How to do a piston soak correctly?

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2001 Corolla. Have had it for about a year, but it was consuming oil at a ferocious rate: first 1 quart/400 miles, finally all four quarts/200 miles. Now, a dead cylinder #4, and the likely death of the car. Never had the resources to to do an engine rebuild, unfortunately.

In the hope that cylinder 4's problem is simply a stuck ring and not structural damage, I'm going to attempt a piston soak.

How much solvent to use? Enough so that the fluid goes over the top of the piston head? Will turning the ignition be enough to extract all the solvent after the soak, or do I have to find some kind of syringe to get the rest out? Leave the spark plugs loosely in the cylinder during the soak (and then remove them during extraction)?
 
Done many soaks on Corollas; fill the cylinders as much as possible. Turn the engine over with a ratchet every few hours, and YES, use a syringe with a long piece of aquarium tubing to suck out remaining fluid. Leave the plugs out.

I would use B12 Chemtool; it's the only product that made a noticeable difference in my Corolla.

After the product has been sucked out of each cylinder, I would fill the syringe with a small mount of oil, stick the hose back in each cylinder and squirt the cylinder walls. That will help build compression when you try and start the engine back up.
 
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Originally Posted By: Lubener
I would change the plugs afterwards.

And the oil. If possible do it when a spark plug change and oil change are due, and kill three birds with one stone.
 
I tried the induction method as per some Youtube videos for some other (non-Corolla) cars, but the engine instantly stalls when any of the vacuum lines are removed.
 
Originally Posted By: Drew99GT
Done many soaks on Corollas; fill the cylinders as much as possible. Turn the engine over with a ratchet every few hours, and YES, use a syringe with a long piece of aquarium tubing to suck out remaining fluid. Leave the plugs out.

I would use B12 Chemtool; it's the only product that made a noticeable difference in my Corolla.

After the product has been sucked out of each cylinder, I would fill the syringe with a small mount of oil, stick the hose back in each cylinder and squirt the cylinder walls. That will help build compression when you try and start the engine back up.

Thanks, will try that. Somebody over on a Saturn forum has an old piston soaking thread, but he says to use stuffed rags in the cylinders, and for some reason he says to keep them stuffed even when turning the engine. But I can't figure out why; wouldn't that prevent the solvent from escaping the cylinder?
 
Originally Posted By: demarpaint
Originally Posted By: Lubener
I would change the plugs afterwards.

And the oil. If possible do it when a spark plug change and oil change are due, and kill three birds with one stone.

My problem might be too bad for that. The cylinder died when I tried to make it up a steep hill, which pretty much shut the engine off at the time -- but I had just filled the crankcase with 4 quarts the night before and there was oil in the engine. I managed to get the engine going just long enough to get it to a parts store, and installed new plugs right in their parking lot, but it made no difference and there looks to be oil and perhaps even coolant on the threads of the new plugs. The constant oil burning for the past year has caused repeated misfires and maybe damaged the cat (hopefully not). I can top more oil in the crankcase, but it would basically be just new oil that would be drained if an oil change was done. Check engine light is now flashing while driving and the engine is gasping and trying to stall. I'm half-worried that there might now be fuel in the cylinders and could cause an engine fire, but maybe I'm just being paranoid (or that I just don't know much about cars.)

After the soak, should I try to use some plug spacers to prevent fouling?
 
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Originally Posted By: marantz_fan
2001 Corolla. Have had it for about a year, but it was consuming oil at a ferocious rate: first 1 quart/400 miles, finally all four quarts/200 miles. Now, a dead cylinder #4, and the likely death of the car.


Sorry to say but 4 quarts 200 miles, I doubt a piston soak will help.
I would think there's some bigger issues there.
 
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Originally Posted By: gathermewool

What are the DTC's for the flashing CEL? Is it only for cylinder 4 misfire?

Compression? Leakdown?


My local shop said the compression for the other three cylinders were more or less ok, but that #4 was 50. They didn't tell me what the latest scan revealed, but for most of the past year a constant check engine light was for various misfires on some or all of the cylinders.
 
That'll do it - no need to check codes - it's very likely misfire. I'd be very careful driving it, if you intend on getting it fixed. You could kill the cat if this thing is dumping a lot of partially-burnt hydrocarbons into the exhaust.

Originally Posted By: Drew99GT
Have them do a leakdown test and see where the cylinder is leaking from. Has it been consuming antifreeze recently?


+1 - not sure why your local shop wouldn't have done a leak-down test, as well, after finding only 50# of compression in one cylinder. If you have a bad valve and not through to the crank case, then you'll (mostly - not 100% definitively) have your answer about whether a piston soak will work (i.e., likely not).
 
I haven't done the piston soak, but have decided to get the car junked sometime this week. They'll give me $200 and get it towed, yippee. But I have to get it out of here, unfortunately. Car is posted on Craiglist in my area, but no attention except from scammers. A shame, because with a new/rebuilt engine this car could last many more years. My "new" car is a 2008 Nissan Sentra which had better not let me down.
cry.gif
 
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