bgd73 Posted September 7, 2006 Share Posted September 7, 2006 I have got a 56ohm resistor for a pc fan. will that work? I would like to know before a bad experiment Link to comment Share on other sites More sharing options...
Davalos Posted September 7, 2006 Author Share Posted September 7, 2006 This is why you can fool the ECU by swapping a resistor in place of the solenoid. But isn't the EGR supposed to open & close? Are you saying everything is hunky-dory, it's just a glitch that the computer is reading? If that's the case, I'll just live with the light... Link to comment Share on other sites More sharing options...
Uberoo Posted September 7, 2006 Share Posted September 7, 2006 so you just splice in a 68ohm resistor to connect the two wires? Link to comment Share on other sites More sharing options...
Cougar Posted September 7, 2006 Share Posted September 7, 2006 But isn't the EGR supposed to open & close? Are you saying everything is hunky-dory, it's just a glitch that the computer is reading? If that's the case, I'll just live with the light... If this was my car I would want to find the source of the trouble. Yes, the solenoid is supposed to open and close so just swapping in a resistor to take the place of the solenoid is not the real fix in my book, though this will make the light go out if the solenoid is really the trouble. You also don't want to leave the warning light on since the ECU may go into the limp mode and if another more serious problem occurs you won't know about it since the light is already on. By placing the proper resistor across the ECU pin for the solenoid and ground you can see if the problem clears. If it does then the problem is with either the solenoid or the wiring to it. If it doesn't go out then the problem is internal to the ECU. Link to comment Share on other sites More sharing options...
Cougar Posted September 7, 2006 Share Posted September 7, 2006 so you just splice in a 68ohm resistor to connect the two wires? If the connection to the solenoid is ok then yes, the resistor will work. Link to comment Share on other sites More sharing options...
bgd73 Posted September 7, 2006 Share Posted September 7, 2006 .. You also don't want to leave the warning light on since the ECU may go into the limp mode and if another more serious problem occurs you won't know about it since the light is already on. By placing the proper resistor across the ECU pin for the solenoid and ground you can see if the problem clears. If it does then the problem is with either the solenoid or the wiring to it. If it doesn't go out then the problem is internal to the ECU. limp mode? Link to comment Share on other sites More sharing options...
Cougar Posted September 8, 2006 Share Posted September 8, 2006 The limp mode is a mode the ECU uses when some non critical things go wrong with the sensors. It allows the driver to still drive but the engine isn't running at it's best. Things like fuel economy suffer but you can still get home at least and get the car to the shop for repairs. Link to comment Share on other sites More sharing options...
bgd73 Posted September 8, 2006 Share Posted September 8, 2006 is it a guess or does the solenoid errors allow ECU full speed ahead? My car runs good. I tried the resistor trick, and now the only other solenoid valve is triggering an error... to hell with both those gadgets Is the one non-egr related doing something potentially important? Link to comment Share on other sites More sharing options...
Cougar Posted September 8, 2006 Share Posted September 8, 2006 I would guess that errors on the valves wouldn't be a problem. If both valves are having trouble I would make sure they both have a good ground connection on one of their leads and if that is ok then check the circular connector near the battery. They both run through that. You may fix the trouble by just pulling it apart and reconnecting it. Link to comment Share on other sites More sharing options...
Virrdog Posted September 8, 2006 Share Posted September 8, 2006 Okay, replaced both solenoids, connected the white connectors under the hood to clear the code ... and wham! Check engine light on again ... Grrrr ... I did this the other week. Once I got the resistors in everything was fine for 10 miles or so then the CEL lights up again. I checked everything out and it all seemed the same. I started to worry then went ahead and reset the ECU... but I undid the negative battery terminal and then hit the brake to drain out any capacitors (the door chime was still going until I hit the pedal :-\ ). Once I did this, everything was great. CEL turned off and has not turned back on after hundreds of miles. So I would try resetting the ECU in this method. Link to comment Share on other sites More sharing options...
Davalos Posted September 8, 2006 Author Share Posted September 8, 2006 I actually replaced the alternator today, which meant the battery was out for a few hours ... Got it all back together & took it on a test drive, CEL was out for the 1st 5 minutes (just like yours), and then "Poo!" back on. Been on again ever since. I haven't checked to see if it's still code 34 ... Sounds like I should start shopping for the EGR? Dealer wants $127, if i remember. I'd rather drink toilet water. Link to comment Share on other sites More sharing options...
bgd73 Posted September 9, 2006 Share Posted September 9, 2006 I give up. I am putting black electrical tape over the light. code 34 or 35 back and forth. To heck with it. Link to comment Share on other sites More sharing options...
Davalos Posted September 9, 2006 Author Share Posted September 9, 2006 I'm gonna keep pluggin' away ... I'll let you know what I find. I am worried about mileage ... someone told me I could get 40 out of this thing ... and I'm barely getting 28. Link to comment Share on other sites More sharing options...
daeron Posted September 9, 2006 Share Posted September 9, 2006 none of you with the CEL that "comes back after a few minutes of driving" have your green test mode/timing connectors connected do you?? because the ecu uses the timing connectors to enter diagnostic mode.. you plug in, and rev engine above 2k for over forty seconds, the CEL comes on.. or maybe it flashes. maybe its a dumb question. but maybe im catching a mistake?? just a thought. Link to comment Share on other sites More sharing options...
Davalos Posted September 9, 2006 Author Share Posted September 9, 2006 Nope. I just do my connectors for a few seconds ... Link to comment Share on other sites More sharing options...
GeneralDisorder Posted September 9, 2006 Share Posted September 9, 2006 Again - replacing the EGR itself will do nothing. The code is telling you that the egr SOLENOID is bad. Trace the rubber vac hose back from the EGR to the little black thing with the electrical connnector on it - that's the solenoid. Any old solenoid will work - some have used ones from older toyota's, etc. Frankly, no EGR is needed, it will not help your mileage or anything else for that matter. Replace the solenoid with a resistor, clear you codes properly, and you will NEVER have this problem again. GD Link to comment Share on other sites More sharing options...
bgd73 Posted September 9, 2006 Share Posted September 9, 2006 ok, a few q's. This isn't going as simple as it sounds. The resistor stopped one code for the egr solenoid, now the other solenoid has an error. does it need two resistors the same to fulfill the trick? I would like the one going into evaporator to function. I am pretty sure it does , but the resistor tricked ecu into thinking it is bad. Is it really bad? I saw the plugins for egr and the other solenoid are different, could I hook up the egr one to the other? if so, I can grab any one thats easier off of another soob someplace, only if I don't need two resistors, meaning no solenoid valves at all. :-\ I can tell when the one dealing with vacuum on the evaporator has a prob. My fuel tank really does use it. For months at a time there is no sign of it, that is how I know that one valve is good, and wanted. Link to comment Share on other sites More sharing options...
Cougar Posted September 9, 2006 Share Posted September 9, 2006 If the second code is coming on because of the resistor you installed you may need to use a different value. What size resistor did you use? If you used a 10 ohm resistor that may be too low. Link to comment Share on other sites More sharing options...
bgd73 Posted September 10, 2006 Share Posted September 10, 2006 If the second code is coming on because of the resistor you installed you may need to use a different value. What size resistor did you use? If you used a 10 ohm resistor that may be too low. I used a 56 ohm- and it did get quite hot. I will scrounge around for two more solenoids. the egr won't ever work again, but I really want the other to function. So, I am scrapping the resistor idea, unless i kill both solenoids. thanks for help- and sorry for robbing a thread Link to comment Share on other sites More sharing options...
timmo Posted September 11, 2006 Share Posted September 11, 2006 It seems like i'm missing something simple here, but I cant actually find out anywhere which connectors should be hooked up in order to clear the ECU codes > can someone help me with this? please..... Link to comment Share on other sites More sharing options...
Cougar Posted September 16, 2006 Share Posted September 16, 2006 The connections that need to be tied to the resistor are the two leads that go to the solenoid. I really don't recommend this procedure but it does clear the error. Link to comment Share on other sites More sharing options...
Davalos Posted September 16, 2006 Author Share Posted September 16, 2006 Okay, so I need to be treated like a 10 year old here ... This procedure is the same as just putting a piece of electrical tape on this light when it comes to Code34: EGR Curcuit. Correct? When I clear the code, the light goes off - if I do it by the connectors, or by disconnecting the battery, the light stays off for the 12st 5 minutes or so. Then, something happens, and the light goes on. And it stays on permanently. Now, WHAT is happenning? I am assuming the EGR valve is openning (or closing?), as it probably should. And then something happens (and I assume it has to do with the EGR Solenoid). The Dealer tells me replacing the EGR doesn't stop the code. They also tell me it makes NO DIFFERENCE AT ALL on gas mileage, performance etc etc. When I tell them about the solenoid trick, they just kinda say "Well, I wouldn't do that, but that wouldn't make any difference either. I'm having a rough time getting my brain around the concept of something having no purpose. Is the EGR solenoid the Tonsils of a Subaru? Again, forgive me for being dense about this, but I just don't get it. I have SO much time into this, and I'm coming to the conclusion that I have done pretty much nothing ... AND nothing really needed to be done, and there is no benefit whatsoever by fixing this problem? Let me try it another way: if money were absolutely NO object, what would be the correct fix, and would the fix merely be 'shutting off the light'? rather than any beneficial result? ... Link to comment Share on other sites More sharing options...
azsubaru Posted September 16, 2006 Share Posted September 16, 2006 I used a 56 ohm- and it did get quite hot. I will scrounge around for two more solenoids. the egr won't ever work again, but I really want the other to function. So, I am scrapping the resistor idea, unless i kill both solenoids. thanks for help- and sorry for robbing a thread 56 ohms should work, and putting one in the EGR circuit doesn't have anything to do with the purge solenoid, although you can use the same trick for it. All you're doing is fooling the ECU into thinking the solenoid is there and working fine. Here are two possibilities: 1) Make sure you replaced the right one - it's easier to cut the wrong wires than you might think. 2) You're burning a little less than 3 watts of energy, so the resistor needs to be rated for at least 5 watts or it will burn out. I'd recommend a ceramic resistor. Link to comment Share on other sites More sharing options...
azsubaru Posted September 16, 2006 Share Posted September 16, 2006 This procedure is the same as just putting a piece of electrical tape on this light when it comes to Code34: EGR Curcuit. Correct?... Sort of - it fools the ECU into thinking the solenoid is ok. When I clear the code, the light goes off - if I do it by the connectors, or by disconnecting the battery, the light stays off for the 12st 5 minutes or so.Then, something happens, and the light goes on. And it stays on permanently.... You've reset the codes, and then after a few minutes, the ECU notices the problem is still there. You just haven't fixed it yet. The Dealer tells me replacing the EGR doesn't stop the code. They also tell me it makes NO DIFFERENCE AT ALL on gas mileage, performance etc etc. When I tell them about the solenoid trick, they just kinda say "Well, I wouldn't do that, but that wouldn't make any difference either.... Replacing the EGR SOLENOID will fix a code 34, unless there's a broken wire or corroded connector somewhere. And believe me, there are guys on this board that know a lot more than the dealer about these cars. I'm having a rough time getting my brain around the concept of something having no purpose. Is the EGR solenoid the Tonsils of a Subaru?... It's for emmissions control. You can search on this board for arguments about what it does or doesn't do. AND nothing really needed to be done, and there is no benefit whatsoever by fixing this problem?... If you fix it, the light will go out, and you may keep the atmosphere a lttle cleaner. That's about it. Let me try it another way: if money were absolutely NO object, what would be the correct fix, and would the fix merely be 'shutting off the light'? rather than any beneficial result? ... The "correct" procedure would be to replace the EGR solenoid. Link to comment Share on other sites More sharing options...
Cougar Posted September 16, 2006 Share Posted September 16, 2006 The reason the code is being generated by the ECU is because it sees a problem with current in the EGR solenoid circuit. The ECU needs to see the proper current flow in the circuit or it will send out a code saying there is a problem with the circuit. This is the reason you can fool the ECU using a resistor is because the resistor limits the current to the proper amount the ECU wants to see. It makes the ECU think it sees the solenoid coil resistance. As it was mentioned earlier replacing the solenoid valve may not fix the problem since the trouble may be with the wiring between the ECU and the solenoid. Solenoid coils are pretty reliable so I would think the trouble is really with the connection to it. The problem may also be internal to the ECU. To see if the solenoid coil is ok you can measure the resistance of the coil. If you read something between say 40 and 120 ohms, as a guess, then the coil is good and the problem would appear to be with the connection to the device. My info for a SPFI system shows that the EGR solenoid ties to the ECU on pin 4 with a blue/red wire. You should be able to remove the connector to the ECU while the car is off and measure the resistance of the solenoid between pin 4 of the connector and ground. If the circuit is ok you will see the resistance of the solenoid coil. If you don't, then there is a problem with the wiring or the coil. Link to comment Share on other sites More sharing options...
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