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White smoke and fuel smell from exhaust

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Old 06-12-2012, 08:43 PM
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White smoke and fuel smell from exhaust

Hello gents,

So I'm seeing a little white smoke from exhaust. A friend said it smells like fuel. I only really see when the car is warmed up. I recently had to reset the computer and an in the process of trying to go through the cycles so that I can hopefully grab some codes.
We live graphed some of the o2 sensors and all the graphs were pretty sparatic and inconsistent. However systems still aren't ready to be able to throw a code. Really a pain in the butt. Thinking that either not fully functioning sensors are causing the car to run rich/lean or maybe my cats may possibly be clogged? Would any of those cause smoke though?
Also on the highway my friend says that he smells a failing cat but also coolant. The coolant I'm assuming would be from all that spilled in the bay when trying to burp the system after replacing the waterpump. Also a huge pita but it was bubbling over like crazy for a long time and my coolant level isn't changing so don't think it's related.
I've been searching like crazy and the only other thing I saw with similar symptoms ended up being an injector that was not firing and the smoke was caused by unusual condensation from it not firing and it was a shirt thread with no other available info. I had the engine replaced with one with 6700 miles not too long ago and the injectors I doubt we're checked during install also could one be clogged from it sitting? It came out of an 04 so it had to been sitting for a while.
Can anybody verrify any of these possibilities while I'm still trying to get the monitoring systems up and ready?

Thanks in advance!
 
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Old 06-12-2012, 10:34 PM
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Originally Posted by blackout2277
Hello gents,

So I'm seeing a little white smoke from exhaust. A friend said it smells like fuel. I only really see when the car is warmed up. I recently had to reset the computer and an in the process of trying to go through the cycles so that I can hopefully grab some codes.
We live graphed some of the o2 sensors and all the graphs were pretty sparatic and inconsistent. However systems still aren't ready to be able to throw a code. Really a pain in the butt. Thinking that either not fully functioning sensors are causing the car to run rich/lean or maybe my cats may possibly be clogged? Would any of those cause smoke though?
Also on the highway my friend says that he smells a failing cat but also coolant. The coolant I'm assuming would be from all that spilled in the bay when trying to burp the system after replacing the waterpump. Also a huge pita but it was bubbling over like crazy for a long time and my coolant level isn't changing so don't think it's related.
I've been searching like crazy and the only other thing I saw with similar symptoms ended up being an injector that was not firing and the smoke was caused by unusual condensation from it not firing and it was a shirt thread with no other available info. I had the engine replaced with one with 6700 miles not too long ago and the injectors I doubt we're checked during install also could one be clogged from it sitting? It came out of an 04 so it had to been sitting for a while.
Can anybody verrify any of these possibilities while I'm still trying to get the monitoring systems up and ready?

Thanks in advance!
I always thought white smell with coolant smell = blown head gasket. But you are saying your coolant level hasn't changed. Try looking at your oil and see if it looks 'muddy'

It might be clogged injectors. No way of telling besides taking them out and cleaning. Tried seafoam?
 
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Old 06-12-2012, 10:45 PM
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I just had the headgasket replaced because I had rapid coolant loss plus the smoke but afterwards I come to realize that what I thought was coolant burning from the exhaust was whatever I have now and the loss of coolant was from my waterpump o rings being shot. I haven't tried seafoam yet because I don't want to fill my neighborhood with smoke but I might try that at night and see what happens
 
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Old 06-13-2012, 11:54 AM
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Originally Posted by blackout2277
I just had the headgasket replaced because I had rapid coolant loss plus the smoke but afterwards I come to realize that what I thought was coolant burning from the exhaust was whatever I have now and the loss of coolant was from my waterpump o rings being shot. I haven't tried seafoam yet because I don't want to fill my neighborhood with smoke but I might try that at night and see what happens
If you just had the gasket replaced then it might just be the residue burning off. When I had my engine swap done, the mechanic put in new gaskets (don't know which ones) and he said the smoke will persist for a few days. And he was right, it did disappear after driving for a couple of weeks.

Seafoam smoke only lasts for a few miles. Just take it to an empty lot and run your car for a few mins. Just make sure you follow the instructions though and don't put in more than you need to.
 
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Old 06-13-2012, 03:09 PM
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Don't think it's residue burning off because it was smoking the same exact way before the headgaskets got done
 
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Old 06-13-2012, 03:15 PM
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Do you have cats?

If you had coolant in the exhaust before, it will be a while before it finally burns out.

How far is your normal commute/driving? what's the ambient temp?
 
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Old 06-13-2012, 03:36 PM
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Stock cats. I don't think I had coolant in the exhaust because the headgaskets I thought were bad I don't think were because the problem never changed and the only coolant loss was due to water pump. A friend told me that it smells like fuel coming from exhaust.
I don't really commute with the car as its been sitting in my driveway until I recently got all the air bubbles out after the water pump.
 
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Old 06-13-2012, 03:44 PM
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Can it be a faulty injector that is spewing more gas than the engine can burn, hence excess gas coming out of the exhaust?

I am assuming no codes for misfire? (Even though you can have minor levels of misfire without triggering the code)

I would definitely suggest some fuel injector cleaner. I am also assuming you put in new spark plugs when you changed engines?
 
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Old 06-13-2012, 03:49 PM
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No codes cause had to reset computer and monitoring systems aren't ready yet. The spark plugs I honestly don't know. I pulled a few and they don't look hot so going to replace this weekend.
 
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Old 06-13-2012, 04:13 PM
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Originally Posted by blackout2277
No codes cause had to reset computer and monitoring systems aren't ready yet. The spark plugs I honestly don't know. I pulled a few and they don't look hot so going to replace this weekend.
Yea they might not be firing as efficiently since they were sitting around for so long. Look at the tips. Do they look fine? Also check the gaps
 
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Old 06-13-2012, 05:44 PM
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The 3 on the driver side all pretty much look like this..
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Old 06-13-2012, 08:26 PM
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Any idea how old these are? Did you swap them from your old engine or were these in the engine you bought that was sitting around for a while?

There is carbon build up but it doesn't seem that out of whack. Regardless, worth replacing IMO

I would change these first, then clean fuel injectors using seafoam and then if problem still persists, I would get the individual fuel injectors checked out.
 
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Old 06-13-2012, 08:43 PM
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Looks a tad hot, but nothing to worry about, little sooty.

If it sits around, it's full of condensation, it needs a long long drive and then give it a blast near the end, see what happens.

Also, any vid of the gas from the tailpipes?
 
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Old 06-13-2012, 08:49 PM
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I'll see if I can get a vid of it in the next day or so. I'm going to replace the plugs and try the seafoam this weekend hopefully. And I'm pretty sure these are the plugs that were in the motor and sitting.

If none of the above work any tips on checking the injectors? Luckily I took the ones off the old engine before I sold it so I have a full extra set in the garage
 
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Old 06-13-2012, 08:50 PM
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Also let's not mention how my throw out bearing is making crazy noise and it was replaced when I put the motor in in December. Fml lol
 
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