Topic: whats the difference

[renegade_obs]

newbie here. so for the last couple years ive been trying to fix my 98 OBS with a 2.2L . i have since given up and am looking for something to swap in for cheap. the only problem is that the only motors in my price range are all out of early 90's suby's so whats the difference between a 2.2 out of a 91 and the 2.2 in my 98?

[seat safety switch]

The phase 1 and phase 2 EJ22s are fairly different internally but Subaru's famous lego engineering pays off for us anyway.

Phase 2 starts in MY97. There are some tiny revisions in MY93 but nothing to write home about. Phase 2's biggest change is that it has a higher compression ratio which also causes it to become an interference motor. Some emissions stuff pops up (EGR in California is the big one) and the power and torque improves as well as the torque delivery.

As for interchange, as always all EJs will bolt up just as well as any other. Some phase 2s (I want to say all but I'm not sure) go to single port exhaust which necessitates the use of a phase 2 header so you might have to get a dual port header in order to run a phase 1 head in a phase 2 car. That could be difficult with an OBS as they have a special header for clearance but I think OBX made a dual port header that's available - otherwise try to find a junkyard unit that's good enough or see if the EJ25 OBS header fits. Maybe you can even get away with swapping the heads over if that's not the source of the problem on the 98. What was the problem with the original engine?

ECU-wise it looks like (from quick googling) that you need to swap the intake manifold and sensors over to keep the ECU happy (run a phase 2 intake manifold on a phase 1 engine) and you should be good.

Evil genius solution: If the shortblock is nuked one thing I've always wanted to try is an EJ25 DOHC shortblock with EJ22 heads on it. Then you'd get a massive compression ratio and, with a DOHC EJ25 ECU of the right year, you could reuse the existing intake manifold and sensors while raising the redline. Good luck finding a good EJ25 shortblock for the same as a phase 1 EJ22 though.

[renegade_obs]

the issue with the car was that about 2 years ago it started to develop a hesitation. it would idle fine and once you got the rpms above 2500 it was fine but between that it would try to bog and have no power at all. the only way i could at that time get it up to 2500rpm was to tap on the throttle really lightly and quickly and it would slowly pick up rpms. it threw a miss fire code on cyl 4. i got that cleared and when it went in to three point the miss fire code showed up on cyl's 1 & 2. now from what ive researched if its going to miss on more than one cyl its supposed to miss on 1&3 or 2&4. so the miss is kind of randomating it self. since then its sat and id get it fired up every month or so just to keep things some what lubricated and every now and then see if i could make any head way on the problem. the hesitation got to the point where it was too dangerous to drive. since parking it ive replaced the fuel filter, fuel pressure regulator, plugs & wires cleaned the TPS & IAC. run seafoam through most of the vacuum lines. done a fuel pressure test (tester was put on the hose from the fuel filter going to the hardline that runs under the intake. pressures were * vacuum hose attached to regulator 35-38 * vacuum hose detached from regulator 39. those were the numbers i got on the gauge we used. at that point it would still at least fire up and idle. then i replaced the vacuum line and T fitting that goes from the intake to the fuel pressure regulator and some other kinda redish brown piece on the passenger side shock tower. but in dooing so i deleted this little round thing that looks like its white plastic with foam in the line that goes to the piece in the shock tower. the next day i tried to fire it up and i couldnt get it to run. so i put the original vacuum hose with all the proper pieces back in and it still wouldnt fire up. on cranking every now and then it tries but it dosent quite fire enough to get it running at idle, it just stumbles momentarily to make me think its gunna fire up. .

heres word for word the list of things three point motors managed to check when i had it in to them.
*scanned car - came up miss fire on 1&2 checked plugs, wires, and coil they were ok. pulled out o2 sensor to check if exaust was plugged, it wasnt. checked throttle plate checked EGR operation checked MAF sensor checked Oxygen sensor. will contact coustmer after talking to subaru expert. (in other words... they had to call subaru teck support back east)

so now im stuck with it not running at all. but when i could get it fired up it would idle fine, it would rev fine once above 2500 rpm but between idle and 2500 rpm it wouldn't wanna go, and if you dropped below that 2500 rpm then your back to square one.

did a compression test. here are my results. cyl1. 137 cyl2. 105 cyl3. 137 cyl4. 83... the compression test was done cold as im trying to diagnose the other issue of not running. any thoughts on whats going that is causing my low compression? and how it would effect it running?

and since then, if i put my fuel pressure tester inline between the fuel filter and hardline on the motor and leave it all it will do is crank. but if i hold the pressure release open on the gauge while its cranking, it does stumble as if its going to fire up.

any ideas?

[renegade_obs]

i i do have a line on a 99   2.5 forester motor but the guy says "It has a noisy tick when it runs, sometimes it delays before it switches into higher gears, so it will rev high before shifting, especially going up hills. It uses more gas then it use too." but its a complete car for $900
i figure the shifting could b e the start of the transmission slipping but i dont know about the tick in the motor.