clyons Posted March 22, 2011 Share Posted March 22, 2011 Car is at stage 2 for reference. So I have a bit of a conundrum at the moment. Within the last week I've been having some issues with the legacy, all engine related, but I can't find the source so I'm looking for help. Symptoms - Original · Originally the car was hesitating and stuttering. · Lost all throttle control – CEL regarding TPS, reconnected TPS and all hesitation disappeared. Symptoms - Current · Lack of power above 3000, feels as if timing is pulled ~10 degrees throughout boost, though this is not constant as it works perfectly sometimes. · Throttle response is terrible below 3000, often hesitates, loses power, regains the power then falls. · Free revving is extremely slow below 3000, often feels as if the engine literally gets stuck then dramatically shoots to redline. I did hear a clunk several times when letting off of the gas, seemingly a wastegate issue. · I ran logs, everything seemed alright, and throttle position seemed linear, without drop off. I was getting a knock advance of -10 often. Weirdly, the car was showing .70-3.00 current boost but the max values and graph were reading correctly. If I had to guess, I would say it’s a boost issue, but I hear no signs of a bad turbo…squeal, grinding etc. Link to comment Share on other sites More sharing options...
I Donated thefultonhow Posted March 22, 2011 I Donated Share Posted March 22, 2011 I assume you reset the ECU? If you ran logs, can you run LV, save a log, reset through there, the post the log? Link to comment Share on other sites More sharing options...
clyons Posted March 23, 2011 Author Share Posted March 23, 2011 here is the learning view and a log, check out the knocking...sensor issue? don't mind the maf, I caused that.Problem_knock.csv Link to comment Share on other sites More sharing options...
compsurge Posted March 23, 2011 Share Posted March 23, 2011 My guess is your Dynamic/ Ignition Advance Multiplier is at 0 (hence no power). Actually, it is (from the LV screenshot). Sounds all too familiar (ask me how I know!) Check for: turbo to intercooler leakblown out intercooler tabsleaks from intercooler to throttle body hoseTurbo inlet hose for leaks (holes, tears, etc.)all vacuum lines and boost lines to make sure they are connected. You may also want to look under the intercooler for the famed blue T-fitting, as this has a tendency to blow out one of the hoses under stage 2 boost.dual mass flywheel may be broken causing clunking that is triggering knock sensor (this is a theory of mine)spark plug gap incorrect - should be around 0.029" Link to comment Share on other sites More sharing options...
clyons Posted March 23, 2011 Author Share Posted March 23, 2011 Log is up now, took a bit to get under the required file size. My guess is that something is causing false knock around 2000+ rpm, causing timing to be pulled there. After I reset the ecu it ran beautifully but as the log shows I'm still getting crazy knock at that throttle range. Interesting thought about the flywheel, though I changed that to the wrx lightened one. Link to comment Share on other sites More sharing options...
compsurge Posted March 23, 2011 Share Posted March 23, 2011 Hmm... how long ago was the flywheel changed? It is apparently not uncommon for that flywheel to cause chatter that is picked up by the knock sensor. Might be of some use to look at my quest for a similar issue plaguing my car here. If you are running the stock TMIC, I would suggest a close inspection of the tabs on the lower left side near the turbo. The slightest separation will cause lean conditions. Link to comment Share on other sites More sharing options...
compsurge Posted March 23, 2011 Share Posted March 23, 2011 Looking at your log, we seem to be having similar issues. All occur at low load, under less than 0.8-0.9g/rev engine load. Check the knock sensor trigger range. Subaru raised the starting value to 0.8g/rev in the 2008 WRX (same engine as the 05-06 LGT). What map are you using? It may just be engine noise. When you get a chance, can you also log the Ignition Advance Multiplier? Link to comment Share on other sites More sharing options...
clyons Posted March 23, 2011 Author Share Posted March 23, 2011 I logged the IAM, constant at 1. Tuning was done by infamous1 and I have to give it to him as the tune is great. The knock issue is a new development so I'm not sure what exactly changed. The tabs you speak of, they are beginning to pull, but only the two on the lower left hand side and I do not think its at a point to cause leakage, but I have noticed a slight increase in turbo noise...unsure if this is related or if I actually listened to the car being spring and having the windows down. Link to comment Share on other sites More sharing options...
compsurge Posted March 23, 2011 Share Posted March 23, 2011 Mine was like that when it blew. I wouldn't have ever noticed it if I wasn't looking for it. You can try using a vise grip to press it all back and see if it runs a little smoother. Link to comment Share on other sites More sharing options...
rock2534 Posted March 23, 2011 Share Posted March 23, 2011 Just curious, but what boost levels are you running? Just wondering at what point the stock tmic can start to give at. Link to comment Share on other sites More sharing options...
clyons Posted March 23, 2011 Author Share Posted March 23, 2011 I'm running 17.5psi at max. Link to comment Share on other sites More sharing options...
clyons Posted March 23, 2011 Author Share Posted March 23, 2011 I think the stock cooler will support 17psi, though not particularly efficiently, but anything higher will start to pull it apart. However, I don't think thats the cause of this knocking. Link to comment Share on other sites More sharing options...
compsurge Posted March 23, 2011 Share Posted March 23, 2011 Mine blew on stage 1 LOL. Link to comment Share on other sites More sharing options...
clyons Posted March 26, 2011 Author Share Posted March 26, 2011 Alright, I'm narrowing this down. Getting p2096 codes on the car, so we're running lean but I haven't determined if its a boost leak or o2 sensor. Ideas? I'll be logging boost pressure and 02 voltage. Link to comment Share on other sites More sharing options...
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