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Two lean systems codes and a funny noise...

  • Thread starter Thread starter MyEarsHurt
  • Start date Start date May 27, 2005

MyEarsHurt

New Member
May 21, 2004
918
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0
May 27, 2005
#1
  • May 27, 2005
  • #1
Two lean system codes and a funny noise...

Ok, PI swap is over and 50 miles later, I get a CEL, I check it and I get two codes.

1. System too lean bank 1
2. System too lean bank 2

I have a funny ticking noise on my passenger side, and I am not sure if its an exhaust leak between the header and the midpipe. Would an exhaust leak there cause me to be lean on both banks?

My other theory is this...when I purchased the car, the previous owner said he had a "computer chip" installed. I never had a chance to ask him what kind, and I have never even looked to see what kind. Could an over-the-counter chip (jet or something) cause my car to lean out after the swap?

Any other theories or thoughts are appreciated. Thanks.
 

CanadaStang

New Member
Sep 7, 2003
2,093
1
0
Mb
May 27, 2005
#2
  • May 27, 2005
  • #2
MyEarsHurt said:
Ok, PI swap is over and 50 miles later, I get a CEL, I check it and I get two codes.

1. System too lean bank 1
2. System too lean bank 2

I have a funny ticking noise on my passenger side, and I am not sure if its an exhaust leak between the header and the midpipe. Would an exhaust leak there cause me to be lean on both banks?

My other theory is this...when I purchased the car, the previous owner said he had a "computer chip" installed. I never had a chance to ask him what kind, and I have never even looked to see what kind. Could an over-the-counter chip (jet or something) cause my car to lean out after the swap?

Any other theories or thoughts are appreciated. Thanks.
Click to expand...
Try checking for vacuum leaks, [perhaps between the Maf and throttle body] It's difficult to say if the ticking noise is a different problem,or the same. Try to narrow down where it's coming from, it may just be an
unrelated exhaust leak, which won't give you a PO171 and PO174 but an intake leak will. Also a dirty maf sensor can through those codes.
 

MyEarsHurt

New Member
May 21, 2004
918
0
0
May 27, 2005
#3
  • May 27, 2005
  • #3
CanadaStang said:
Also a dirty maf sensor can through those codes.
Click to expand...


How do you clean your MAF?
 

CanadaStang

New Member
Sep 7, 2003
2,093
1
0
Mb
May 27, 2005
#4
  • May 27, 2005
  • #4
MyEarsHurt said:
How do you clean your MAF?
Click to expand...
MAF sensor.
http://forums.stangnet.com/showthread.php?t=514150&highlight=cleaning+maf+sensor
 
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