ten2doyle102 Posted August 1, 2016 Share Posted August 1, 2016 Long read, the list of symptoms and what I have tried is below. Hi, my name is Matt and I have owned my 100% stock 2009 LGT for a couple of years now, however since the day I bought it I have been struggling with misfires…. I know I know… go figure. I am usually pretty stubborn about bring my car to someone else to work on it, but this is getting annoying. It started out throwing the usual p0301, p0302, etc. etc…. so I did what anyone would do and when down the list of the usual suspects. Started with new plugs (later found out that I got the incorrect gap, took them out recently and fixed that and it hasn’t shown a misfire code for a couple of weeks), coilpacks, injector cleaner etc all to no real effect on performance. I also replaced the MAF as well at some point in there. After a number of months, it started developing a hard starting situation where on occasion it would take about 3-6 seconds of cranking to finally start. Once it starts, it has never shut off and typically if I were to shut it off and then try to restart it, it starts normally. Additionally, once it fires I get a very strong smell from the exhaust of unburnt fuel which to me eliminates the possibility of a fuel pressure issue since fuel must be present, it’s just not igniting. On the suggestion of a fellow subie guy, I went through and reset the valve lash as well. Unfortunately this didn’t do much for the performance either and I wasn’t really convinced it was the culprit but he insisted it was the problem. I also performed a Leak-down test and a compression test both of which came out good. So now this is where starts getting weird. Lately, it has been throwing a P2096, rear o2 reading lean. However, I had another local subie enthusiast plug his laptop into the ecu and found that it has actually been pulling more than 20% of the fueling from the car when under full load which tells me it's running rich. Why would the ECU pull fuel when the rear o2 is reading lean? No knock detected either and the AFR’s stay right around 14:1 when cruising, but drop to around 11:1 when under full throttle. I don’t believe I have an exhaust leak as it runs quiet and I don’t hear anything obvious…. Also, when under full throttle, the power “surges” in and out as it goes up the RPM’s and at some points will even get “stuck” at an RPM for a bit before continuing on. It just doesn’t seem to make any power and feels really sluggish. However, there have been days where the car just suddenly takes off like someone turned on a light switch… Finally, it threw an overboost code a few weeks ago when I decided to take it around a local Auto-x course. Quick list of symptoms: Hard starts most mornings or after sitting for 10-15mins. Unburnt fuel smell from exhaust upon startup Power sometimes surges at full throttle meaning, not smooth power delivery. After a full throttle run, I can smell a rotten egg/rich smell when I let off. This is only with the windows down P2096 code will pop up after a while after clearing any codes ECU fuel trims show it pulling upwards of 20% fuel under full load. Quick list of things I have tried: New plugs New coil packs New injectors New MAF New front O2 sensor Added extra ground cables Did the big three power cable thing Redid the valve lash Compression test and Leakdown both good. If you have read this far, thank you. I appreciate it. I just want this thing to run right since I really do like the car a lot. I have also searched everywhere for any boost leaks and have found nothing. It seems like it is making full boost @ 13.5psi and vacuum sits around 21-22mmhg. I am thinking its something electrical messing with the ignition, but I am not sure. Any insight would be grateful! Also, please note that this car is stock, no mods. Link to comment Share on other sites More sharing options...
Max Capacity Posted August 1, 2016 Share Posted August 1, 2016 Where are you located ? http://www.tuningalliance.com/home.html Contact Brain or Mike at TA if you need help data logging and getting your issues figured out. They can also get you most any part you need, the right part the first time. Do you have a lap top and can you data log ? 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
FJuan Posted August 1, 2016 Share Posted August 1, 2016 Your system is running lean, which means the sensor is picking up more air than fuel. Since you replaced several parts, I'm thinking you have an exhaust leak pre-turbo, most common is the UP gaskets. My wife's balls are delicious. Link to comment Share on other sites More sharing options...
ten2doyle102 Posted August 1, 2016 Author Share Posted August 1, 2016 Hi, I'll give it a look, could that somehow cause my hard starting issues and the fuel trims to be pulled back? Also, I am located in WI. I am going to look at downloading romraider tonight. Link to comment Share on other sites More sharing options...
FJuan Posted August 1, 2016 Share Posted August 1, 2016 Yes, download RomRaider and do some data logs, that will help. My wife's balls are delicious. Link to comment Share on other sites More sharing options...
ten2doyle102 Posted August 2, 2016 Author Share Posted August 2, 2016 What would be a good start for logging? Link to comment Share on other sites More sharing options...
ten2doyle102 Posted August 2, 2016 Author Share Posted August 2, 2016 I downloaded Romraider, but found out that my cable that I used when I had my audi isn't working too well so I will need to find something to replace it. However, I do have a program on my phone called "torque" which allows me to see real time data from the ECU. Is it normal for the MAP sensor to read like it's under pressure at all times? it was showing 20-25psi when cruising and about 39 or soe when full throttle. Just trying to learn what is normal for this stuff. Thanks! Matt Link to comment Share on other sites More sharing options...
rhino6303 Posted August 8, 2016 Share Posted August 8, 2016 Check to see if your map sensor hoses are connected. It is bolted to your intake manifold above the turbo inlet. Link to comment Share on other sites More sharing options...
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