Misfire?

VICSVX · #1 05-31-2013, 11:18 PM

Srry if the question is floating around and I haven't found it. But need to know ASAP.

Today she started to sound funny through exhaust. Sounds like a wrx (which is cool) but means something is wrong. Also was gutless. So how do I pin point the problem? I'm figuring it's injector/s, wires, plugs, or coils. As a side note, she was smelling like something was burning and when I pipped the hood white smoke rolled out in a thin sheet. I started her up again to see what I can see causing the oke but no dice. It's is leaking oil so thinking oil is burning om exhaust.

Srry for any typos, I'm on my cell. Thanks guys

Conn SVX · #2 06-01-2013, 06:19 AM

Just throwing this out there. I had that problem. I had the car checked and they found that my spark plugs had come lose. Just a guess. I am sure it is not but check it anyway sounds like the same symptoms.

VICSVX · #3 06-01-2013, 06:55 AM

Ok ill give that a whirl tonight. You don't think any harm will come to the car driving it with the symptoms do you? My daily driver and only car...

BackWoodsBob · #4 06-01-2013, 06:57 AM

Having similar issues..... minus the smoke. I think one of life of my coils are grounding out. I'm going to test them tonight and if they're bad I'm going to replace them with those universals from summit racing.

icingdeath88 · #5 06-01-2013, 11:52 AM

I think coils or plugs are the most likely suspects here. One way to test which cylinder is misfiring is to unplug the injectors one by one. The one that doesn't make it sound different is the one that's misfiring.

VICSVX · #6 06-01-2013, 04:25 PM

ok i gave it a quick look around....have to wait till she cools off a bit before i start trouble shooting. it was 106 degrees today so its a lil warm outside lol

as for the smoke....its coming from the undercarriage bhind the precats....why would there be smoke from there? only thing i can think of is oil is getting blown back from driving....but it seems like a lot. rear main? i checked oil level and it is low and i just did an oil change few 100 miles ago.

VICSVX · #7 06-01-2013, 09:00 PM

so, after some tinkering and some looking...I don't think there is a misfire. I do believe that my precats are plugged thus giving me lack of power and different exhaust sound....also the white smoke is the precat cookin my undercarriage and melting the undercoating!! woah! anyone know if its legal in AZ to run with just a main cat?

Tapani · #8 06-01-2013, 09:45 PM

Both of them?

Do you have your check engine light on?

Grossly excessive fueling will make the cat "glow". I have witnessed this with my Saab 9000 - lost the ingnition coil/module pack (direct ignition casette), the car rolled to a stop - it was night in the dead of the winter. Man it scared me when orange light glowed from under the car, when it was pitch black otherwise.

I had a spare at home and it was on the edge of walking distance, so I bit the bullet and was back on the road within two hours.

The cat was fine after the incident.

If you continue to drive you will destroy the cats - the cores will melt - and risk setting the whole vehicle on fire.

Tapani

BackWoodsBob · #9 06-02-2013, 08:27 PM

Well, I do have a random misfire issue, anyone got a link or model number on those ignition coils?

I think EFI used the coils in their car too, gonna go dig up their thread.

Conn SVX · #10 06-03-2013, 06:09 AM

There are always some for sale in the for sale section... Did you try the test yet. ( unplug one at a time )

BackWoodsBob · #11 06-03-2013, 08:35 AM

working on that today, issue is is that it's incredibly random. It's either a coil going out, or my tps dieing but I doubt that it's the sensor.

Going to seal up my exhaust leaks today and unplug injectors.

VICSVX · #12 06-03-2013, 01:08 PM

i took the exhaust out and checked each cat for any rattle...none what so ever. i put it all back together and still the same problem.

sounds like a wrx, loss of power...didnt drive it too long as i dont want to see the cats warm up again. any ideas??

BackWoodsBob · #13 06-05-2013, 06:33 PM

apparently I have lost a cylinder on my swap. Pull the injector, no change, pulled the ignition, no change, swapped injectors, no change.

Seems I have horrid compression on one cylinder. . . can't wait to see what my new engine runs like after I freshen it up a bit :devil:

TomsSVX · #14 06-05-2013, 07:03 PM

Bob, have you checked for spark or fuel yet? I wouldn't go straight to compression loss without checking the basics first.

Vic, try disconnecting the fuel injectors one by one until you find one or more cylinders that do NOT change the idle or create a worse missfire. This will help you isolate which cylinder(s) is causing the issue. Is the check engine light on?

It is not very safe the drive the car this way. Excessive fuel in the exhaust system can cause a fire if the cats get hot enough, not to mention it will and more than likely already has done damage to the cats.

If it is a single cylinder my money is on a coil since it seems like there is fuel if its getting to the exhaust. If it is multiple cylinders there could be a bad timing sensor. So try to isolate where the issue is stemming from

Tom

VICSVX · #15 06-05-2013, 09:31 PM

thanks Tom, always a great help

i did exactly what you said without reading your post till now. i first checked all spark plugs thinking that i could get an idea of whats goin on but no dice. i then put them all back in and started the engine and pulled each injector plug till #4 had no change. i swapped coil with one from the spare motor i have and boom...runs fine