2012 mazda 6 – P0172:00-ac and P0172:00-af.

tull_rules

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Make
Mazda
Model
6
Year
2012
Miles
98000
Engine
2.5L
2012 mazda 6 – P0172:00-ac and P0172:00-af. Chk Eng light “system too rich”. Have had tranny flush,replaced-egr/maf/map/air filter, cleaned throttle body. Also have blinking “D” light. Get hesitation/herky jerky at times
 

billr

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OK pros (Nick, Dan, Dave, GRC), I have lured this one over from TroubleCodes. Now strut your stuff and show how helpful we can be here!

PS: I expect one of the first tests they will want is reading fuel pressure, with a gauge.

PPS: confirm it is P0172 and not P0171 (P0171 was mentioned in the TroubleCodes comment).
 
Last edited:

tull_rules

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Thank you everyone in advance. I am not very knowledgeable but I am starting to learn. I welcome any suggestions
 

billr

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Are you confirming there is only the P0172, no P0171?
 

grcauto

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Regardless it's a fuel code whether lean or rich we want the fuel pressure.
Do you have a gauge and know how to do it?
 

billr

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No tools at all, not a DIYer? Who changed all those parts, a friend or shop? Do you want to become a DIYer? If not, we will still try to help you learn enough to not be "helpless" when dealing with a shop; but the nature and scope of our questions will change. Any competent shop should need little tech help.

If you do want to check fuel pressure, then a FLAPS (Friendly Local Auto Parts Store) will loan/rent the gauge. Now I gotta check to see if this engine is GDI...
 

nickb2

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Also have blinking “D” light.
This a problem. Mazda uses ford algorithm.

I am only going on what you wrote.
ranny flush,replaced-egr/maf/map/air filter, cleaned throttle body. Also have blinking “D” light. Get hesitation/herky jerky at times
Stop throwing parts at car and suspect vacuum leak.
 

nickb2

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Hint, these mazda jobs like breaking the inlet air tube. Look for crack there after MAF sensor.

A crack there will give all the symptoms you have.

Now, you are chasing a rich AND lean code. Sherlock holmes theory applies here. You CaNNOT BE RICH AND LEAN at same time

@billr, I notice you are being carefull. The 2.5l mazda was not a gdi.

;)
 

billr

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Nick, why are you saying lean? I may have confused things there. The OP is only reporting P0172.

Are you sure about the no GDI? My brief research indicates some 2.5 engines in that car were GDI.
 

nickb2

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Also, do not over look PVC valve. it will collapse, I hope I wrote that word right.

I have seen multiple time, under intake, the short hose that goes there will deteriorate. This also creates multiple codes.

Since you have a forscan, it SHOULD have live data, unless it is just a code reader. For that, I can only show in PM how to access that.
 

nickb2

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yes, you are right, just rich code, sorry, typing too fast. still goes to what I am saying,

QA for this guy, does he hear a whistling sound at idle?

I know for a fact, these japan jobs love intake vac leaks on cyl #1 close to alt, and pvc hose also. metered air is essential for these japan jobs.

,
 
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