Quick question regarding injector swap and smoking

I upgraded injectors this past week which helped my idle and misfire issue greatly, however now if i run it for a minute or two at idle im getting smoke from the back of the motor.


I'm guessing this is just gas or oil burning off that may have leaked when I removed the fuel rail and fell onto the exhaust. Figured id ask before letting it idle any longer and possibly causing more of an issue :dunce:

What color is the smoke? could be a leaking injector, put a mechanical fuel pressure gauge on it, prime the motor, then let it leakdown, if youve got a sticking injector, pressure shouldnt last very long at all...

Gasoline evaporates quickly. Even if you spilled a bunch you shouldn't see smoke after the engine warms up.

No, don't smoke while swapping injectors! ;-) I couldn't resist, the way you titled the thread, that was the first thing that came to mind. lol

Smoke after idling for a minute or two is often valve stem seals. The high vacuum of idle will suck oil past weak seals in the valves and its builds up in the motor. If it all blows out after revving the motor or driving away.

People say burning oil is BLUE smoke, its really light gray smoke with a tinge of blue to it.

I think he is saying its from the back of the engine, not the exhaust.

Ahhh, in my rush to make a joke, I didn't read it well.

Valve cover gaskets tend to fail, oil will leak out if it does. That could cause some smoke if it burns, might have been doing for a while, you only noticed when you swapped injectors.

When I used a fel pro gasket, it didn't fit well, and leaked soon after, I got a different brand it fit and sealed much better.

I usually douche the engine down with Simply Green every once in a while, scrub areas with built up grime with a brush, and thoroughly wash it out. Of course there is always a risk the water gets in somewhere where it shouldn't, but when I experience it, it usually dry's out after a day.

At the very least, consider checking the bolt tightness of the VC bolts.

sorry for the delayed response, borrowed a set of injectors off a friend that are recently rebuilt and still smoking. Strange all this is happening after only changing the injectors. Its grey/white smoke, i don't notice any leak in the coolant and its hard to describe the smell.

After getting a better look it looks to be coming from around the cat area but once again this didnt happen prior to changing the injectors. so strange

Johnnie Walker said:

At the very least, consider checking the bolt tightness of the VC bolts.

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Checked and all tight. cleaned and washed everything.

It starts smoking after about 20-30 seconds not even warm.

Maybe its an o2? god this is annoying, I wish it would just throw a code or something.

I'll take a video in the morning maybe that will help

Edit: Just realized my dumbass didnt reset the ecu after the new injectors, but i dont think that would give me this issue correct me if im wrong... id love to be wrong right now.

Did you drive it? I would maybe take it for a drive and give a chance for whatever it is to burn off. I would make sure its not gas leaking first though of course. Who knows what has spilled or dripped down while you were working on it.