The engine runs but has an internal knock? Suggest you proceed with caution! Had persons investigating knocking noises on this engine model and end up with a totally trashed engine from continued operation.

Unless a major leak, assume if the IAC valve was leaking coolant it would be sucked into the engine, vaporized and then go out the tail pipe. No sure how this coolant would make its way into the bottom end of the engine. Suppose once the engine was off, coolant still under pressure could continue to be forced into the intake and into the engine cylinders. However would assume you'd notice issues at start up with having coolant in the cylinders such in having a lot of water vapor out the tail pipe at engine start up or even hydraulic lock of the piston from too much coolant.

Any chance of a failed head gasket? You can pressure test the engines coolant system and or conduct something called a block test. The block test checks for exhaust gasses in the coolant via a change in a chemical color. Auto parts stores should sell a block test kit.

Coolant in the engine oil can quickly damage bearings. The oil tends to look like whipped creme or a milkshake.

If a rod or bearing issue the noise may only appear when said bearing(s) are under load. This means when the cylinder is working.(firing). A rod knock tends to appear after releasing the throttle after engine rev. Can try removing ign spark to the cylinders one at a time to determine if the noise goes away.

The engine has two rotating balance shafts below the crank. The gears for the shafts are made of a type of fiber material (they are not metal). Has happened the gear teeth fail and the result is knocking.

Get a section of rubber hose to use as a stethoscope. Then try to locate the area of the noise. The front of the engine (passengers side) has the timing belt, water and oil pumps.

But before doing anything suggesting trying the firing pan or heated spoon test on the oil. Coolant will boil at a lower temp then motor oil. Compare a test of boiling 100% oil, a test of boiling whatever coolant mix you use to a test of what oil you have in the engine. The compare the results of the tests.

Would also consider getting a oil analysis done by say Blackstone. They state a coolant test is $40.

A yes or no for coolant will allow to you make a better decision on what to do next. If coolant in engine, then yes your bearings could have issues. If so and you want to keep the car then better to have at doing engine repair now then continue operation and risk major damage and needing a replacement engine.

 

Thanks for the glimpse of hope Toyomoho
I did a compression test and the results are as follows - 140, 145, 150, 155
I did have a little trouble with threading the compression gauge into cyl 4, spark plug goes in no problem however

I also did a pressure test of coolant system - pumped up to 13 psi and pressure held fine, maybe dropped 1 psi after a half hour

Im thinking I cant do the block test since the engine needs to run and warm up - at this point I feel the engine will blow if I attempt to run it for any length of time.

I didnt boil the oil or coolant - I am pretty sure the 2 have mixed. When wiping the dipstick on paper towel it seems to spread like water & oil not just oil and it definitely smells burnt. I have to assume when I got the new cap my coolant loss slowed way down but was still leaking through my IAC valve. But the added pressure to the IAC valve gasket accelerated its failure. I definitely had green coolant in the TB and now it appears to be the milky white substance you referred to. And I think you are correct - while I waited for AAA to come the coolant must have expanded through the IAC and into the throttle body. And starting it a few times and cranking it a few times has probably made things worse although there are no major leaks of oil or coolant anywhere.

So do you think I threw a rod or do you think the bearings are being starved of oil? Can you clean a mess like this?
If my engine went into hydraulic lock would it still crank? If bearings can knock - does this mean an engine tear down? Not sure I can do that but obviously nothing to lose at this point so willing to try.

Can the knocking sound be from bearings being starved of oil or do you think its from a bent rod?

If this sounds like the car is done and I have to start looking for another camry I would like to stay with the 2.2L engine, years 92 to 01.
Do you recommend any that are good or to stay away from. I like the 95, I have had good luck with it.
If the car is going to be scraped could I salvage some parts off the engine like TB, radiator, DIST, airbox, timing components & WP, ALT, ???
Anything else you can think of worth keeping - some are fairly new. Will these interchange into any 2.2L with federal emissions or would I need to stick to a few specific years?

Thanks
Kevin

 

Don't know for sure what the issue is with the engine.

If you have enough coolant in the oil it wipes out the bearings. Its not staving for oil as in a lack of flow but the coolant breaks down the oil lubrication properties as in a lack of lubrication. Your knock can be from now bad bearings.

The compression is OK and even.

Hydraulic lock would cause the engine not to turn over and could damage a rod as the piston would be trying to compress a fluid..

The 95 California engine is different from the federal engine of the same year. Can't remember the differences. It has a different head and maybe compression ratio. The head has an air intake port on the center back of the head. Different injectors, IAC, computer.

You can check part numbers at online Toyota dealers and sites such Rockauto for Fed versus California models.

Thought Toyota changed the gear tooth count for the balance shaft and crank gear that drives them around 1994. This crank gear is integral to the crank.

As recall after 1995, the engine had ignitions changes that eventually eliminated the distributor. Toyota added a crank sensor in 1996 then later crank/cam sensors (perhaps in 1997 and eliminated distributor). Years 97-99 appear the same. 2000 had some intake system changes. 2001 apparently was changed to meet California emissions standards (only one 4-cyl engine type offered but it meets California specs).

If you have the time suggest taking the engine apart to determine what the problem is.

Some folks had good luck with used imported engines from Japan or US auto salvage yards. Note you may need to swap some external parts and sensors from your old engine. There are also rebuilt engines offered (search internet).

Most owners opt for a used engine engine to save money and LOTS of owners have done this..

My 2 cents is if you like the car and want to keep it, might consider rebuilding the engine if its not damaged beyond repair and you can do it DIY. Find a decent machine shop that does engine part machining.

Parts are readily available. Can get a rebuild kit for a complete engine, or just bearings, etc. Some machine shops have ties to auto parts outlets and can get everything you need to assemble the engine once any machining is done for a reasonable price. You will spend more money but you will know what you have when done.

Suggest if finding another engine to replace the valve stem seals. These seals harden with time and lack of engine use (the engine sits). The result is blow by at engine startup. Also replace the cam, front/rear crank and oil pump seals as an easy job with engine out of the car.

 

Ive been doing my research on how to proceed with digging into the engine. A couple of questions.
Should I start by simply dropping the oil pan and seeing if i could repair the bearings from that point of view?
I have seen some where if the crank isnt badly scored a few turns of some fine sandpaper can polish it back up. Then replace the bearings.

Also is my gas contaminated now? If coolant was getting into the combustion chamber is there any chance the coolant made its way back to the gas tank via the return line?

Should I pull the valve cover off and see how much sludge is in the camshaft area? I did see some gooey white stuff getting shot into the throttle body when I was trying to determine if a rod was bent. All cylinders sounded the same making me think definitely a shot bearing(s).
Thanks

 

Doubt the gas is contaminated. The fuel pump operates the fuel system at a higher pressure then the coolant system pressure.

Has happened on some engines that sludge blocks up the block oil passages. Removing the valve cover is a common way to check for sludge.

If you think its bearing suggest removing the engine for better access. Get some kind of engine stand to allow rotating the engine 360 degrees for easier access.

To get to the bearings requires taking off the balance shafts.

Before taking the engine apart read up in detail on this. You want to keep all the parts organized when removing them to put them back in the same location.

The balance shaft may shims to get the proper axial clearance and you want to reinstall these as they came out.

If you remove the head, keep track of where the valve clearance shims go.

Read up on crank journal inspection for which the internet will have lots of video's,

 

"Im surprised Toyota would use such as poor design." ... Haha, your '95 camry has outlasted more than most could hope to dream of. That's almost 25 years.

If you're still on the fence as to how or where this 'coolant on your TB' is coming from, have you considered the breather hose? Especially in cold weather the engine will accumulate more moisture than normal and especially on a cold engine, the oil will look creamy/pasty colored on the dipstick. Often times, if it's not your IAC leaking, this substance can find its way onto your TB from the crankcase through the breather.

Also, since it's super cheap, have you checked your PCV valve? Lots of times that getting clogged can keep it stuck half open and result all sorts of visible oddities in your oil. I suggest if you have that you take that out and thoroughly clean it or replace it for $10.

Although you've already had your engine checked for compression loss, a very easy way to know if you have compression loss is by simply opening the oil filler cap, starting the engine and feeling with your hand over the oil-filler-cap for air moving out. If you cannot feel any air coming out of filler cap, there's no compression loss. Just a quick tip for anyone before you considering buying a compression tester or paying a mechanic to test it for you.

Before replacing anything in your engine you might want to also try some combustion chamber cleaning if you haven't as well as a crankcase flush. For both you can use regular old WD-40. For combustion chamber cleaning, shoot an entire 12-16oz. can of WD-40 through a vacuum line while the engine idles. On my '09 2.4L Camry, I use the EVAP hose (unplug it from canister and shoot the WD40 down the hose) and because the hose enters right at the throttle body, the WD-40 is going to hit every cylinder. If it's the first time you've done this, I would also follow-up with a spray bottle of distilled water. Just spray slowly and pay attention to how the engine sounds while you do it; it's easy to make the engine stall if you go too fast and/or don't keep a good enough seal on the vacuum hose.

For a crankcase flush, wait until your next oil change - or change your own oil. You want to do this just before the oil is changed. You don't want the car to be driven very far with 12-16 oz. of WD-40 in the crankcase because you'll likely burn-off a bearing... Since I take my car in to get the oil changed, I usually do this 2 or 3 times a year in the parking lot 30 minutes before my appointment time. All you do is start the engine, open the oil-filler cap and spray a whole 12-16 oz can of WD-40 into your crank case while the engine idles. Once you've sprayed it all in the crankcase, put the cap back on and then allow the engine to idle an additional 20-30 minutes. When the oil is drained it will take out a lot of carbon gunk and god knows what else that's been stuck or caught in your valves etc that you wouldn't otherwise know was causing any issues.

Just a few very cheap unorthodox methods I suggest you try. My 2009 2.4L camry has 415,000 miles on it with original engine, original transmission and no longer burns oil. It drives like new.

Just my 2cents.