I repent!

Is there any hope!? There’s sludge and no free flow of oil in the 2003 Honda Civic. Two places owned by the same company offered differing recommendations. The first, advised against being on the road long and possibly selling the car for parts. The second place referred me to a service station for cleaning and flushing out the engine. Obviously, a new car is not an option, but if another car is needed-how long would I have? And, what’s the current dangers and lastly-is there any hope, or will this be throwing good money after bad-or further endanger/jeopardize the engine? Thank you for your time and suggestions.


I’m going with no hope. Generally, if the sludge is that bad, everything just needs to be disassembled and cleaned. Not only is it unlikely/impossible that sludge of that magnitude can be cleaned by a “flushing,” but a lot of what the flushing would accomplish would just be to dislodge more chunks of it which will continue to clog everything up. Then, on top of that, you have the damage already done to the engine from lack of proper oil circulation. In other words - that engine is now highly contaminated scrap metal.

You could just look for a used salvage yard engine - and then start getting your oil changed according to schedule. But then the question becomes, what else on the car has been this neglected? Everything? Selling it for parts is probably your best bet.

I’m a professional mechanic. If I opened a valve cover and saw that I’d close it back up. I would price out a rebuilt engine and a used exchange engine. If neither of those are an option I would advise you to get towing/roadside insurance and tell you to drive it until it died, saving money for another car in the meantime.

There’s no treatment short of a complete rebuild that will save that engine.

I agree with @cigroller‌. No hope. That’s bad bad. If you get a salvage engine, try to get it local and have it checked that it’s not in this condition. Selling for parts will take some time and probably little money for your effort. Salvage yards around here sell cars. If that’s your case, see what they’ll do with you trading it in.

When an engine is that sludged up, this is the only method to remove the sludge.



Your sins are forgiven but you still must pay penance my son. Several thousand dollars worth.

Hopefully though others will learn from your experience.

Just how far do you go between oil changes? Have you ever changed the oil?

If the engine is still running OK, I would clean out the drain back holes so that oil can get back to the pan, then put on a new valve cover gasket kit and assemble. Then put in cheap 10w30 oil and a new oil filter and drive it till it drops. I’d change the oil about every 1500 miles for awhile, then every 3000 if it lasts a year.

Basically get every last mile you can out of it. BTW, I have seen engines that look like that last quite a long time with just frequent oil changes for a while. GM engines made after 1975 would sludge up like that on 10w40 oil very quickly. As long as the oil can drain back, you’re good top go.

It’s toast in my opinion and should not be taken any further than a mild walking distance from the house.

@repentant, just for interest, how did the engine get so badly sludged? What are/were your driving habits and oil change (in)frequency? So we all will know what not to do. :wink:

I agree it’s probably toast…but you can TRY to remove it chemically…but I don’t think it’ll work on something that bad.

Your next oil change…replace one quart of oil with a quart of Rislone. Change oil (with filter) every 1k miles doing this process for probably 20+ oil changes. You may still end up putting a rebuilt/used engine anyways.

If the oil is changed regularly and kept topped off the engine might last many more miles but it I wouldn’t get too far from home.

I would try using a chemical flush, maybe a few times in quick succession with cheap store brand oil. It couldn’t hurt to try.

First, I’d buy three of the cheapest oil filters I can find and one good oil filter. I’d also buy three cans of engine flush. Read the instructions carefully. The one time I used a chemical engine flush, the instructions said to run the engine for five or ten minutes with the flush in it, but don’t drive while the chemicals are in the engine. Once you have your supplies:

  1. Drain out as much oil as you can.
  2. Replace the oil filter.
  3. Add two or three quarts of fresh oil to the engine.
  4. Run the engine for a couple minutes and then shut off the engine.
  5. Add a can of engine flush to the engine and let it idle as long as the instructions recommend.
  6. Shot off the engine, drain the oil and change the oil filter.
  7. Repeat steps 3-6 two more times.
  8. Fill the engine with the correct amount of oil (about 4 quarts I think, but check your owner’s manual for the proper capacity) and see how it does.
  9. You might consider changing the oil and filter one more time to get out any lingering engine flush chemicals.

Keep in mind engine flush is a harsh solvent with lots of warnings on the label, so be careful about getting the contaminated oil/engine flush mixture on yourself. Also make sure you have a few good crush washers on hand for the drain plug. Read the label carefully at the store before you decide to begin a project like this and follow the instructions to the letter.

DISCLAIMER: What I am proposing could potentially do serious harm to your engine, so I only recommend this as a last resort. If you find that after one or two flushes things look pretty clean when you peer through the oil fill hole, you might stop at that point.

What led you to have the valve cover pulled, oil light? Horrible noises? Both? If the oil pressure never dropped low enough to trip the light, you may get some life out of the motor with one of the flushes already recommended.

@‌ Whitey
I like your suggestion but if you believe that somebody will go through these steps after not checking, replacing the oil at recommended intervals - hence the sludge - then you are one of the most optimistic person on this board.
Thank you, I wish I can be just like you.

Like NYBo, I have to feel that the engine has issues which led to it being in the shop in the first place and having the valve cover removed.

That pic shows a prime example of what an extended oil change regimen leads to. I’ve seen a lot of sub-40 and 50k miles engines that looked just like that and a few of them even worse.

I don’t like the chemical flush on an engine like this. Problem with that…is that it may dislodge large chunks of oil that could clog the filter or worse the oil pickup.

Even with regular maintenance an engine can get badly gummed up. I bought a ‘ticking’ Plymouth for $100 and found that non detergent oil had been used. The valve covers were loaded with pasty sludge.

A flush isn’t going to work on an engine that’s already plugged up because the fluid can’t circulate. The OP indicated it’s in the shop because it’s plugged up. It has to be taken apart and soaked along with mechanical removal. If it’s been run dry due to being plugged up, it’s probably not worth the time and effort.

That link showed an engine with ~8k miles on it that looked similar to the OP’s. Even though that one had the original filter still installed and therefore surmised it was also the original oil, I’d be hard pressed to describe that as being completely due to an “extended” change interval. Some engine designs can take much more abuse than that and not look that bad. I think the sludging result is highly dependent on the engine design, not just the maintenance record…

It could be plugged up because the oil drains are plugged and all the oil gets trapped under the valve cover. But I would not use a chemical flush either. Just a light (5w30) detergent oil with frequent changes for awhile after clearing out the oil drains.