Rustyrock

Around 2 weeks ago, I noticed rough idle when started, then seemed to settle. Soon after it threw a bunch of codes (Sh-Awd, cylinder 3 0303...). I’ve had a cylinder issue previously so assumed it was a coil again. Went to put it in and noticed coolant in rad was low, although overflow was ok.Changed plugs at this time as well. Replaced cap and a few minutes later, gurgling, and the overflow sucked into the rad. I thought maybe air, so ran with rad cap off added more coolant and changed coil. Drove around the block (it drove fine) and my coolant temp started to spike. Parked in driveway, no leaks, trans fluid is good. Decided to go get gas, temp spiked again very quickly, I pulled over and it cooled quick and stabilized as I drove home (was only a few minutes). Checked oil at home and noticed it was high, but thought my son had just overfilled it. Moved the car in the driveway a few days ago, rough idle, codes thrown. Then had to move it again, wouldn’t crank. Checked oil, noticed it was watery...so that’s where the coolant was going.

Since then, I’ve drained the coolant (it’s clean, no oil), drained oil (yes coolant in oil) and added new oil and filter. I’ve turned the engine by hand and it still turns so not seized. Removed plugs and squirted a bit of oil into the cylinders. Interestingly, three plugs were fine, but #3 was fouled, and I had just replaced all about a week ago.

So, thoughts on what to do? I’m assuming head gasket, but wouldn’t know until it’s pulled apart. I can do basic engine repairs (change components and such) but never something like this. The car is in great shape, should I get a shop to look at it, or is it probably damaged too much inside? I have the service manual, just not much information online about doing this repair for this vehicle.

Altair

Welcome Rustyrock!

another member had a blown gasket, fixed it on the cheap, no replacement required:

https://acurazine.com/forums/1g-rdx-.../#post16504864

msg 17, your case may be different.

Btw, driving without the cap on virtually guarantees boiling coolant around the hottest areas of the engine around 212F probably within 2 minutes from cold start, in turn resulting steam creates uncooled engine pockets. If the system could hold the pressure, temperature would have to rise much higher before the same. Try to limit such driving time to 1 minute or less.

Good luck and let us know when situation changes

Rustyrock

Thanks for the reply. The only time I had the cap off the rad was when I had it idling in the driveway initially as I thought there was air in the coolant lines. After my rad drain and oil change, it hasn’t been driven until I figure out what to do. The fact that only one cylinder plug was fouled is interesting, but I’m not sure if I can determine anything from that. I’m leaning getting it towed to a shop to take the head off to see where the problem is.

CSmoney28

Try to check the tune the car is running and if you see any inconsistencies.