1997 Pontiac Bonneville multiple codes

Tiny
KLIVERGOOD
  • MEMBER
  • 1997 PONTIAC BONNEVILLE
  • 3.8L
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 209 MILES
Originally the maf sensor went out, I purchased a new one and installed it also changed the thermostat at same time. The check engine light went off for a day then came on and car would have running issues on initial start up. Had codes read again and now throwing maf code, throttle positioning sensor code, temp sensor code and saying left bank running lean. Any help would be greatly appreciated!
Tuesday, March 3rd, 2015 AT 8:00 AM

9 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,645 POSTS
Have you checked for vacuum leaks? Have you checked fuel pump pressure?
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2015 AT 8:41 AM
Tiny
KLIVERGOOD
  • MEMBER
  • 5 POSTS
How can I check the fuel pump pressure? Also when car first starts the voltage and oil pressure guage are way low then they fly up and car idles correct again. Looked back through all the sensor wires I disconnected to get to thermostat and everything is connected correctly. Weird that 4 sensors go at once though.
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2015 AT 8:58 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,645 POSTS
How long does it take for the voltage to increase after start-up?

As far as fuel pressure, here is a video to watch.

https://www.2carpros.com/articles/fuel-pump-pressure-and-regulator-test-video-all-cars
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2015 AT 10:49 AM
Tiny
KLIVERGOOD
  • MEMBER
  • 5 POSTS
Takes 3-5 seconds usually for the voltage to jump up and idle to return to normal
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2015 AT 10:52 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,645 POSTS
Does it seem a low idle is causing the voltage increase to be delayed?
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2015 AT 10:58 AM
Tiny
KLIVERGOOD
  • MEMBER
  • 5 POSTS
Not 100% on that one. The voltage it low and it chugs and dies until voltage goes up then will stay running. It did go through a phaze of dying before it downshifted and volts dropped also then.
Was this
answer
helpful?
Yes
No
Tuesday, March 3rd, 2015 AT 12:04 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,645 POSTS
Do me a favor. Take the vehicle to a nationally recognized parts store and have them both load test the battery and check the alt output. Most will do it for free.

To me, it sounds like there is an issue with one of the aforementioned items. If there isn't enough power to the electrical system, all kinds of things will go haywire.
Was this
answer
helpful?
Yes
No
Wednesday, March 4th, 2015 AT 5:19 AM
Tiny
KLIVERGOOD
  • MEMBER
  • 5 POSTS
Had battery and alt checked and both are fine. Now I'm lost on where to go next.
Was this
answer
helpful?
Yes
No
Wednesday, March 4th, 2015 AT 12:49 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,645 POSTS
That's good. Have you had a chance to check the fuel pump pressure? I am trying to eliminate things. Please bear with me.
Was this
answer
helpful?
Yes
No
Thursday, March 5th, 2015 AT 6:33 PM

Please login or register to post a reply.

Sponsored links