AdventureSubaru Posted March 22, 2012 Share Posted March 22, 2012 Replaced the engine in the 91 Legacy. 2.2 and everything matched up fine. Swapped over the fuel injectors, Idle Air control valve and a few other odds and ends from the lower mileage blown engine. (The donor engine is higher mileage and has sat for a few years.) Now, when I start the car, it usually just revs right up to redline and I have to turn it right off or risk damaging the engine. Sometimes it just sputters and I can keep it running by pushing the pedal and giving some gas, but it wont idle, it just dies. Start again and back to redline. I tried a few things. I have lots of spare parts. swapped MAF - no change Swapped TPS - no change Disconnected the Idle air control - no longer revs but still sputters. Maybe onto something? Removed and shot the Idle air control valve with carb cleaner. - no change As of now, my next thought it to try a different Idle Air Control Valve or swap the throttle body off the old motor perhaps? The idle Air Control was working as of december when the block self destructed. The current Throttle body has sat for the last 3 years. I seek advice! Link to comment Share on other sites More sharing options...
naru Posted March 22, 2012 Share Posted March 22, 2012 Swap IACs.That one sticks. Link to comment Share on other sites More sharing options...
bheinen74 Posted March 22, 2012 Share Posted March 22, 2012 second the iacv toss it in the garbage install a used one. once they stick, it is more than can be cleaned....they wear grooves into the insides and the grooves hang...... Link to comment Share on other sites More sharing options...
TheLoyale Posted March 22, 2012 Share Posted March 22, 2012 You can get a good one from Al's for about $30 or less, I replaced mine when I had the car. You will need one from an OBD-I motor instead of OBD-II as they are different (I learned the hard way) Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 22, 2012 Author Share Posted March 22, 2012 You can get a good one from Al's for about $30 or less, I replaced mine when I had the car. You will need one from an OBD-I motor instead of OBD-II as they are different (I learned the hard way) What's the cutoff on Legacies for OBD-I? 94 or 95? Link to comment Share on other sites More sharing options...
TheLoyale Posted March 22, 2012 Share Posted March 22, 2012 What's the cutoff on Legacies for OBD-I? 94 or 95? '94. 1995 got the OBD-II Duel Port EJ22 (First year) which is the motor to have really, OBD-II and Duel port! '96 would be single port. So you want '89-'94 for an IAC Also, yes the IACs look the same between OBD-I and II, and will bolt up. But the resistance is different as mine did not respond correctly. Link to comment Share on other sites More sharing options...
mattocs Posted March 22, 2012 Share Posted March 22, 2012 This might be a stupid question, but are the IAC the same on autos and manuals? Link to comment Share on other sites More sharing options...
987687 Posted March 22, 2012 Share Posted March 22, 2012 This might be a stupid question, but are the IAC the same on autos and manuals? Yep. Link to comment Share on other sites More sharing options...
ivans imports Posted March 22, 2012 Share Posted March 22, 2012 Check coolant level the idle moter is coolant temp related if low coolant the idle moter will not close properly sounds like air lock Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 25, 2012 Author Share Posted March 25, 2012 Check coolant level the idle moter is coolant temp related if low coolant the idle moter will not close properly sounds like air lock Coolant was low. I filled the radiator but the engine was dry to start. Added more and more coolant. Squeezing the upped rad hose keep producing bubbles. I disconnected the IAC and kept my foot on the gas to keep her running long enough to heat up and cycle coolant all the way through. Thermostat seems to be working properly. Now I'm no longer getting the redline revving when I start the car with the IAC connected but it's still running rough. I'm heading out for parts at pick n pull monday morning. I'll be looking for an IAC. The yard is over an hour away and parts are pretty cheap. Just in case it's not the IAC, any other parts I should look for as a plan B, plan C etc? Link to comment Share on other sites More sharing options...
CoupedUpSubie Posted March 25, 2012 Share Posted March 25, 2012 Did you clean the throttle body? That will effect idle. Make sure you buy throttle body cleaner and read the instructions. My car ran a lot better after cleaning the MAF and throttle body. Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 27, 2012 Author Share Posted March 27, 2012 I think that may be the next step. I replaced the IAC today and nothing has changed. Today I did notice that the gas pedal felt sticky the first time I pushed it. Am I on the right track in thinking it's time to pull the TB and give it a good cleaning? Link to comment Share on other sites More sharing options...
TheLoyale Posted March 27, 2012 Share Posted March 27, 2012 This is possible, as the throttle cable is directly connected to the Butterfly valve on the TB, so it that is sticking, that might be the hard/sticky feeling. I know mine had a pretty good carbon/gunk build up before I cleaned it. Removing the TB from the intake might be over kill, (Would need a new gasket) I just spray and wipe it out while its on the car, the extra carb cleaner isn't gonna hurt anything, nor will any type of dirt which comes off (As long as you catch most of it) This could also be a faulty TPS, but I haven't seen many fail, so its a crap shoot. As for cleaning the MAF, do NOT clean the sensor tong with carb cleaner or any other sort. Use a MAF or Electrical spray cleaner which is not corrosive. I used Carb cleaner on a MAF once and F*cked it up for good lol.. Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 27, 2012 Author Share Posted March 27, 2012 I have a pile of spare parts. The original motor with a hole in the block. A complete EJ18 and bolt ons from a 94 Impreza, and anything I feel like temporarily pirating from my Ej22 Impreza Outback. I already swapped the TPS just trying to eliminate some possibilities. No change. Ditto to the MAF. I connected the one off the Impreza. No change. Never had to mess with the TB. Does it have much in the way of moving parts? Looks simple to me. Then what? As i browse more and more posts I don't see many likely options. What causes freakishly high revs on startup? Could the injectors I swapped over be to blame? So much of the ignition/air/fuel systems would cause it to sputter and die, but what else is gonna make it rev? Link to comment Share on other sites More sharing options...
TheLoyale Posted March 27, 2012 Share Posted March 27, 2012 Possible Vac leak somewhere? Intake gaskets good? Getting down there with possibilities, after everything you have swapped. There really isn't much to the TB with moving parts, very simple. I don't know how different, even incorrect injectors, could cause a revving issue. It would just be over or under fueled. But it is good to look at all aspects. Link to comment Share on other sites More sharing options...
Fairtax4me Posted March 27, 2012 Share Posted March 27, 2012 I see you swapped the TPS, but did you calibrate it? The Ecu has to see 0.5v from the TPS when the throttle is closed or it will act stupid. Like revving the engine, or idling stupid, or bucking and stalling. What year engine did you install? Did you use the old wire harness or the one on the "new" engine? Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 27, 2012 Author Share Posted March 27, 2012 I see you swapped the TPS, but did you calibrate it? The Ecu has to see 0.5v from the TPS when the throttle is closed or it will act stupid. Like revving the engine, or idling stupid, or bucking and stalling. What year engine did you install? Did you use the old wire harness or the one on the "new" engine? I did not calibrate the TPS. Didn't know it was part of the process. How involved is that? The engine is also from a 91 Legacy and I used the "new" harness. Link to comment Share on other sites More sharing options...
heartless Posted March 27, 2012 Share Posted March 27, 2012 What year engine did you install? Did you use the old wire harness or the one on the "new" engine? The motor he got from me - same year as the car he put it into (1991) so wiring should not have been an issue - unless of course a critter did a little gnawing somewhere.... the motor came out of a known good runner (when we bought it - pre-cannibalization) car was purchased in northern Illinois and driven home to north central Wisconsin - only major problem that car had was really bad struts and body rot! he did have to swap over his fuel injectors (both were/are autos, so shouldn't be issues there either) and the front accessories as those parts were cannibalized for our daily drivers. Link to comment Share on other sites More sharing options...
NorthCoast Posted March 27, 2012 Share Posted March 27, 2012 After reading this thread I cleaned both my MAF and TB because I had nothing better to do. Now I have the same issue!! Idles at 1500 but comes down to 600 if I pull up on the pedal and occasionally bucks when driving. Looked up the TPS calibration. Here's what I found. http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/TPS_testing1.jpg http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/TPS_testing2.jpg http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/TPS_testing3.jpg Link to comment Share on other sites More sharing options...
95legwagon Posted March 27, 2012 Share Posted March 27, 2012 What's the cutoff on Legacies for OBD-I? 94 or 95? i got mine from a 93 or 94 and i own a 95..... obd1 to obd2 worked for me..... my car is definitly obd2 and the cutoff date is 94 i believe.... Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 27, 2012 Author Share Posted March 27, 2012 After reading this thread I cleaned both my MAF and TB because I had nothing better to do. Now I have the same issue!! Idles at 1500 but comes down to 600 if I pull up on the pedal and occasionally bucks when driving. Looked up the TPS calibration. Here's what I found. http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/TPS_testing1.jpg http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/TPS_testing2.jpg http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/TPS_testing3.jpg LOL. Mine is way worse though. It goes right up to redline without fail. Slows a little at 6000 RPM but it just keeps going up. The IACs in both were loose. I could wiggle that little valve thingy inside with my finger. Neither seemed locked up. Shot the TB full of carb cleaner. No change. I'm starting to run out of ideas. What would make this thing rev out of control? Link to comment Share on other sites More sharing options...
TheLoyale Posted March 28, 2012 Share Posted March 28, 2012 I am fresh out of ideas as well, but I would really like to know the answer too! This is mind boggling. Probably something real easily over looked too Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 28, 2012 Author Share Posted March 28, 2012 Out of desperation/boredom, swapped over another throttle body. Figured it couldn't hurt. No change whatsoever. :banghead::banghead::banghead: What next? I've never been quite this stumped. Link to comment Share on other sites More sharing options...
TheLoyale Posted March 28, 2012 Share Posted March 28, 2012 Out of desperation/boredom, swapped over another throttle body. Figured it couldn't hurt. No change whatsoever. :banghead::banghead::banghead: What next? I've never been quite this stumped. Possible ECU malfunction? Link to comment Share on other sites More sharing options...
Fairtax4me Posted March 28, 2012 Share Posted March 28, 2012 Beyond the TPS or a seriously bad IAC I'd say the ECU is about the only other answer. Link to comment Share on other sites More sharing options...
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