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vaccuum leaks and hoses

coopab

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Trying to solve P0171 and P0174. Sometime I get one, sometimes the other, sometimes BOTH. Waiting to see the results of cleaning my MAF sensor I was reading some old threads on these codes. My 99 Ranger is OHV and another thread discussing vaccuum leak in a PCV hose dealt with an '02 (SOHC). Here's a picture of the driver's side rear of my motor. #1 goes to the PCV valve just below and out of sight in this pic. #2 goes to the brake booster. #3 appears to split into two hoses that are wrapped in a protective coil. Question is where do they go? Are they a likely source of P0171 or P0174 issues?
 


JOSEPH169

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take some intake or carb cleaner and spray it on all the vac hose to see if the idle changes and also spray the intake manifolds gaskets to see if they're good too. Also make sure you don't have an exhaust leak.
 

adsm08

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I assume you have a scanner if you are pulling codes.

If it does live data pull up the long and short fuel trims. Write down the idle readings for long and short 1 and long and short 2 in two different columns. Add them, bank 1 to bank 1, bank 2 to 2.

Now take the same readings at 2500 RPM and do the same math. A change of less than 15 means that you do NOT have an unmetered air leak.
 

Dune Runner

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A while back I was getting those codes. Ended up being the vent line coming off the top of the fuel tank had come loose. When the charcoal cannister would purge I would get the code. It was sucking fresh air into the intake and causing the lean mixture. It took me forever to find it.
 

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