Ps - Smoke From Atf And Now Power Loss

[greatwhiteshark]

First timer here.

First thanks to this community for getting me this far. I learned alot just reading more posts than i can remember.

I have a 94 ls400. Bought it 3 years ago with no issues. about 2 years ago the dash lights would flash on and off in the winter until the car got warm but i lived with it.

8 months ago power steering fluid started leaking. I was sure it was not leaking on the alternator but could not find the leak and could not afford to fix it. so i ran it with no fluid in the system for 6 months an developed popeye forearms.

3 weeks ago I find the leak in a hose running in front of the radiator and took it off and replaced the hose.

Filled system, worked out the air and no leaks. Then started to notice the infamous smoke out the tail pipe and assumed just a coincidence that it started burning oil at the same time the PS was finely fixed.

then started having to add ps fluid again but no leaks anywhere.

I probably put in 5 quarts of dex/merc ATF in the system between replacing the hose to seal up the PS system and when I learned of the issue with a bad air control valve. This faulty was sending ATF back into the engine. So I stopped filling it.

I ran the car 3 days a total of 45 miles without adding any fluid. Aside from working on my popeye forearms again to turn the steering wheel, all was well.

By well i mean car was running smooth as silk just tuff to turn the wheel.

This morning i started it up and it was rough feeling and sounding engine and exhaust especially from under the mid section of the car. very little power. hard to get it to go 45-50 mile an hour.

Could all that ATF going into the engine be sitting in the catalytic converters and causing some exhaust flow or compression issues? any ideas before i put the the new air control valve on?

[curiousB]

The PS pump has a valve called the air assist value. It is connected to the intake manifold via a rubber hose. The purpose of the value is to assist in steering at low rpms (ie parking). This valve commonly fails and the PS fluid leaks by it and gets into the rubber pipe, onto the intake manifold, then engine. Thats where the smoke comes from.

Search this forum. You can fix it many ways. One is to buy a new valve on put on the pump. Another if to just plug the hoses. And even other ideas of making a plug to replace the value with. Many options some will cost you nothing more than a golf tee.

Good luck.

[greatwhiteshark]

Thank Guru member,

I think i am no on top of the air control valve. As i said in the end of my post, now i have a new problem and am trying to figure out why i suddenly have this big loss of power. I am guessing at at in the end of my post but looking to see if anyone has any experience with this. Thanks for your response. perhaps i should find a way to be more clear about the fact that i have figured out the ATF loss issue but now have a power loss issue.

Again thanks.

[greatwhiteshark]

Dear CuriousB,

Do u think the power loss and rough/loud exhaust is due to large amounts of ATF building up in the CAT's?

Best

[curiousB]

Dear CuriousB,

Do u think the power loss and rough/loud exhaust is due to large amounts of ATF building up in the CAT's?

Best

I doubt ATF is it. Maybe but I'd run down some of the more likely theories first. Since the effect has happened fairly quickly for you I would look to more basic problems first in fuel and ignition.

Go for a 10 mile highway drive at dusk and then stop off the road in a parking lot and take a look in the engine bay to see if either of the catalytic converters is glowing red hot (this is why to do it at night). A red hot cat means unburned fuel getting through and could point to ignition problems on one bank. Very common problem for these cars.

Dirty throttle body and/or dirty/sticky IACV will result in rough running at idle but won't be an issue once the throttle is opened up. Since you mention problems of power loss then I assume it isn't an idle only issue.

Could also be a problem of fuel starvation caused by a worn out fuel pump (replace) or dirty fuel filter (replace). This would be most noticeable at heavy engine loads when the fuel can't keep up with engine demand.

Could also be faulty MAF not properly detecting air flow. There are MAF cleaner solutions you can try to get any caked contaminants off of the MAF wires.

You haven't mentioned if the CEL is on or any related codes. I assume you don't have a CEL lit up right?

[greatwhiteshark]

Thanks Curious B,

the CEL (Check Engine Light?) if that is what CEL stands for is ON. it has been on since i had the issue with P/S and I have assmed it will be on until i finally replace the air control valve on the P/S pump.

Yea no idle issues but power issues for sure. and car seems loud like leak in exhaust system.

I just researched how to read the codes myself thanks to Lexls.com and am going to do this now.

I have not driven the car for 3 days since this happened and i joined the forum. However, I will take it for a 10 minute drive and check out the cats as you suggested.

More to come. And thanks for your time Curious B .

[greatwhiteshark]

OK i checked codes and here is the status.

25 - Air/Fuel ratio lean malfunction

28 - Main oxygen sensor signal (on right bank)

so those are my codes and the car is loud rough and has 30% of its normal power.

Again, I know i dumped a lot of ATF into the engine as a result of the failed air control valve but there is no ATF in the P/S system now after i realized that the ATF was going into the engine.

I know i need to replace the air control valve on the P/S pump.

If I replace the main oxygen sensor on the right bank I am assuming it makes sense to also do the left bank?

I am also wondering if this will correct the lean air-fuel issue?

I appreciate any input.

[curiousB]

The O2 sensor code might not be a problem code but an indicator of other things. I just battled a P0430 code for 70-80 days and in the end it was a leak in the Y-Pipe in the exhaust after the secondary O2 sensors. No parts required, welded up the leak.

If you are reluctant to put $money$ in the car then I wouldn't replace the ACV on the power steering pump. I'd just disconnect the rubber hose to the intake manifold and plug it with a golf tee. Then find a cap or something to plug up the nipple on the PS pump so leaky fluid doesn't get everywhere. The ACV function is a nice to have not a need to have. Top up fluid and you can shed the popeye arms.

Then I'd move on to the ignition. Perform the glowing CAT test I mentioned. If you have a dead ignition bank the car will run like $#@*& and one CAT will glow cherry red from unspent fuel. If you have one of those passive I/r thermal guns then you can compare the CAT body temps to each other ( http://www.harborfreight.com/non-contact-laser-thermometer-96451.html ).

Another test is to have car warm and idle and then disconnect one side bank coil. If that side is dead already disconnecting it will make no difference. Then try the other side (reconnect the first bank you unplugged first). If unplugging one bank kills the car but the other doesn't you know you have a coil problem. Replace the coil that didn't make a difference.

Since it is running so rough it must be a significant matter. The AFT could have plugged up the CAT but It would happen gradually over a long period of time. Your case seems to suggest a sudden change in performance. This is more like a failed ignition coil.

What happens when someone revs the engine quickly and you feel exhaust. Is there good flow coming out the back end pipes?

[VBdenny]

Block off the vacuum lines to the PS pump and at the manifold connections. I used golf tees and tiny hose clamps. Stopped the smoke. All that ATF probably doens't do much for your spark plugs. Fix the smoke, then dump into a couple bottles of fuel system cleaner and go out and run it on the Interstate for awhile. You might just get lucky and that will clean it up.

[VBdenny]

Oh yeah, check the wire pack in the trunk hinge as they ground out and cause weird performance and gauge light issues.

[greatwhiteshark]

Thanks for all the input.

Finally back in town and checked the cats.

After a 15 minute drive with max speed of 40 mph while dark outside, I looked under at the cats and both red hot.

Given the timing of all this i do think it was all of the ATF backing into the engine due to failed air control valve.

Now need to order 2 new cats, jack it up and replace them. Not sure if i am going to plug the air control valve on the PS pump or replace it at this point. I am thinking of trying to remove the O2 sensor per code 28 and cleaning it before replacing it with a new one.

Any thoughts on trying to clean the O2 sensor instead of replacing it?

Ill post what i do and the results after the new cats are on.

thanks to all of u for weighing in on this. Cant wait to get the new cats cause I miss my ls400.

[greatwhiteshark]

It has been a while but wanted to provide an update.

So here is what happened: The air control valve failed and the PS fluid (dex/merc) was sucked in to the engine. The PS fluid does not atomize(burn) well and consequently filled up the cats. the clogged cats restricted exhaust flow and overheated. The Ceramic honeycomb material was destroyed and some of it has likely found its way into the resonator.

I have replaced the engine coolant temp sensor, both upstream O2 sensors, and both cats.

Still ran rough and low power. Can drive it for more than a 10 minutes or cats start to heat up again. Mostly at the backside flange. I have driven it 7 miles since new cats and O2 sensors have been put on.

Next I need to replace the resonator. I have 2 options. 1.) cut the resonator off and replace it with a straight pipe (about $80-100 parts and labor) or 2.) remove the entire center pipe section, Part # 17410-50021

http://www.lexuspartsnow.com/parts/l...410-50021.html

(this is about $550 part and an hour of labor).

The bottom line is that the 5 quarts of PS fluid caused a world of damage to the exhaust system.

once I replace the resonator ill provide what i hope will be a final update for the group.

[SRK]

I've used ATF for years to clean the carbon out of older engines and most engines will take it quite quickly. They smoke and carry on, but do burn it and it causes no harm. When it comes to catalytic converters there is a small chance that they will function poorly, but if they did the post-cat O2 sensors would trip a code. Even if they do, a few full throttle blasts up the highway will heat the converters and they'll clean themselves. They are designed to do that.

So I would not spend money on the exhaust system - that won't fix the running problem the engine has now. That the cats still heat up means too much unburned fuel is finding it's way into them. That's what causes an overheated cat - fuel, not oil. So fix the engine management problem - ignition or fuel, that is causing the problem. And then blast up the highway for a while.

[curiousB]

ditto. The fact its running rough and no power and red hot cats leans me towards looking at ignition over fuel to start with. These cars have known problems with the ignition coils failing and leaving the car running on 4 cylinders. That gets a rough ride plus a ton of (unburnt) fuel dumped into the exhaust system to burn up. That is why the CATs are red hot. It will damage them if you let it go too long and then you're getting the checkbook out for another pair of CATs.

Could be fouled plugs and bad plug wires too. I would start by checking the coils, plugs and wires and see if you can't get the engine running better.

[greatwhiteshark]

First of all thank you all for your input. I have been diagnosing this in the best way I know how with all of your input.

OK here is where I am.

Removed the resonator and replaced with a section of straight pipe. welded both ends.

Resonator was clean and did not even look like it needed to be replaced.

Still ran sluggish and rough. lower end of drivers side cat started to heat up and turn red again. passenger side similar but just barely red/pink also on the lower end of that cat.

Ran diagnostics and no error codes. I am thinking I leave the exhaust alone now and focus on the engine. Not going to drive it again as i am afraid to going to ruin new cats. I will start with the spark plugs. seems to be running on 4 cylinders. Perhaps drivers side cylinders are not firing because of all the ATF that got dumped into the engine??? Aside from the spark plugs all I know to do is more research.

Again, thank you all for sharing your experience here as I really miss driving my LS400.

[SRK]

The ignition coils don't set a code when they fail. Lots of things don't set a code. As mentioned before, by others, one coil can fail and the other produce a relatively smooth running, but low power, engine. The two coils are staggered in the firing order, and each fires two plugs on each bank. It sounds very much like you have a faulty ignition coil, which is why I said don't do any exhaust work, and B said test the coils.

More than likely it is a simple, and cheap, fix at this point. Figure out which coil has failed and all will be well.

[curiousB]

For all the time you have spent cutting and welding I would just go buy an ignition coil for $50-70 and swap it in place for one side. If it doesn't get better swap it over the the other side and replace the first one you took out.

An easy test is to pull the high voltage wire off of one coil while the engine idling. If that coil is dead you won't notice any change in the engine (because its running on the other four cylinders). Then try the same test on the other side. If that bank is running the engine when you pull that coil it will die instantly.

Probability of an ignition problem being at the root of this >80%, probability of a Catalytic converter being the problem <2%. I know where I would spend my time.

[greatwhiteshark]

Update: New ignition coil still issues

I noticed that only the drivers side cat is getting red hot. (bottom 40% of the cat). passengers side is not glowing or even a bit red. So I changed the drivers side igintiion coil. Good link here on how to change this one

http://us.lexusownersclub.com/forums...howtopic=60609

The old one was cracked on the front face. Install of the new coil went smoothly except for one thing, I did break the locking tab on the main wire going into the center of it. perhaps this is my current issue?? perhpas not?

I still have a noticable loss of power(not as bad as it was before the new coil but still noticable) and hot cat on drivers side. Not sure what to do next. Could this new cat have been runied so quickly? I have driven it a total of 25 miles on 4 occasions since I replaced the cats and 12 miles since replaced the failed ignition coil. I can get he car going 60-70 MPH but noticably slow.

Could the cat be plugged and causing my low power issues?

Could the lack of a locking tab on the main wire connecting to the front of the new ignition coil be the culprit?

Any thougths? and thanks!

[curiousB]

This isn't a catalytic converter issue. It would take weeks to plug a catalytic converter not four 25 mile trips......

You clearly have an ignition problem. What happens to engine when you just unplug the driver side coil? No change? What about the cap and rotor? Is the inside of the cap dirty and and creating a short path to ground? Clean it out with some alcohol and lint free cotton rag.

[greatwhiteshark]

Went To look at drivers side plugs. Found completely shorted ignition coil wire. Was hanging together by sheathing only. separated about 4" back from distributer side connection. All wires are original 1993 sumtomo and looked fine except ignition coil wire. Looked only at 2 plugs on drivers side and they were not fouled gapped at .44 and seemed fine.

Ordered original Lexus ignition coil wire.

Note the wire reference number is the same for both sides of the engine but the drivers side is longer by about 2 incheds and needs to be if it is going on the drivers side.

Anyway, new wire on and ran absolutely awesome... For a short time. Say, 5 miles.

No doubt, that the drivers side ignition coil and ignition coil wire needed replaced. Caps and rotors are next in my mind. Any thoughts?

[landar]

Thoughts? Yes. Replace ALL of your ignition wires, not just a select one or two. If they are original, they have been "baking" in that engine compartment for the past 18 years. Retire all of them. Ditto for the caps and rotors.