Buick When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

2003 Rendezvous cx problem

Thread Tools
 
Search this Thread
 
Old Sep 23, 2014 | 04:51 PM
  #1  
nbul94's Avatar
Thread Starter
Junior Member
 
Joined: Jul 2014
Posts: 7
Likes: 0
nbul94 is on a distinguished road
Default 2003 Rendezvous cx problem

I am having a starting problem. Most of the time it will fire on the first crank, sputter and die, the second crank it will start right up. Other times is will crank and crank with no fire, but if i spray a little carb cleaner in the intake it will fire up and run perfect. I have 50 psi fuel pressure, and the regulator has been replaced, and the fuel filter. I believe it to be a security problem as the light has come on a few times. I read the codes and here is what it gave.

BCM codes: U1016, U1040, B2961.

Powertrain codes: P1626, U1040, U1064, U1300.

I have done some searching and found the key switch is common and the bcm but i dont want the throw parts at it. I'm seeing if any one has experienced this at all? Thanks
Reply
Old Sep 23, 2014 | 05:45 PM
  #2  
Mike's Avatar
Retired
Certified Car Nut
 
Joined: Jul 2003
Posts: 17,960
Likes: 1,839
From: Dark Side, AZ
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

50 psi may not be enough to make it run. Some V6'* need about 43, some others 55+

But, you have 2 U codes thats saying the PCM can't talk to the BCM and the BCM can't talk to the PCM. Both of them are reporting this. So it seems like we have a bad link between the 2 modules. And probably the best way to test this is to get to a dealer that has a Tech2 diagnostic tool that can "talk" to every single module in the car.
Reply
Old Sep 24, 2014 | 10:37 AM
  #3  
nbul94's Avatar
Thread Starter
Junior Member
 
Joined: Jul 2014
Posts: 7
Likes: 0
nbul94 is on a distinguished road
Default

I have a snap on scanner where I can see all live data of both modules, and turn off really anything I want to. Can tech 2 do more then this?
Reply
Old Sep 24, 2014 | 07:23 PM
  #4  
Mike's Avatar
Retired
Certified Car Nut
 
Joined: Jul 2003
Posts: 17,960
Likes: 1,839
From: Dark Side, AZ
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

Of course the Tech2 can do more. Its designed to be the highest diagnostic tool for GM vehicles. Its the only one that can reprogram GM modules, stereos, PCM'* BCM'*, etc etc.
Reply
Old Sep 24, 2014 | 10:25 PM
  #5  
Tech II's Avatar
Senior Member

True Car Nut
 
Joined: Feb 2014
Posts: 2,878
Likes: 1,097
From: Worcester, Ma.
Tech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond repute
Default

If the vehicle cranks over, the PCM is getting a signal from the PassKey III module......thus it grounds the starter relay, and the fuel pump relay......I am not sure if the PCM receives the fuel enable signal from the PK3 moduel or the BCM....

The fact it starts, with a shot of carb cleaner, may mean the fuel pressure is borderline as Mike has suggested....maybe some one can look up the fuel pressure specs....

B2961 and P1626 have to do with the theft deterrent system......what you are going to have to do, is clear the codes and when the vehicle won't start, recheck to see which codes may have returned......comm codes are hard to diagnose, especially if intermittent....
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
johnnyu
Buick
2
May 18, 2015 09:32 PM
csmith161
Buick
4
May 16, 2015 08:34 PM
steph197755
Buick
3
Dec 29, 2011 06:32 PM
gosox
Buick
3
Jan 13, 2011 04:15 PM
redwingsfan34
Lounge
13
Aug 8, 2007 06:27 PM




All times are GMT -4. The time now is 06:24 PM.