2002 Outback 2.5L H4 Auto w/ p0172 CEL code

[Sackett]

Originally Posted by 5bgeorge

I drove the car the 200 mi home and discovered that it was having some trouble idling in Drive...so I'm set to change out the Fuel filter and PCV valve and give it another go...if that doesn't resolve the idle issue, I'll be going back to the dealer for ... another ECM reset?

OK, no more ecm reflashes for you; once you get updated you have the latest upgrade. The idle issue is because of the reflash; your car has forgotten how to idle properly and it will relearn it. This happens whenever you reflash or even reset the check engine light.

[5bgeorge]

Hey CARDOC...thanks for your thoughts...replaced the fuel filter and PCV valve (both overdue and in need of being replaced) and the idle-in-gear problem seems to have evaporated. Runs very well now and CEL has not reappeared. No vacuum lines amiss and have run nearly a quart of Lucas injector cleaner thru it in the last 12,000 mi, so I don't think I have a clogged injector...plus, I am running the highest octane non-ethanol fuel available short of aviation fuel, so I don't think it could be bad gas, all Murphy's aside. I think the Dealer did a pretty great job considering that I was very specific and had some previous data and experience to provide. The mechanic, Doug, definitely knew his way around the 2.5l H4 engine and was very forthcoming regarding the ECM. the code, the symptoms, the fixes I had already attempted and the oil leak.... I will not be surprised if the ECM reprogram fixes the CEL and related symptoms; if not, I at least have a secondary solution to consider, and one that was at the top of the list to begin with. I'll check back here and update the thread if anything changes...plus, I think I may need some suggestions with the access plug leak on the left bank side of the front crankcase. I'm ready to proceed with a timing belt kit/H2O pump service unless someone pops up with a better alternative.... I replaced the timing belt and pump 70k mi ago, so I guess the service is due anyway. What I am wondering is whether I should go ahead and replace the front crank seal, the cam seals, and the access plug washer seals at the same time - or, take the road that suggests 'if it ain't broke...' Thoughts?

[cardoc]

It's not maintenance for nothing. With high mileage, it is always a good idea to replace parts that are readily accessible when performing another service. Changing seals at the same time saves time and money. Same goes with the timing components. A timing belt kit from Gates is available which has the pulleys with it. Replace the thermostat also. It's attached to the pump anyway. Check the interior of the hoses while they are off. If you can rub the inside of the hose with your finger and feel a soft surface or some of the rubber comes off the hose, replace them. The average lifespan of a hose is 7 years.

Not replacing these parts can lead to a failure and potential damage. Why risk it?

[5bgeorge]

Thanks to Sackett & cardoc for the input. For the record, the idle problem post-ecm reflash and upgrade did in fact evaporate and I no longer have any idle problems. however, the CEL has reappeared and I will be getting a replacement A/F sensor along with a timing belt kit (complete with idler pulleys, H20 pump & tensioner), crank and cam seals and access port washer seals. Any other thoughts on things that ought to be included would be appreciated. Am considering getting the FreeSSM diagnostic software (know that I have to buy an access cable) to tap into the ECM & TCM settings...hoping that I will be able to check and reset the CEL once to A/F replacement is in. Am I being crazy?

[cardoc]

Nope. The more you know and understand your car, the better. It gets easier with time and experience as you learn how the electronics operate to control the mechanical along with how the mechanical effects the electronics. It will also help you to understand all us techies when we get overly specific in our explanations.

And you will learn something new everyday. Just pay attention to the car and listen when it cries for help.