is there a way i could test the injector without taking it out? any data logging i could do to tell me what's up with it?

 

Odds are all 4 injectors will log the same inj duty cycle in miliseconds since all 4 are controlled by one feedback 02 sensor, but you could look at all 4 of them in a log I suppose.

 

I will have to try to do that, thanks.

 

It would probably just be easier to swap injectors and see if the issue follows.

 

yeah, i was hoping to do some checking before taking it apart. when i go to the dealer i like to know what's wrong so i can tell them so they fix it the first time, and if i start taking stuff apart i don't want to mess with that warranty..

 

So good news all (maybe this will be informative for anyone else has the same symptoms as me and the dealer is stumped).

Well after a year of taking the car to the dealer (and switching dealers), apparently, the dealer ended up narrowing it down to "perhaps a sticky valve." So they ran some sort of heavy duty fuel system clean on it. Well they cleared the codes, and its been almost 2 months and still no code, and no weird "burbeling" on the odd startup.

A year of frustration for what turned out to be a dirty, sticky valve. And hey I thought I was using the best possible fuel for my car... Just goes to show you, you never TRULY know what your getting from the pump. (places I fueled at were Shell, Petro, and mohawk(husky))

 

well that's one of the issues with Direct Injection. We don't have fuel passing through the valves. Probably should seafoam every six months. But no one has done a write up so I haven't braved it yet.

 

So, What exactly is seafoam? I've seen it done but have no idea how you do it, or what it really does. haha.

 

It's a heavy cleaner you put in gas tank, oil and into a vacuum line. The car sucks it in, soaks it up and it dislodges engine build up.

But on our cars because fuel doesn't pass over the valves they tend to stick. So by running a little Seafoam through a vacuum line it will lube the valves.

That being said, I don't know exactly where to put it in an LNF.

 

There is a 3/16" vac line on the intake manifold to the left of the purge solenoid you can use. A piece of tubing will slurp it up at idle very quickly, use a restrictor like a small welding tip in the line to limit the vacuum leak.

The pic has been posted before.

 

I don't get what sea foam is either and why we are doing it. What's wrong with stuff like 44k or MOA? Sea Foam seems more difficult

 

Well, bad news. The light came on again.. However it was off for a solid two months. So the clean helped, but didnt fix. Now they are saying another compression test showed that cylinder 3(cause of the misfire) was "a little under spec" so they are supposedly taking the engine apart and putting new rings and gaskets in. seeing if that helps anything....

My grandpa, who was a diesel mechanic, thinks its probably a bad injector that only acts up on the odd occasion in the right conditions, and once it warms up the problem goes away.

But I dunno, this is such an annoying issue...

 

Update:

So I got it back, works fine.

Apparently they took the engine apart to get at the valves, turns out at least 1 of the valves on cylinder 3 were really slimy. So they cleaned it up, replaced valve seals, changed the oil, and put it back together.

Well see if this fixed it. haha.

 

shitty deal that it took so long

 

Bringing back an older thread,

I have this exact same issue. Dealer replaced the ignition coil and spark plug in cylinder 3- CEL still comes on now but car doesn't idle as rough. So I eventually found time to get it back to them and they told me they are going to try replacing the injector. If that doesn't fix it then they are going to did deeper into the engine. Did replacing the injector solve it for anybody?

 

I had random misfires under 60mph for months to where it wasn't comfortable to even drive and we couldn't figure out the problem. We replaced everything from fuel to electrical and exhaust/intake. Finally a light came on for abs and esc service. We replaced the wheel bearing and wa la it was fixed the second i drove it after that. We believe it had a bad wheel sensor that told the cu it was spinning causing the ecu to say hey traction control kick in which intentionally misfires the engine so you can regrip the road. Just a suggestion for the running rich at cruise code and/or service abs traction and esc codes. Even no codes at all except random misfires as it took forever for the wheel code to pop up.