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would the oil temperature sensor also set the PO175 code?
2003 VDP 104,000 miles
2006 XJ8L 84,000 miles Throwing the PO175 code after I replaced my radiator due to it blowing out caused by the auxilary heater going dead which caused ALL the sensors and engine being soaked with antifreeze!! What a mess!
1986 XJSC Cabriolet 56,000 miles (My baby)
Regards: Dennis Cunningham
Yes that is logical, but a comment on the X308 forum from someone who had some work done at a shop said that the shop had broken off a plastic piece of the inlet hose between the MAFS and the TB. They had bodged it up with tape but the tape gave way when the motor was hot leaving a gap which would suck air, and he got P0172/P0175, which went away after he had repaired the hose. ?????
Hi chatherl,
An air leak between the MAFS and TB would cause P0171/P0174 for lean running due to unmetered air being inhaled into the intake. Either the shop or the poster listed the wrong codes for the cause.
would the oil temperature sensor also set the PO175 code?
Hi Dennis,
I don't believe a problem with the oil temperature sensor will trigger P0175, because the oil temperature sensor is neither a primary nor secondary reference for fueling management by the ECM. Here's what the DTC Summaries manual gives as possible causes of P0175. The same possible causes relate to P0171:
Dead thread, but for clarity...P172/P175 means the trim is turned all the way lean, and the mixture is still too RICH. If the mixture were lean, it would trigger P171/P174. So...the codes the OP had are for RICH, and only RICH!
1) The only vacuum leak that could possibly cause this condition is the vacuum line to the ECM. Any other vacuum leak would trigger a lean code. When the OP found vacuum leaks, they were gravy, but did not cause the rich codes, as he verifies.
2) MAF will always be the primary suspect for a dual bank rich condition.
3) Secondary suspects will be the temp sensors (air and coolant), leaking injectors, and fuel pressure regulator.
04-08-2020, 08:27 PM
