: grand rapids MI.
Posts: 45
Thanks: 0
Thanked 0 Times in 0 Posts
bigdawg56 is on a distinguished road
Default

Replaced fuel pump now everything is alright. no more codes no more hard starts. I think the pump was bad from the begining due to the fact that it started very hard but i was told by tim at zzp that this was normal just turn the key slower. now all i have to do is bump the key and it fires right up!
bigdawg56 is offline   Reply With Quote
Old 09-08-2007, 03:39 PM   #15
DINOSAURUS BOOSTUS

Expert Gearhead
 
BillBoost37's Avatar
 
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default

Leak down isn't normal. Sorry but I think Tim is full of it on that one. Whether the pump is new or a performance pump... it should hold pressure to start the car.

I have seen plenty of other vehicles with issues like this and it all comes down to the check valve in the pump as being stuck open or busted.
BillBoost37 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
P0171 and MAF javaroast 1992-1999 17 06-10-2009 01:24 PM
P0102, P0171. MAF, Lean Falcon123 1992-1999 10 11-02-2005 03:12 PM
What should the MAF (Mass Air Flow) gm/sec reading be ? Dutch2005 1992-1999 1 10-15-2005 12:27 AM
SES light code P0171 Baileyjack 2000-2005 3 08-04-2003 08:46 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 03:31 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.