question about unburned fuel

Two weeks ago, was troubleshooting a misfire. While swapping injectors, one of them got stuck, thereby dumping fuel in the combustion chamber (was getting tons of white smoke and raw fuel smell).

I left the car alone for two weeks. Installed a different injector, changed the spark plug (other one was completely wet) and tried starting the car.

Did not want to start . Tried several times and it finally started. Left it idling for 30 seconds and logged misfire counts at the same time. There was none, which was good. So I think the car is now OK, BUT I was still getting lots of white smoke, which I believe is probably the left over raw fuel in the exhaust and stuff. So I turned off the engine fearing that the neighbors would freak out.. And now my garage really stinks

Questions:

Does it take a while to evaporate all this unburned fuel?

Any damage to cats, o2 sensors or anything else? All in all, I would say the engine was idling with a stuck injector for a total of probably 90 seconds max.

Seems a little odd to smoke that long, however did you change the oil, that raw fuel went to the oil pan. Be a good idea to do a oil change and take it out and drive it hard, as long as its not miss firing as you stated.

I really doubt you damaged anything like cat, O2 that quick.

I think before I put the 'good' injector, I did get some good amount of raw fuel into the system, cause I even noticed fuel sipping out the arm of the wastegate on the turbo :/ (that was two weeks ago).

You're probably right that some fuel must have sipped into the oil pan. Dang it. I only have 600 miles on this oil..

Another update. Today, I decided to drive the car to work (16 miles mostly freeway). It was just fine. Monitored everything.

After work, car did not want to start. Had to give it some gas and then it finally started.

Idled like crap. AFR at idle was going all over the place, but pass 3k rpm it was OK (probably open vs close loop or something).

When I got home somewhat in limp mode, uppipe was glowing red!! My cat is probably clogged and dead too now. Thoughts?

Another update. Today, I decided to drive the car to work (16 miles mostly freeway). It was just fine. Monitored everything.

After work, car did not want to start. Had to give it some gas and then it finally started.

Idled like crap. AFR at idle was going all over the place, but pass 3k rpm it was OK (probably open vs close loop or something).

When I got home somewhat in limp mode, uppipe was glowing red!! My cat is probably clogged and dead too now. Thoughts?

Glowing UP = clogged cat. Why hasn't it been replaced?

White smoke = coolant

Black smoke = burning too much fuel

Blue & Gray smoke = oil burning

Glowing UP = clogged cat. Why hasn't it been replaced?

Was going to, literally next month.

White smoke = coolant

Black smoke = burning too much fuel

Blue & Gray smoke = oil burning

Not necessarily. White smoke can equal vapors from unburdened fuel.

I am going to take the up pipe off within the next couple of days. Can it come out without loosening the engine mounts?

Also, how likely is it for the other cats to be clogged?

Man, this 20mn injector swapping has turned into a nightmare now .

On my way to work, I watched my A/F correction and A/F learning and it was acting great +/- 5% in any condition (idle,cruise,acceleration). But it is when I left work that the A/F correction was going all over the place (+25% and then -25%). But once I was pushing the car past 3k rpm, A/F correction seemed fine, no knock nothing. But idle was bad, roughness misfire counts for each cylinder, etc...

My theory is: on my way to work, I 'cooked' the unburned fuel on the cat thereby slowly clogging it. And then when I tried to leave work, the cat was now clogged and the car was performing poorly.

Since the front o2 sensor is so close to the uppipe, I am afraid the heat killed it.

Sure, I can do that. I need to check the specs in the FSM on these O2 sensors (resistance, voltage range, etc...).

On another note, just checked price on a new one. Not cheap!

Another update. Today, I decided to drive the car to work (16 miles mostly freeway). It was just fine. Monitored everything.

After work, car did not want to start. Had to give it some gas and then it finally started.

Idled like crap. AFR at idle was going all over the place, but pass 3k rpm it was OK (probably open vs close loop or something).

When I got home somewhat in limp mode, uppipe was glowing red!! My cat is probably clogged and dead too now. Thoughts?

I think it's very unlikely that your cat became clogged after you shut off the car. An idling car creates very little exhaust pressure and you should be able to idle reasonably well even with a bad cat. I would suspect that a fueling issue likely presented itself once your car cooled down from it's "healthy" drive to work.

Furthermore, at initial start-up cars run on open loop which means the O2 sensors are ignored. This tells me the O2 sensor probably wasn't the issue that caused the car to start hard and idle like crap. You can monitor open/closed loop on an Accessport to see what it's doing and when.

If the injector was malfunctioning (as it seemed to be previously), then the wrong A/F ratio would have definitely contributed to the hard start and bad idle. A vacuum leak could affect this, too.

Glowing UP = clogged cat. Why hasn't it been replaced?

How are both the front Air Fuel sensors acting? Is it really running rich? If a cat was clogged you'd have performance issues, like lack of power-exhaust cannot get out. So if you don't I'm thinking its just running rich and you have another issue that causes the Cat to get hot. And putting the DP will not fix that...even if it needs to be done.

A cat in the UP would also glow from elevated EGT (exhaust gas temps). I believe you can get high EGTs from running rich due to injector malfunction, boost leaks, or bad O2 sensor in closed loop mode. Constantly running rich would definitely cause a high EGT.

On my way to work, I watched my A/F correction and A/F learning and it was acting great +/- 5% in any condition (idle,cruise,acceleration). But it is when I left work that the A/F correction was going all over the place (+25% and then -25%). But once I was pushing the car past 3k rpm, A/F correction seemed fine, no knock nothing. But idle was bad, roughness misfire counts for each cylinder, etc...

 

My theory is: on my way to work, I 'cooked' the unburned fuel on the cat thereby slowly clogging it. And then when I tried to leave work, the cat was now clogged and the car was performing poorly.

 

Since the front o2 sensor is so close to the uppipe, I am afraid the heat killed it.

It's possible that heat killed the UP O2 sensor as a side effect of some other condition causing high EGT. But as I mentioned above, I'm skeptical that the cat got clogged so severely and so quickly. And a clogged cat would tend to idle fine and then choke at higher RPM and higher load, which doesn't match your symptoms.

Now I am confused .

All I know is my A/F corrections were OK on my drive to work (16 miles of mostly freeway speed). Arrived at work, A/F trims just fine, let it idle a bit. Idled OK.

Car did not want to start when I try to leave work. I had to give it some gas and then it started. A/F correction kept going crazy +/- 25% at idle and below 2krpm. A/F correction stopped going crazy past 3k rpm, and car boosted fine, no knock, power normal.

The night before my drive to work, I put fresh oil, rechecked for vacuum/boost leaks. None to be found.

I would also add that when that injector got stuck open two weeks ago, the 'roughness misfire' count in that cylinder was going crazy. So it was obvious something was wrong.

After I put a known working injector (a different one), the count stayed at zero.

And when I left work, even though I had a hard time starting the car, once it started, misfire count stayed at zero, which would make me think the injector was working OK?

I use this tool: http://legacygt.com/forums/showthread.php/btssm-bluetooth-adapter-app-229709.html which can log almost anything that can be read from the ECU.

But I won't be starting the engine until I inspect and replace the uppipe with a catless, and check the o2 sensor condition. I will also inspect the turbo, and first cat in downpipe.

I think there was seriously a ton of unburned fuel man. It stunk so bad (two weeks ago). Fuel was even sipping out the arm of the wastegate, it was that bad. And all that from a freaking stuck injector and only a few times trying to crank and run the engine. What a mess...

Update...

Took uppipe off the car. Cat did not disintegrate, nor the EGT sensor thank goodness. I tried to take some pictures of the cat. Taking picture on the EGT side is easy but the other side, it is very hard due to the bend in the uppipe.

Anyway, does not really look clogged IMO.

Also noticed that cylinder 2 exhaust valve stem is much darker compared to the other 3 cylinders (whitish).

To get everyone up to speed on my situation, engine apparently had valve clearance issue 13000 miles ago on cylinder 4 (2012). Shop adjusted clearance for all valves on the driver side bank. And since then, I noticed roughness counts on cylinder 2 at idle when warm, (none when cold at idle). Never threw a CEL though, until three weeks ago.

Swapped, spark plugs, coil packs. no change. Then swapped injectors and got one of them stuck in the process... Now I am here. Next step is leak down test.

I'll post some pictures.

When I had my PS spark plug wires accidentally swapped around it did not smoke at all, but the exhaust from the DP back was ORANGE hot I assume from the CAT burning off that xtra fuel from #1 & #3. I managed to run and get the camera to take a pic before the glow completely went away:

http://i.imgur.com/iXaNN6l.jpg