subarurx yo Posted February 1, 2012 Share Posted February 1, 2012 i have a 1987 rx with a ea82t and when its cold it will run fine but after 5-10 miles it will surge really bad and jolt the car and the only way for it to stop is to rev it up, pop the clutch and go, then it will die and start and run for only about 1 second and die. after about 45 minutes it starts and runs like crap. i tested the ecu and got code 21 which i think is cts but when warmed up the temp reads normal. fuel presure reads about 38psi at idle so far i cleaned out the maf with carb cleaner and replaced the TPS i have a top mount intercooler with a bov and 2.5in straightpipe and is boosting 9psi on the stock waste gate anyway please help! thanks Quote Link to comment Share on other sites More sharing options...
AKghandi Posted February 1, 2012 Share Posted February 1, 2012 87 gl-10 ea82t you have the exact same problem i do. does it backfire? and bog down?. revs like crap and barely drivable? is crazy how you have the exact same problem. you should look at my thread.. help oh subaru gurus in dire need of assistance. ive narrowed it down to the intake gasket but im still not sure thats the problem maybe we can help each other out mine started after i turned the boost up a lil bit which is why im leaning tward intake gasket Quote Link to comment Share on other sites More sharing options...
naru Posted February 1, 2012 Share Posted February 1, 2012 (edited) i have a 1987 rx with a ea82t and when its cold it will run fine but after 5-10 miles it will surge really bad and jolt the car and the only way for it to stop is to rev it up, pop the clutch and go, then it will die and start and run for only about 1 second and die. after about 45 minutes it starts and runs like crap. i tested the ecu and got code 21 which i think is cts but when warmed up the temp reads normal. fuel presure reads about 38psi at idle so far i cleaned out the maf with carb cleaner and replaced the TPS i have a top mount intercooler with a bov and 2.5in straightpipe and is boosting 9psi on the stock waste gate anyway please help! thanks Fuel pressure is too high at idle. Should be 36 psi above manifold pressure. Assuming 17 inches of vacuum at idle and since 1 inch of vacuum =.491 psi. Idle fuel pressure shoud be 36 -(.491 x 17)= 27.6 psi (or even lower for a higher vacuum) Check the regulator retun line for restriction and the reg vacuum line and the reg itself. Edited February 1, 2012 by naru Quote Link to comment Share on other sites More sharing options...
skishop69 Posted February 1, 2012 Share Posted February 1, 2012 You have an air leak between the MAF and the throttle body. Split tubing or disconnected line. Spray brake clean over anything intake related while it's running and when the idle changes, you've found the leak. Quote Link to comment Share on other sites More sharing options...
naru Posted February 1, 2012 Share Posted February 1, 2012 You have an air leak between the MAF and the throttle body. Split tubing or disconnected line. Spray brake clean over anything intake related while it's running and when the idle changes, you've found the leak. What about the fuel pressure??? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 1, 2012 Share Posted February 1, 2012 (edited) Fuel pressure is too high at idle.Should be 36 psi above manifold pressure. Assuming 17 inches of vacuum at idle and since 1 inch of vacuum =.491 psi. Idle fuel pressure shoud be 36 -(.491 x 17)= 27.6 psi (or even lower for a higher vacuum) Check the regulator retun line for restriction and the reg vacuum line and the reg itself. I do not beleive that is accurate. 36 psi above manifold *pressure* means the fuel pressure is 36 psi till you hit boost and then increases with each pound of boost. When they say 36 I think they mean at idle with normal manifold vacuum already compensated for. At least that's what I think the manual is trying to convey. As to the OP's problem - I beleive you have a bad CTS. The gauge does not use the ECU's CTS - it uses a seperate gauge sender. So you can't assume that because the gauge is working the ECU is getting the correct coolant temp reading. The connectors like to get dirty also. GD Edited February 1, 2012 by GeneralDisorder Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 1, 2012 Author Share Posted February 1, 2012 ya i did once turn the boost up and something with my 20 dollar ebay mbc wasnt set right and was accidentally hitting about 18psi and blew the hg but i got another motor and tore the old one down and no visible damage was done, also never blew the intake manifold gasket either but all of the same electrical components were used and the same intake manifold. any ways im changing the dizzy out as my cap had scratch marks on the tabs inside of it, along with the rotor was scratched up but it was on tight and the screw was in. i was thinking that i may have screwed the dizzy up by missing a shift and hitting 7.5k rpm:( the head gasket seems to hold though, i used the fel-pro perma torque and gave it 60ft/lbs of torque Quote Link to comment Share on other sites More sharing options...
naru Posted February 2, 2012 Share Posted February 2, 2012 (edited) I do not beleive that is accurate. 36 psi above manifold *pressure* means the fuel pressure is 36 psi till you hit boost and then increases with each pound of boost. When they say 36 I think they mean at idle with normal manifold vacuum already compensated for. At least that's what I think the manual is trying to convey. As to the OP's problem - I beleive you have a bad CTS. The gauge does not use the ECU's CTS - it uses a seperate gauge sender. So you can't assume that because the gauge is working the ECU is getting the correct coolant temp reading. The connectors like to get dirty also. GD No,that is not what the manual says at all.You should try reading it sometime. I quote. "By returning fuel so as to balance the above pressure difference and the spring force,the fuel pressure is kept at a CONSTANT level 250.1 KPa(2.55 kg/cm2,36.3 psi) against the intake manifold pressure." Basic physics.Basic autoshop. The injector needs to see a constant pressure differential between the nozzle and the fuel supply to meter fuel accurately. Varying vacuum levels are varying pressure levels and the fuel pressure needs to follow along. If fuel pressure was constant w/o boost, non-turbo MPFI cars wouldn`t need a vacuum line on the pressure regulator. Edited February 2, 2012 by naru Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 2, 2012 Author Share Posted February 2, 2012 ok so i replaced the distributor and it started up right away, then continued to do the same thing, but when i disconnect the dizzy and reconnect it it starts right up, then after a little it will cut out and die and the only way to get it started is to disconnect and reconnect the plug. this has got me totally confused:confused: Quote Link to comment Share on other sites More sharing options...
AKghandi Posted February 2, 2012 Share Posted February 2, 2012 i know the feeling man. mines doing the exact same thing.... did you use crc maf cleaner? because thats what i used right before this all started.. and i also have the 20 dollar ebay mbc. Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 2, 2012 Author Share Posted February 2, 2012 i know the feeling man. mines doing the exact same thing.... did you use crc maf cleaner? because thats what i used right before this all started.. and i also have the 20 dollar ebay mbc. i never used maf cleaner but i used carb and electronic cleaner but this was well before the issues occured Quote Link to comment Share on other sites More sharing options...
AKghandi Posted February 2, 2012 Share Posted February 2, 2012 hmm.. well if you get it figured out let me know, im goin crazy with this dam thing. Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 2, 2012 Author Share Posted February 2, 2012 i just checked ecu codes again and i got 14,21,22,23 and 24 :-\ oh and i was just curious if the cts is the thingy with one wire next to the thermostat, because i replaced it with parts i had layin arround Quote Link to comment Share on other sites More sharing options...
naru Posted February 2, 2012 Share Posted February 2, 2012 ok so i replaced the distributor and it started up right away, then continued to do the same thing, but when i disconnect the dizzy and reconnect it it starts right up, then after a little it will cut out and die and the only way to get it started is to disconnect and reconnect the plug. this has got me totally confused:confused: This pretty much has to be poor connections/wires. Quote Link to comment Share on other sites More sharing options...
naru Posted February 2, 2012 Share Posted February 2, 2012 i just checked ecu codes again and i got 14,21,22,23 and 24 :-\ oh and i was just curious if the cts is the thingy with one wire next to the thermostat, because i replaced it with parts i had layin arround No,ECU CTS has 2 wires. Clear the codes and see what comes back. Quote Link to comment Share on other sites More sharing options...
AKghandi Posted February 2, 2012 Share Posted February 2, 2012 the cts is right next to the turbo its a 19mm with a 2 prong connector sticking right out of the coolant passage Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 2, 2012 Author Share Posted February 2, 2012 i found the cts with 2 wires and it was unplugged! because the plastic on the connector was old and all chipped up and very corroded so i replaced the cts and and cleaned the plug the best i could, but i still get the ecu code. anyways, so how do i clear codes? do i just plug the green connector in with the ignition on? Quote Link to comment Share on other sites More sharing options...
AKghandi Posted February 2, 2012 Share Posted February 2, 2012 i usually just unhook the battery for a few minutes. also check the wires to the cts and the connector mine the wires were frayed and the plug in was corroded. as soon as it was fixed the CEL went away immediately also does it run better with the maf unhooked?. Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 2, 2012 Author Share Posted February 2, 2012 with the maf off it kinda backfires and stalls Quote Link to comment Share on other sites More sharing options...
AKghandi Posted February 2, 2012 Share Posted February 2, 2012 Hmmm. So that's not your problem. Mine does that with the Maf hooked up. Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 2, 2012 Author Share Posted February 2, 2012 im gonna take my engine wire harness and replace a lot of the connectors to see if it works Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 3, 2012 Author Share Posted February 3, 2012 also is this normal? go to link for quick vid http://www.youtube.com/watch?v=Icl6408vg6g Quote Link to comment Share on other sites More sharing options...
subarurx yo Posted February 3, 2012 Author Share Posted February 3, 2012 just bought Bosch platinum plugs and it ran better but was still cutting out, then i connected the little green test plug and it completely quit the cutting out except when i take off it doesnt like it if i lug it and i gotta push the gas a little more than i should before it responds. i heard that when the green connectors are connected that the timing wont advance, is that true? Quote Link to comment Share on other sites More sharing options...
Turbone Posted February 3, 2012 Share Posted February 3, 2012 That and the fuel pump cycles every 2sec. Quote Link to comment Share on other sites More sharing options...
AKghandi Posted February 3, 2012 Share Posted February 3, 2012 I think your Maf might be out of whack I think that's what's wrong with mine. Quote Link to comment Share on other sites More sharing options...
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