universaljustin Posted July 22, 2013 Share Posted July 22, 2013 hi, first time poster, i just traded a 98 mazda b2500 for 97 subaru outback, and im hoping it works out for me... ive had a 91 legacy L wagon that ive been very happy with for a loooong time.its a 5 spd with about 170K on it. i dont know much about it, i just got it a couple days ago. i thought it might have been just misfires at first, but the diag didnt throw fuel inj low voltage until i reconnected the diag a 2nd time after changing to oem wires and plugs. im assuming these codes can be thrown at anytime and is stored in the computer and can be retreived anytime after, as opposed to it just throwing the code when the problem is happening only... CEL is on steady, flashes intermittently. its throwing fuel injector low voltage codes, as well as misfire codes on all cylinders. has a loss of power, shakes pretty bad at idol, the shake smooths out at about 2500 but doesnt go away completely. still runs, no overheating problems, in fact it's really hard to get the temp gauge anywhere near the middle. although ive put a short amount of miles on it, i can tell its eating gas much faster than my 91 legacy. i want to say there is more of a noise coming from around the #4 cylinder, but i cant really tell, and i dont have a stethoscope.have replaced wires and plugs with OEM. tried cleaning injectors with some fuel additive, to no avail. speculated many options but i figured i would run it past everyone here.i took a video of my car starting up, running, idling, and did some close ups on the exhaust for sounds etc etc to help with diagnosis. any help is much appericiated, im on a very very tight budget and need to get this fixed as cheap as possible. video i took of the car: thanks! Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted July 22, 2013 Share Posted July 22, 2013 Welcome to the USMB! It sounds like one of the cylinders isn't firing properly. What I'd suggest doing is pulling off, one by one, the electrical connector for each injector and see if it changes how the engine runs. If you find one that doesn't make any change or makes less of a change, you can isolate your troubleshooting to that cylinder. You can also do this same test with the spark plug wires to check the ignition system. Quote Link to comment Share on other sites More sharing options...
universaljustin Posted July 22, 2013 Author Share Posted July 22, 2013 ok i pulled the fuel injectors and pulling #4 makes no change so it must have something to do with that cylinder. i took a multimeter to the injectors, when engine is off it reads 9.9V, and when on, its reading 11.8 or so... is that too low? its all the same on every injector. low voltage codes are being thrown, as well as misfires on ALL cylinders. are the #4 cylinder issue, multiple injector low voltage and misfires possibly related or separate problems?? i dont understand why that cylinder wouldnt work and the rest do if the problem impacts all cylinders and all the voltage readings are the same. the ignition system seems to be functioning, not sure if its running properly or not, but it seemed to work when i tested them. bad ground somewhere? i live in eureka, a coastal town, its always wet here and things rust faster here. someone on another board suggested to run a ground wire from the negative battery terminal to a bolt on the alternator with 8ga wire. Quote Link to comment Share on other sites More sharing options...
Cougar Posted July 22, 2013 Share Posted July 22, 2013 The voltage going to the injectors should be about the same as the battery voltage. If the battery voltage is around 13 volts and the injector voltage is at 11.8 volts this might indicate there is a power connection problem to the injectors. You could try running a temporary power jumper lead to the injectors to see if that helps. I also recommend you clean the engine grounds to see if that helps with the misfires though that might be happening because of the low injector voltage. There could be a valve problem with #4 cylinder. If spark to the plug is ok and the injector doesn't have a problem then check the compression of that cylinder and compare it to the others. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 23, 2013 Share Posted July 23, 2013 What exactly are the codes you're getting? The code number, P0xxx, not the definition. Ground problem is certainly possible, check the main engine ground by the starter, and the ECU ground on top of the intake manifold. I'd also suggest unplugging the 3 connectors on the passenger side of the bellhousing to look for corrosion. I forget which one has the wiring for the injectors, its possibly just loose from where someone had it unplugged previously and didnt plug it back in correctly. Quote Link to comment Share on other sites More sharing options...
universaljustin Posted July 23, 2013 Author Share Posted July 23, 2013 p0261,0264,0270,301-304 Quote Link to comment Share on other sites More sharing options...
ivans imports Posted July 23, 2013 Share Posted July 23, 2013 comp test that hole and alt voltage check Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted July 23, 2013 Share Posted July 23, 2013 X2 on alternator voltage check. If the entrire electrical system is under 12v then you need to address that first. Like cougar said, if system voltage is normal and injecorr voltage is low its probably a power supply issue to the injectors. The large 16 pin grey connector on the bellhousing has the power supply and ground (ECU) wires for the injector harness. Definitely pull that one apart and check for corrosion/ poor connection. Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted July 23, 2013 Share Posted July 23, 2013 I know you said you checked the voltage, but did you happen to check the resistance of the injectors to see how they compare to one another? Quote Link to comment Share on other sites More sharing options...
Cougar Posted July 23, 2013 Share Posted July 23, 2013 When I posted on this issue earlier I didn't really consider the charging system being the cause of this trouble Fairtax4me. Now, after thinking about this again I actually feel there is a better chance of that being the real cause of the trouble rather than a power connection problem to the injectors. I think you nailed it. Quote Link to comment Share on other sites More sharing options...
ivans imports Posted July 24, 2013 Share Posted July 24, 2013 Any time i see more than 3 codes means somthing bigger is going on Quote Link to comment Share on other sites More sharing options...
Cougar Posted July 24, 2013 Share Posted July 24, 2013 I could see how low charging voltage could cause all of the code issues the OP stated were happening. Quote Link to comment Share on other sites More sharing options...
ivans imports Posted July 25, 2013 Share Posted July 25, 2013 the sensers and ecu working voltage range is about 13-14.5 volts if it gets down below 12 starts to loose signals operations spark gets weak injector pulse gets weak ect takes alot of voltage to run all that stuff. Anyway alt voltage no less than 13.5 no more than 14.5 anything over 15 bad under 13 bad Quote Link to comment Share on other sites More sharing options...
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