Super appreciate all your responses!! Will have to wait on flushing until next week, planning to bring to Bauer likely. If we find a cracked head only, I'll likely send to Hoffman

Send good vibes my way please!!

 

Alright, just over a month later and my car is getting put back together. Long story short, looks like it was just a bad oil cooler! The car is in the final stages of repair and testing, and then we'll be back on the road, no new engine needed after all!

Absolute best case scenario.

 

Awesome news! Congrats. Now go buy a lotto ticket. 😁

 

Great news !! I love to see a serious problem fixed with a frugal repair !!

 

 

That was awesome to read. I am tackling an intermix issue on my '99 c4 and recently changed the oil cooler + air oil separator as a first attempt fix. There is no coolant in oil, only oil in coolant. I am located in a country devoid of Shout so waiting for it to be imported before I flush it with it. Ran water through the cooling system only so far, but theres still ample sludge in the coolant reservoir.
Question: Is it okay to point a pressure washer gun into the water pump hose to quickly flush the entire system (minus the heater core)?

 

I wouldnt put any more then household pressure through the system. U can damage the rads

 

Congrats!

 

Happy to read this. Good for you. I was actually going to comment this. I don't know why everyone automatically jumps to the absolute worst case scenario. Not only is the oil cooler the best case, it is also the overwhelmingly most common case when intermix happens. Very rarely is it a cracked head, and when it is, usually as a result of overheating the car. Glad you avoided that.

 

Might just be left-over oil in the system. The coolant system has a lot more places where residual oil can cling to all the little passages and coolers/heat exchanges. I wouldn't put high pressure through the system. You are looking for volume of water, not pressure. just keep flushing it and eventually it will all clean itself out. You might find that after it looks clean and you start driving the car, some residual will still pop back up within a few days/weeks. You may have to fill, drive and flush a few more times before it is totally clean.

 

It's because the Y2K Syndrome is real ....The early 3.4 engines are very susceptible to head cracks. The head gaskets NEVER blow, the oil coolers rarely fail , the AOS causing intermix is also rare but happens, over the years we have found that heads cracks are the #1 leading cause of intermix on the 3.4 by a margin of about 10 to 1..

There is nothing wrong with testing the AOS or oil cooler for internal cracks that can cause intermix, and I commend your for it , and it "should" be done before jumping in to a head repair, but you will get tired of recommending that when it will be a waist 9 times out of 10...

 

... and cylinders crack...