keithk831 Posted June 29, 2010 Author Share Posted June 29, 2010 That seems to indicate a lean setup, which leads me to suspect that an injector or O2 sensor is the problem. But swap around the coil packs first and see if the problem moves. It may be a temperature related problem. You can probably find a cheap multimeter at Autozone for $10 or $20... Sufficient for car use. Just don't mix up measuring amp and volt! Thanks for the input. If it was an o2 sensor problem though, wouldn't it be more of a widespread problem? Like more than just one cylinder all the time when cold? Link to comment Share on other sites More sharing options...
keithk831 Posted June 29, 2010 Author Share Posted June 29, 2010 Also, would buying some used yellow side-feed injectors be ok? I would think that would be more consistent than a brand new one. Link to comment Share on other sites More sharing options...
boymk123 Posted June 29, 2010 Share Posted June 29, 2010 Also, would buying some used yellow side-feed injectors be ok? I would think that would be more consistent than a brand new one. I would recommend to go with OEM... Link to comment Share on other sites More sharing options...
birkhoff Posted June 29, 2010 Share Posted June 29, 2010 I have a very similar problem. 2005 LGT at 150,000 miles. Cylinder 2 misfire for the last 6 months. Moved everything around and the P302 code goes away but the misfire is still there cold. Leakdown is fine; 5% to 7% across all cylinders so I don't think a valve or piston problem is behind it. I'll be very curious to find out what is behind my problem, or yours, whichever comes first! good luck. Link to comment Share on other sites More sharing options...
McDowell Performance Tunin Posted June 29, 2010 Share Posted June 29, 2010 Keith, you can log your battery voltage in RR. If that looks fine swap the injector with injector #1. if you're still misfiring, swap the coil pack with cylinder 1's coil pack. www.facebook.com/mcdowelltuning [sIGPIC][/sIGPIC] Click Here for Stage1, Stage2 and Stage3 Tuning and eTuning Info Link to comment Share on other sites More sharing options...
McDowell Performance Tunin Posted June 29, 2010 Share Posted June 29, 2010 I have a very similar problem. 2005 LGT at 150,000 miles. Cylinder 2 misfire for the last 6 months. Moved everything around and the P302 code goes away but the misfire is still there cold. Leakdown is fine; 5% to 7% across all cylinders so I don't think a valve or piston problem is behind it. I'll be very curious to find out what is behind my problem, or yours, whichever comes first! good luck. yours could be your OCV for the #2 and #4 cylinders. It will also cause the P0302 code. www.facebook.com/mcdowelltuning [sIGPIC][/sIGPIC] Click Here for Stage1, Stage2 and Stage3 Tuning and eTuning Info Link to comment Share on other sites More sharing options...
ehsnils Posted June 29, 2010 Share Posted June 29, 2010 Thanks for the input. If it was an o2 sensor problem though, wouldn't it be more of a widespread problem? Like more than just one cylinder all the time when cold? Not necessarily - it depends on how bad the sensor is. But I agree that it's a good idea to try to swap things around first and see if the problem moves. As for new injectors - if you haven't done any tune on the car you should stick to injectors with the same flow as the stock ones. Higher flow injectors means that they need shorter opening time at idle to get the correct amount of fuel injected - and the ECU isn't tuned for them either so it may be a chain of other events appearing too. Replacement injectors with the same flow is OK. A matched set is preferred since that means that you should get best possible result from them. Link to comment Share on other sites More sharing options...
Jens05LegacyGT Posted June 29, 2010 Share Posted June 29, 2010 I had the same issue, occasionally a rough idle. New plugs in, swapped coils, still same thing with P0302. Swapped 2 and 4 injectors and no rough idle, runs smoother than when I got it. Even when I first start it in the morning, smooth idle. Link to comment Share on other sites More sharing options...
birkhoff Posted June 29, 2010 Share Posted June 29, 2010 yours could be your OCV for the #2 and #4 cylinders. It will also cause the P0302 code. Been there done that. Had an P0021 when I got the car, so I replaced both OCV valves. Power seemed to drop significantly after that (timing dropped back?). The P0302 came shortly after. I did get rid of the code by swapping stuff around, but it might be just threshold as it still idles poorly. Next step is a full set of cleaned and calibrated injectors. Link to comment Share on other sites More sharing options...
keithk831 Posted July 5, 2010 Author Share Posted July 5, 2010 Ok, so I just tested my battery (I wanted to wait until it was fully cold). About 12.5 volts with the engine off, and around 14.6 with engine at startup (fully cold). Edit- And no weird fluctuations while testing (although I had to find a "good spot" to make contact). Link to comment Share on other sites More sharing options...
mineENGR Posted July 6, 2010 Share Posted July 6, 2010 I'm having the same problem, haven't investigated anything yet. Subscribed Link to comment Share on other sites More sharing options...
keithk831 Posted July 7, 2010 Author Share Posted July 7, 2010 Update- I just swapped coilpacks 4 and 2....misfire is still on cyl 2, so i'm assuming it's an injector problem. I'm going to read up on swapping injectors to see if I want to do it right now. Edit- Gonna go swap injectors right now. It looks pretty easy based on my Haynes manual. Link to comment Share on other sites More sharing options...
McDowell Performance Tunin Posted July 7, 2010 Share Posted July 7, 2010 it's easy, should take you 10 min. www.facebook.com/mcdowelltuning [sIGPIC][/sIGPIC] Click Here for Stage1, Stage2 and Stage3 Tuning and eTuning Info Link to comment Share on other sites More sharing options...
keithk831 Posted July 7, 2010 Author Share Posted July 7, 2010 Swapped injectors 1 and 2 (the two front ones). Misfire is now on cylinder 1, and it's misfiring way more (at least, the count is higher). So it looks like injector needs to be replaced. Now it's time to find a set. Should I go for yellows, or something else like pinks? Edit- Just looked around and it looks like pinks won't work on my car. So yellows it is! Called the guy on KSL and i'm going to pick them up this afternoon. Link to comment Share on other sites More sharing options...
keithk831 Posted July 7, 2010 Author Share Posted July 7, 2010 So I just tried idling my car to see if the misfire would get better after running for a minute. The car started sputtering and the exhaust smelled strongly like gas, so I shut it off. I think the injector has failed completely. Going to have to borrow my wife's car to drive up to SLC to pick them up in a couple hours. Found the problem, now I can't even drive my car. This sucks. Link to comment Share on other sites More sharing options...
McDowell Performance Tunin Posted July 7, 2010 Share Posted July 7, 2010 Yeah, 05-06 use side feed. Plus the pink's do not flow that much higher and are top feed. Not worth it. www.facebook.com/mcdowelltuning [sIGPIC][/sIGPIC] Click Here for Stage1, Stage2 and Stage3 Tuning and eTuning Info Link to comment Share on other sites More sharing options...
fuggers Posted July 7, 2010 Share Posted July 7, 2010 At least you were at home and still not questioning the problem. Solution in sight, hopefully this will fix it for you. Link to comment Share on other sites More sharing options...
jmorris6689 Posted July 7, 2010 Share Posted July 7, 2010 im having the same problem. cyl 2 misfire at idle Link to comment Share on other sites More sharing options...
keithk831 Posted July 7, 2010 Author Share Posted July 7, 2010 At least you were at home and still not questioning the problem. Solution in sight, hopefully this will fix it for you. Yeah really....and today is my day off. Hopefully I can get it all fixed by the end of the day. Link to comment Share on other sites More sharing options...
keithk831 Posted July 7, 2010 Author Share Posted July 7, 2010 im having the same problem. cyl 2 misfire at idle Well I may have some extra injectors for sale once I get this fixed. I'm buying three but I probably only need one. Once I get everything back together i'll keep an ear out for misfires for like a week. If there are none, i'll sell the remaining good ones. Link to comment Share on other sites More sharing options...
ehsnils Posted July 7, 2010 Share Posted July 7, 2010 You should make sure you have a matched set to avoid unnecessary strain on the cat. And unbalanced injectors can also cause burnt valves if it's bad enough. I had that on an old car - one cylinder was running too lean and the exhaust valve had a crack like a missing pie slice. Link to comment Share on other sites More sharing options...
keithk831 Posted July 7, 2010 Author Share Posted July 7, 2010 You should make sure you have a matched set to avoid unnecessary strain on the cat. And unbalanced injectors can also cause burnt valves if it's bad enough. I had that on an old car - one cylinder was running too lean and the exhaust valve had a crack like a missing pie slice. Isn't that something you could log to make sure that isn't happening? Link to comment Share on other sites More sharing options...
Beastarino Posted July 7, 2010 Share Posted July 7, 2010 Good luck with the fix Keith - Hope it works out for you. Link to comment Share on other sites More sharing options...
keithk831 Posted July 7, 2010 Author Share Posted July 7, 2010 Good luck with the fix Keith - Hope it works out for you. Thanks! Your luck worked! Ok, so I went up to SLC this afternoon (in my wife's car, which has no cruise control ) and picked up the three injectors. Replaced the injector on Cyl #1 (which was formerly on Cyl #2) and fired her up! At first it was a little rough and I could smell gas in my exhaust because it was fully cold. So I did an ECU reset using Learning View and started from there. It's running like a charm, with the misfires gone! I even took it for a drive and did a 3rd gear pull, and took a few LV screenshots during the process. Logan's map is perfect! I'll keep observing it for the next week and see how things develop. Now the only concern/issue I have is making sure, like ehsnils said, that i'm not running too rich/lean on any particular cylinder. Any suggestions on what I can log to do this? Note- the injectors I picked up are used, and from an STi. I'm thinking i'll run a bottle of injector cleaner to make sure everything is consistent. Link to comment Share on other sites More sharing options...
McDowell Performance Tunin Posted July 7, 2010 Share Posted July 7, 2010 So, now your injectors are a bit larger (about 565vs520) Was the pull from my map? If so, the numbers are pretty decent, for the weather. Check your email www.facebook.com/mcdowelltuning [sIGPIC][/sIGPIC] Click Here for Stage1, Stage2 and Stage3 Tuning and eTuning Info Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.