[BFDHOMER]

1996 155 hp & 1999 165 hp engine swap. vehicle will not start are the computers diff?

I recently swapped a 2.5 liter 1996 155 hp engine into my 1999 OB wagon. After the install the vehicle would not start. It turns over and backfires however will not start. Vehicle is getting fuel and spark.
We swapped the intake and knock sensor everything else plugged right in. Can anyone help me figure out why this won't work.

 

[avk]

The ignition timing may be wrong due to year-to-year differences between cam and/or crank sprockets, assuming the timing belt was installed correctly. The sprockets should interchange, but please check with those who have actually done it.

 

[scoobythesubie]

I recently swapped a 2.5 liter 1996 155 hp engine into my 1999 OB wagon. After the install the vehicle would not start. It turns over and backfires however will not start. Vehicle is getting fuel and spark.
We swapped the intake and knock sensor everything else plugged right in. Can anyone help me figure out why this won't work.

I agree with the other guy. With the limited info you've given, I'd say the timing is off.

 

[BFDHOMER]

Does that mean I need to change the coil?

 

[BFDHOMER]

Or how do you change the timing then?

 

[avk]

Just compare the triggering teeth on cam and crank sprockets between the two engines. If they are arranged differently, swap the sprockets.

 

[canubaru]

more info please!

how many miles on the ''new''engine?
any known history?
did you replace the timing belt before you installed the engine?
did the engine come from a parts yasrd or an individual?
was the engine in good operating condition when you bought it?
did you hear it run?

it is not the cam sprockets, (unless some one swapped out the factory sprockets before you bought the engine.)
it is not the crank sprocket, (unless some one swapped out the factory sprocket before you bought the engine.)
it is not the ECU computer. if the old engine ran on the computer the new engine will run on the computer.

if you are sure you have spark and fuel it has to be ....
timing (fires but at the wrong time or injects fuel at the wrong time)
compression (bad rings, valves or severely bad head gasket.)
bent valves due to a bad / busted / jumped timing belt (no compression)

remove the cam timing belt covers, 3 bolts each side, and turn the engine by hand until the cam timing marks line up. do all 4 cams line up correctly?

does the crank pulley wobble when you try to start the engine?

it sounds like you are pretty new to this stuff. check the timing as indicated above.
since you lack the experience to track this down, after you check the timing, i would suggest swapping the cam and crank sensors off of your old engine. just a few minutes of work for each and you KNOW they were working on the other engine. what happened to your old engine?

more info please.

NOT the ARROWS, NEVER the ARROWS.
timing diagram below. you can not check the crank timing with out removing the crank pulley.

 

[BFDHOMER]

My dad is an old gearhead that has done 3 Subie motors for me over the years I am just the muscle that helps him. The motor I am installing was running in a vehicle that was t-boned. The engine has new plugs, timing belts, water pump, head gaskets manifold gaskets and oil & filter. I talked with another Subie mechanic and he recomended changing the cam & crank sensors. Hoever he said to buy new ones because they usually break during removal. Thank's for the info I will let you know what happens if you think of any other ideas please let me know.

 

[canubaru]

if the info you provided is accurate, 96 DOHC ej25 and a 99 DOHC ej25 OUTBACK then there is no need to swap the cam and crank sprockets. foresters were SOHC phase 2 engines in 99 and they had different sprockets. and starting in 00 ALL ej25s were SOHC phase 2 engines.

and if this is your dad's 3rd subaru engine, there is much less reason to think that the timing is off. although, as humans, we do make mistakes some of the time.

and there is always the possibility that the timing jumped a tooth or 2 on the first start attempt. this is more likely if the tensioner was not replaced. so check the cam timing marks. it is easy to do .

to repeat , 4 things are needed to start:
fuel
spark
air
compression.

have you done a compression test??

i would check for each of the above.
i would double check that every thing is plugged in.
i would double check the fuel lines to make sure you got them in the right order on the metal lines on the intake.
and check the compression .