simbey1982 Posted June 21, 2006 Share Posted June 21, 2006 Hello all, Just so you are familiar, ive been doing a SOHC 2.5 swap into my 97 impreza L Sounds cool right....yeah that is if you dont get the wrong wiring harness and find out after youve spliced it in etc etc. Needless to say ive been fighting this for 8 months now. My current issue i ran into was that i was getting very odd spark or no spark on the coil. Tested absolutely everything and came to the conclusion that the timing had to be off or the sensor was dead. Got a new timing belt and put the bad boy on. Now the engine turns over find but doesnt fire (there used to be a cough ever 3 or 4 cranks) I am going to try swapping sensors to see if that works. but im concerned that if it made a diffrence to do the timing that i have a bent valve or 16. My buddy mentioned a leakdown test of some sort. How would i be able to tell i have a bent valve without taking the whole blasted thing out and taking the heads off? Thanks for any info Cory:horse:<- this is the best emoticon ever Quote Link to comment Share on other sites More sharing options...
nipper Posted June 21, 2006 Share Posted June 21, 2006 Hello all, Just so you are familiar, ive been doing a SOHC 2.5 swap into my 97 impreza L Sounds cool right....yeah that is if you dont get the wrong wiring harness and find out after youve spliced it in etc etc. Needless to say ive been fighting this for 8 months now. My current issue i ran into was that i was getting very odd spark or no spark on the coil. Tested absolutely everything and came to the conclusion that the timing had to be off or the sensor was dead. Got a new timing belt and put the bad boy on. Now the engine turns over find but doesnt fire (there used to be a cough ever 3 or 4 cranks) I am going to try swapping sensors to see if that works. but im concerned that if it made a diffrence to do the timing that i have a bent valve or 16. My buddy mentioned a leakdown test of some sort. How would i be able to tell i have a bent valve without taking the whole blasted thing out and taking the heads off? Thanks for any info Cory:horse:<- this is the best emoticon ever well one way is to hold your hand over the intake, you should only feel air being drawn into the manifold, not pushed out. Also you should still get some sort of combustion even with 2 dead cylinders. Lets check the basics: Do you have fuel Are the injectors getting an electrical signal Check the cam and crank sensors for a heart beat. Use an analog meter and crank the motor, i forget if its an ac or dc signal, it will be very low, but the needle should jump. Check that the ignitor is sending out a signal (see the haynes manual) Was this engine running before the transplant Exactly what did you have to splice in and where. nipper Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 21, 2006 Author Share Posted June 21, 2006 well one way is to hold your hand over the intake, you should only feel air being drawn into the manifold, not pushed out. Ill try that when i get home Lets check the basics: Do you have fuel Yes, the fuel pump charges and the spark plugs are wet with fuel after cranking...also the fuel smell after cranking Are the injectors getting an electrical signal Used a multimeter and the injectors are indeed pulsing Check the cam and crank sensors for a heart beat. Use an analog meter and crank the motor, i forget if its an ac or dc signal, it will be very low, but the needle should jump. My next move is to check the sensors, i also have some sensors i can swap in for test purposes Check that the ignitor is sending out a signal (see the haynes manual) The SOHC has the ignitor and Coil all in one unit. All signals going in seem to be fine. Also i switched it with another car, the other car started mine still didnt. Was this engine running before the transplant Yessir Exactly what did you have to splice in and where. Had to splice in ECU Power, Ground, AC junk, Stuff for oil and temp indicators on the dash, fan control, things like that The problem is I have weak spark off one coil and NO spark off the other. I have checked and rechecked the signal, ground, and power to the coil and they are all working properly. Since i tested the coil that cannot be it. My only thoughts were that timing was off or CAS CPS sensors were dead. I verified the timing with a new belt and correct alignment. It changed the cranking by eliminating a cough that used to happen every 4 or 5 cranks. So im down to thinking valves, or sensors. Id like to take another compression reading, and try the test sensors What do you think?? Thanks for the reply nipper Quote Link to comment Share on other sites More sharing options...
nipper Posted June 21, 2006 Share Posted June 21, 2006 thanks for the history. Thats what i would do to, a wet dry compression test, and the sensors. Since you have a running car to play with, test those sensors first so you know what to look for. Was this engine running before hand? any chance the ecu is fried? nipper Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 21, 2006 Author Share Posted June 21, 2006 Well i bought the engine from a reputable guy that promised me it ran before he pulled it. Haha yes the ECU part of the story i didnt convey. the first ECU i got was sold to me wrongly and was for a 2000 Version of the SOHC which is MAP based. I have the 99 version which is MAF based so no dice on the ecu. I then bought another one from a punk on NASIOC who overcharged me and sold me a California version so then i bought a 3rd one from a used parts dealer who pulled a non california 99 SOHC ecu from a running car. So unless my luck is as bad as it possibly can be, it should be ok PS you mentioned a wet dry compression test? whats the diffrence between wet and dry...other than the obvious :-p Quote Link to comment Share on other sites More sharing options...
nipper Posted June 21, 2006 Share Posted June 21, 2006 wet and dry (with all plugs out and air intake junk removed), thats how you tell if you have a ring issue or a valve issue. You take a dry test (assuming low or out of balance numbers). Then you squirt/spray oil in the cylinders and do a wet test. If you have bad rings the numbers will go up. If you have a bad valve everything will stay the same. If there is no change everything is good if you have good numbers. if all the numbers are low and no change on the wet test look at the valve timing. nipper Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 21, 2006 Author Share Posted June 21, 2006 Cool...ya learn something new everyday. How much oil do you spray in? What range should be compression readings be? Thanks for the super quick replies Quote Link to comment Share on other sites More sharing options...
nipper Posted June 21, 2006 Share Posted June 21, 2006 Cool...ya learn something new everyday. How much oil do you spray in? What range should be compression readings be? Thanks for the super quick replies compression test are a bit quirky, your looking for balance as opposed to high numbers. you can have 4 cylindes at 122 125 127 120 and thats fine. You can have 160 130 150 180 and something is wrong. Anything below 100 is a tired engine. Also 120 60 128 50 means a bad head gasket of bad valve timing on a subaru. No more then 10% differnce between cylinders (usually if numbers are bad they are really bad). Wet tests are a little tough due to the boxer design. You may have to take it twice to get the right numbers in order to spread the oil around. Normally 120 60 50 128 means a bd HG on an inline engine. Make sure the car is on a charger or jumped as starter rpm will affect the readings. nipper Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 21, 2006 Author Share Posted June 21, 2006 thanks nipper ill do this on the weekend and post back Quote Link to comment Share on other sites More sharing options...
tcspeer Posted June 22, 2006 Share Posted June 22, 2006 I removed this post, sorry I just repeated something that was already covered. Quote Link to comment Share on other sites More sharing options...
nipper Posted June 22, 2006 Share Posted June 22, 2006 I removed this post, sorry I just repeated something that was already covered. we all do that at some time, or the net hiccups and screws us up :-p nipper Quote Link to comment Share on other sites More sharing options...
ShawnW Posted June 22, 2006 Share Posted June 22, 2006 Are you sure you have the right crank gear installed? Theres one with 6 ears and one with a ton of little teeth. They must match the cam and ECU that they belong with. In 99 a SOHC would have a 6 ear one. In 2000 the MT has one kind and AT has the other and from there newer is all tiny tooth ones. Of course Subaru tosses a few jokers in here and there to mess with "rules" but these are pretty safe. 1 Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 22, 2006 Author Share Posted June 22, 2006 crank gear is the one in the middle on the crankshaft behind the acc. pulley? im not sure what 6 ear means.....Any pictures? they would be worth a thousand words Sorry im still learning the exact jargon Quote Link to comment Share on other sites More sharing options...
nipper Posted June 22, 2006 Share Posted June 22, 2006 i THINK he means by ears and teeth, is that these are waht pass by the crankshaft position sensor and generate the pulses for the ecu. If the ecu is looking for 6 heartbeats and sees 30 it is not going to run, same the other way around. nipper DO you have a haynes manual? Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 22, 2006 Author Share Posted June 22, 2006 That makes total sense and would be a great thing to check Well i have a haynes manual for the earlier subarus...do they make them for the later ones? I have a friend who has been printing stuff out of the subaru manuals...he has a subscription to one of those services Can i get a haynes manual for the 99? Quote Link to comment Share on other sites More sharing options...
nipper Posted June 22, 2006 Share Posted June 22, 2006 That makes total sense and would be a great thing to check Well i have a haynes manual for the earlier subarus...do they make them for the later ones? I have a friend who has been printing stuff out of the subaru manuals...he has a subscription to one of those services Can i get a haynes manual for the 99? the latest covers to 1998, i fthe 2.5 is a dohc then it will wor out for you, if its a sohc it might not. nipper Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 22, 2006 Author Share Posted June 22, 2006 yeah its a SOHC...i dont think i would even work with a DOHC this much....the SOHC first was in the 99 forester and 2.5 RS using a MAF based system. In 2000 all 2.5 vehicles went to the 2.5 SOHC and switched to the MAP based System Just so happens i have the "rare" engine...fun for me... Quote Link to comment Share on other sites More sharing options...
nipper Posted June 22, 2006 Share Posted June 22, 2006 yeah its a SOHC...i dont think i would even work with a DOHC this much....the SOHC first was in the 99 forester and 2.5 RS using a MAF based system. In 2000 all 2.5 vehicles went to the 2.5 SOHC and switched to the MAP based System Just so happens i have the "rare" engine...fun for me... someone always has to be diffcult nipper Quote Link to comment Share on other sites More sharing options...
simbey1982 Posted June 22, 2006 Author Share Posted June 22, 2006 Anyway i just want to say thanks for your help and ill post updates as soon as i find all this stuff out Cory Quote Link to comment Share on other sites More sharing options...
nipper Posted June 22, 2006 Share Posted June 22, 2006 Anyway i just want to say thanks for your help and ill post updates as soon as i find all this stuff out Cory as much as i am against digital manuals, you may want to get one off ebay to give you a better idea of whats what on your engine. nipper Quote Link to comment Share on other sites More sharing options...
ShawnW Posted June 23, 2006 Share Posted June 23, 2006 i THINK he means by ears and teeth, is that these are waht pass by the crankshaft position sensor and generate the pulses for the ecu. If the ecu is looking for 6 heartbeats and sees 30 it is not going to run, same the other way around. nipper DO you have a haynes manual? EXACTLY what I mean. If you have both engines and take both crank pullies off the engines you will see what I mean, sorry no picture at the time. All that is really important is to use all the related parts from 1 engine. I believe but I havent tried it before, that you COULD use the upper cam gears off a DOHC on a SOHC and the DOHC crank gear and have an engine run right...and that you would also use the intake manifold and wiring from whatever matches the CAR as well. This would trick the engine into thinking it had quad cams. If it works on a 2.5-->2.2 conversion I dont see why it wouldnt here. Quote Link to comment Share on other sites More sharing options...
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