2006 LR3 103k miles, Manifold leak? This a minor sound I can hear when engine is just started and cold. A soft puff of sound, no smoke or oil leaks. Nearly completely gone when at normal temp. Bothers the heck of of me thinking it may get worse. Possible a head or manifold bolt has stretched and lost torque?

Last, only when cold, Florida cold, sometimes I can also hear a squeak... Only hear similar on other make cars for belt or going bad water pump. Any ideas?

 

Wouldn't you get a lean P171 or P174 depending on the side since extra O2 is introduced before the O2 sensors.

 

Great point!!!! I had that code about 3mo ago and just got a check engine light..... bet you called it. Heck, Ill check now. Let you know. Thanks

 

Although have GAP with VIN for LR3, used my old OBII scanner to read then clear

2006 LR3
codes
PO 172 System to rich bank 1
PO 175 System to rich bank 2

I cleared and all ok. Well sorta.... guess is stressed and stretch manifold bolt(s). Similar happened to Shelby during a race the first year of the GT40
Think diagnose correct?
Fix 1 Pull off and torque new bolts w/ new gasket
Fix 2 Pull one bolt at a time and replace new to correct torque

 

First time bake 1 and 2.... thats both sides I think
had code through bank 1 3to6 months ago

 

Hey, see some from Lucky8
Just bought GAP and more there.... Great customer service. Recommend buy there

 

Used GAP today for first time on LR3. Showed codes again bank 1 and 2 running rich... Will need to run the easy stuff first, but I think that slight 'wisp' sound when first start cold and there till at normal running temp is related

 

Did you ever find out what the puff sound was? I have the exactly same problem