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mo problems (i think i know)

  • Thread starter Thread starter Mr. Rustypwnz
  • Start date Start date Apr 17, 2010

Mr. Rustypwnz

Advanced Member
Jun 1, 2005
1,761
63
69
indianapolis/ valdosta ga
Apr 17, 2010
#1
  • Apr 17, 2010
  • #1
ok guys i recently got my new pi 4.6 into my 98gt, started fine and all, but now has developed this hit or miss, miss.. when i start it up in the morning its fine until about 5 miles, then it will idle like it has massive cams, and be really lagging in the lower rpms, like you have to go to wot like clearing out a carb of something. i pulled codes, im getting a p0133, sensor 1 bank one rich condition. it smells like gas when driving, pretty bad, im also getting a MAF code, but i swapped those out tonight with a new remand unit. it feels the same!! but thats all the codes im getting, i thought that an o2 sensor wouldnt cause driveability probs? i know a maf will, but this has me going crazy.. will an exhaust leak do this? i know there is a possibility of a leak on the drivers side, however i cannot hear one..

btw it went through about almost a half a tank in ~70 miles, not 200 like it was


plz halp if possible, or else it gets a vic jr. and a 650..
 

Mr. Rustypwnz

Advanced Member
Jun 1, 2005
1,761
63
69
indianapolis/ valdosta ga
Apr 17, 2010
#2
  • Apr 17, 2010
  • #2
the tach also will jump around a bit when it happens? ground?
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Apr 17, 2010
#3
  • Apr 17, 2010
  • #3
Check the fuel pressure. Get a gauge on it and monitor it as you drive. See what it does when the engine starts mis-behaving.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Apr 17, 2010
#4
  • Apr 17, 2010
  • #4
exhaust leaks causes rich condition

Bank 1 sensor 1 is on the RIGHT side before cat side. And yes they can cause driveabilty issues. You must be confusing bank 1 sensor 2 as it is behind the cats and will not cause driveability issues.

An exhaust leak CAN cause a DTC. The leak allows unmetered air to enter the exhaust and make the PCM THINK the engine lean. This causes the PCM to ADD fuel in response. Hence the fuel smell.
 
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