thorne Posted November 7, 2008 Report Share Posted November 7, 2008 Ok, I've been kinda frustrated on this one and am sure it's a mechanical issue at this point. I've only had a issue like this once before and it was way leaner then this though and it was a fuel filter. I'm running a similar map to the one I street and dyno tuned on my car which was dead on before @ 11.5 I mean on the nose. For the past month I've seen it drift to 12. Which is to lean . The IDC's are the same. The learning seems the same at first and then drifts by ~5% max. The map like i said as almost identical to the one i dyno tuned that came out @ 11.5 dead on. What pieces can cause this? Clogged injector ? Fuel Pump failure ? How do I even test this? vacum leak ? Bad plugs? I've just been banging my head over this. I hate mechanical issues. I can look at logs/maps and find issues quickly but this is just irking me to hell. this is my car. The car has 91k on it. Had it's plugs changed around 80 along with the timing belt. Quote Link to comment Share on other sites More sharing options...
Cordell Posted November 7, 2008 Report Share Posted November 7, 2008 O2s? I'm not very familiar with your car, but I would start checking fuel pressure at the rail, if good you know everything is good up until the injectors. Scanning the O2s for slow or sluggish movement would indicate that they are getting worn out. Just some thoughts. Quote Link to comment Share on other sites More sharing options...
thorne Posted November 7, 2008 Author Report Share Posted November 7, 2008 at wot stock o2 does not matter. But It could make the bad learns off of it. I will compare it to the wideband tonight if I've got time Quote Link to comment Share on other sites More sharing options...
Cordell Posted November 7, 2008 Report Share Posted November 7, 2008 Those cars use a MAF? Quote Link to comment Share on other sites More sharing options...
dragknee66 Posted November 7, 2008 Report Share Posted November 7, 2008 Boost leak test. Retune. Weather changing Quote Link to comment Share on other sites More sharing options...
Farkas Posted November 7, 2008 Report Share Posted November 7, 2008 My first thought would be a fuel pump or even dirty injectors, and even more unlikely, Fuel Pressure Regulator? I don't know common failing points of Subarus but I would look into those before anything else. Depending how easy it is to get to your injectors I would inspect those first, simple to clean and could be an easy fix. Fuel pump, I don't know of any specific way to test that it's flowing properly or showing signs of failure, but do you have a fuel pressure gauge you can use? Process of elimination I suppose.. Another thing that occured to me, what type of fuel do you run through the car? I'm curious to know when gas stations start doing their winter fuel mixes(If there is such a thing?).. you could be seeing that difference? Quote Link to comment Share on other sites More sharing options...
Farkas Posted November 7, 2008 Report Share Posted November 7, 2008 Those cars use a MAF? Good call.. MAF was going bad on my VW and it was doing some weird things. Quote Link to comment Share on other sites More sharing options...
Cordell Posted November 7, 2008 Report Share Posted November 7, 2008 My first thought would be a fuel pump or even dirty injectors, and even more unlikely, Fuel Pressure Regulator? I don't know common failing points of Subarus but I would look into those before anything else. Depending how easy it is to get to your injectors I would inspect those first, simple to clean and could be an easy fix. Fuel pump, I don't know of any specific way to test that it's flowing properly or showing signs of failure, but do you have a fuel pressure gauge you can use? Process of elimination I suppose.. Another thing that occured to me, what type of fuel do you run through the car? I'm curious to know when gas stations start doing their winter fuel mixes.. you could be seeing that difference? Check while the car is under load, would be easy on dyno but that is why fuel pressure testers are available electronically and/or long. (sorry Thorne I don't have a nice one like I was talking about.) Quote Link to comment Share on other sites More sharing options...
thorne Posted November 7, 2008 Author Report Share Posted November 7, 2008 I'm going over to IPS to use some of there resources saturday. My injectors are a BITCH. The issue has been happening since shortly after the last track day I was at. It was not winter blend then . Gas wise I've done bp 93 and sunnoco 94. The thing thats bugging me is when I've richened it up it's seemed like it was not responding. I might strap it to the rollers this weekend. As for the MAF. That is a option but the G/s it's reading is almost exactly the same as it was on earlier logs with in a few grams. The boost is holding fine. I'm going to back it off because of me worring but on the tests it held 22lbs with out a issue. I just spoke to mike I'm going to test the fuel rail / clean the maf / and run a boost leak test. Man the more I think about it the maf does sound like a very possible culporite. Quote Link to comment Share on other sites More sharing options...
Cordell Posted November 7, 2008 Report Share Posted November 7, 2008 Thorne if you go to IPS let me know, I'd like to check it and your car out. Quote Link to comment Share on other sites More sharing options...
Farkas Posted November 7, 2008 Report Share Posted November 7, 2008 I'm going over to IPS to use some of there resources saturday. My injectors are a BITCH. The issue has been happening since shortly after the last track day I was at. It was not winter blend then . Gas wise I've done bp 93 and sunnoco 94. The thing thats bugging me is when I've richened it up it's seemed like it was not responding. I might strap it to the rollers this weekend. As for the MAF. That is a option but the G/s it's reading is almost exactly the same as it was on earlier logs with in a few grams. The boost is holding fine. I'm going to back it off because of me worring but on the tests it held 22lbs with out a issue. I just spoke to mike I'm going to test the fuel rail / clean the maf / and run a boost leak test. Man the more I think about it the maf does sound like a very possible culporite. My MAF caused my car to load up on fuel in half throttle conditions and run lean up top.. Unfortunately the MAF cleaner didn't help my problem either. Will your car run without the MAF? I simply had to un-plug mine(of course I had a CEL) and let the ECU run off it's learned tune and that pointed my problem directly to the MAF. If you can get away with that, give it a shot. If you have someone local, try swapping with a known good unit. EDIT* I've heard of people having problems with air filters being really dirty and running into problems like this. Have you cleaned or recharged yours lately? before I found a faulty MAF, I found mine was filthy when I was troubleshooting my own problems . Quote Link to comment Share on other sites More sharing options...
dragknee66 Posted November 7, 2008 Report Share Posted November 7, 2008 Before taking crazy steps like that I would just pressurize the whole system and check for leaks. Quote Link to comment Share on other sites More sharing options...
SpaceGhost Posted November 7, 2008 Report Share Posted November 7, 2008 Just let it go boom. Then put in the new engine you really want.... Quote Link to comment Share on other sites More sharing options...
thorne Posted November 7, 2008 Author Report Share Posted November 7, 2008 Just let it go boom. Then put in the new engine you really want.... If had the money I would yank this motor right now and have me eather a 2.3 stroker or a 2.5 or maybe 2.7 muahahha. nd2 I'll be upthere pm me your number I'll let you know what time. This has shown me that the safe modes in the roms really do work. So saturday. Pressure test #1 Fuel pressure test #2 Clean maf for good messure #3 I might pull a plug on Cyl #3 or #2 since I did show a misfire code. The problem with the misfire codes is I have a lightened flywheel so people report tossing false ones all the time. Thanks for the input guys. Again Praise Fuji Heavy Industries for making a very adaptive ecu. Quote Link to comment Share on other sites More sharing options...
Guest Removed Posted November 7, 2008 Report Share Posted November 7, 2008 weather change...cooler air=___________! or pump is getting weak... your over thinking shit tubby Quote Link to comment Share on other sites More sharing options...
thorne Posted November 7, 2008 Author Report Share Posted November 7, 2008 it was happening before the weather got colder. I was looking at my AFR and it's not matching between stock and wb its off by more then it was before at idle. I'm doing tests tommorow to get a better idea. Quote Link to comment Share on other sites More sharing options...
AJ Posted November 7, 2008 Report Share Posted November 7, 2008 you should start with the easy stuff first. air filter and clean the MAF. a dirty MAF can read dead on on the scan tool and still be the problem, fixed many cars with just cleaning it off and reinstalleing it. Quote Link to comment Share on other sites More sharing options...
thorne Posted November 8, 2008 Author Report Share Posted November 8, 2008 I'll let you guys know how it goes tommorow Quote Link to comment Share on other sites More sharing options...
1qwk767 Posted November 8, 2008 Report Share Posted November 8, 2008 if you need some help thorne you know how to get ahold of me buddy Quote Link to comment Share on other sites More sharing options...
skold Posted November 8, 2008 Report Share Posted November 8, 2008 clean your mass air flow sensor, those cars uses the same maf as toyota's when you take it out look at it there is a intake temp bulb and then when you look those it there are 2 wires, those read the amount of air flow,, i bet they are dirty, go to like napa and get crc maf cleaner spray it on the bulb and then down on those 2 wires, and blow gun it clean. Quote Link to comment Share on other sites More sharing options...
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