Welcome to the Forum, from Cave Creek AZ.

 

Do you do mostly short drives? If so replace your pcv and then run a water trickle into your engine for 30min at 3-4k rpm after a good hard 15min run. Give it a good hard 15min run after that and repeat a few times. Change oil and filter. If it still faults after 4 or 5 of these cycles you're up for new cats and possibly 02 sensors. Most likely they're just fouled. If it's out of warranty I recommend Castrol Edge 10w60 after 100k in these as the pcv and egr get too dirty from blowby and oil consumption fouls plugs and cats.
Cheers,
KiwiScott.

 

Do you do mostly short drives? If so replace your pcv and then run a water trickle into your engine for 30min at 3-4k rpm after a good hard 15min run. Give it a good hard 15min run after that and repeat a few times. Change oil and filter. If it still faults after 4 or 5 of these cycles you're up for new cats and possibly 02 sensors. Most likely they're just fouled. If it's out of warranty I recommend Castrol Edge 10w60 after 100k in these as the pcv and egr get too dirty from blowby and oil consumption fouls plugs and cats.
Cheers,
KiwiScott.

What the heck do you mean "run a water trickle into your engine for 30min " ???

 

Welcome to the forum

 

OK, I'll show that I don't know much, but I have never heard of adding water to the engine. If this is a good thing to do, it would seem better to determine what a "trickle" of water for 30 minutes is equal to. That sounds like a lot of water. That can't be a good thing.

 

Sorry for the slow reply (Covid). Yes I realise it sounds like a recipe for disaster.
I actualitly it's a perfectly effective way to clean piston tops, combustion chambers, exhaust valves, EGR valves and cats. A straw from a wd40 can will only gravity feed a fine trickle. It works best if the engine is hot from a hard drive and kept at temperature during the process by mid rev range. I generally disconnect the duct to the front of the throttle body however some people prefer to introduce the water into the pcv vacuum tube directly into the intake plenum post throttle body.

In a hot engine, at mid revs there is no risk of hydrolock. It's best to increase time rather than water flow rate to improve results. This can be done as many times as it takes to get the job done as long as you take it for a good hard run between 30 minute cycles and keep it at temperature for the duration of the cleaning. Take it for a drive to finish and the change the oil and filter. You'll be happy to see there will be no moisture at all in the oil.

In your case this will steam clean your cats and remaining o2 sensors making them more efficient and increasing the difference in signal pre to post cat o2 which is more than likely what needs to happen to clear your fault.

Cheers,
KiwiScott

 

How many miles on engine and when was it last tuned up? A miss fire or fuel mixture issue, is the usual culprit causing cats to go bad. Cats are expensive, and you will ruin new ones quickly if you don't fix the cause first.

 

I'm surprised that nobody else besides Bob made any questioning comments about this recommendation. I am certain that I would not follow the suggestion. It goes along with adding sugar to the gas tank because gasoline tastes bad.

 

That's okay, I can say from experience that this does an excellent job of cleaning combustion and exhaust/cats/o2sensors internals, and when done correctly it's perfectly safe. The key is patients, engine temperature maintained and low controlled water flow rate.

 

Like using seafoam. I haven't dripped water into an engine "carbureted" in almost 40 years, it was used to remove carbon from the tops of the pistons and combustion chambers. You can do damage if too much water is ingested though. Also you need to change the oil after, because some will get by rings and into the crankcase. That was my experience. We used to have leaded gas back then also. Remember some of our members are from other countries and all have different levels of experience. For most on here, and I've been on here for a decade, I would say don't do it. I don't like the seaform products and the like "mechanic in a can" while others swear by them, I polished crank journals with emery paper and a shoelace, when I spun a bearing, and changed rings and pistons with the engine in the vehicle. That's old school and it still works. Now here, "usa" for the most part, we throw fixable engines away and mail order a new one. All opinions on here and no one intends harm. As always, peace. .

 

Thanks, for the record I would never do it how is shown in this video.

 

I have "steamed cleaned" engine internals by sucking water in through a vacuum port in the past. and seafoam and other such things. people have been using water injection on cars for years....many boosted LS applications inject methanol/water mix(windshield washer fluid) to run cooler intake air temps. Porche is working on a factory water injection system for turbo cars as well. water is only really bad if you suck in way too much and 'hydrolock' it.

 

Yip, most horror stories are either not true or the water has been applied to a manifold vacuum rather than ported vacuum so they draw more when idling then cool down and hydrolock. Venturies need to be ported vacuum or velocity induced vacuum only. Injection can be run from an existing injector both these options ensure flow only when needed and avoid cool idle with water accumulation.
Cheers,
KiwiScott

 

These codes are commonly caused by cracked exhaust manifolds. This is a common problem on the 3.8L engine. Pull the heat shields off the exhaust manifolds an look for cracks.

I had both codes on my 2009 and both manifolds were cracked. Pulled the front fenders and the manifolds were easy to get at to replace. After the new manifolds the codes are gone.

 

These codes are commonly caused by cracked exhaust manifolds. This is a common problem on the 3.8L engine. Pull the heat shields off the exhaust manifolds an look for cracks.

I had both codes on my 2009 and both manifolds were cracked. Pulled the front fenders and the manifolds were easy to get at to replace. After the new manifolds the codes are gone.

I completely agree.

 

It can be caused by an upstream crack or hole in the exhaust. Yookdew hit that on the head. It can certainly be the cats. A good mechanic who diagnoses problems before throwing parts at a problem will be able to figure it out and show you the data that shows what it is.

 

Well, thanks for the info. I never would have thought.