Engine is running ruff and sometimes wont start 02 forester

[slipknot51]

So i know that this is not the subaru forester forum but i feel that people on her are more comfident in this forum then the other forums and I figure that you guys might be more help since i got alot of help with my Legacy .
So i have a Friend that has a Subaru forester that came in to the shop with the problem with wheel bearing's which he put new ones in and when he got done for some reason the car has seemed to go all out of wack. There is now intermediate spark on cylinder 3 and 4 it still is a waste spark ignition system and he told me that there is 4 wires that go to the coil pack he said that at one of the pins he is getting the full battery power and another pin he has ground but he really didn't know what the other two pins are used for my guess is that they got to the transistersr in the ecm to ground out 1/2 and 3/4 coil's. he also tried to change out the crank and cam sensor to see if that made any difference and same deal. The car does have brand new plugs and wires as of febuary of this year. Also for s and g's i was wondering how the newer subaru ecu's control spark and fuel I know that it is normally that crank controls spark control and that cam controls fuel control he also was wondering if maybe a knock sensor would have any effect on the way the system is working. Oh i forgot to mention that there are no cel on. Again Thanks for your time Guys.

[Legacy777]

So it ran fine before it came into the shop? Was any work or anything done to the front end of the car while in the shop? How long was it in the shop? Is the battery fully charged up?

[slipknot51]

The car was from what i was told running fine before it came into the shop. While it was in the shop they did wheel bearings on the front of the car both driver and passanger side. It has now been in the shop for about 2 weeks now while they have been testing stuff. The battery is a newer battery and the battery is fully charged when they checked it with a dvm at 12.74v
I told them to check out with wiring from the ecm to the crank and cam sensors to see if they might have high resistance in the wires that might cause an issue with a weak signal going to the ecm. They have checked the rings that are conected to both the crank and cam and there was no damage to them.

[Legacy777]

I would agree it'd be wise for them to check the wiring from the ECU to the crank/cam sensors as well as some of the other critical sensors. They can d/l the service manual from me which has the wiring info needed.

http://bbs.legacycentral.org/viewtopic.php?f=12&t=14485

[slipknot51]

i was also kind of wondering about this myself he said that the coil pack on the forester was a 4 wire as well i know on the 90-94 legacys they used an ignitor and the coil was a 3 wire setup 1 main power to the coils and 1 ground for 1/4 and 2/3. If i had to take a educated guess i would say in the forester 4 wire that they gave power and ground individually to coil's 1/4 and 2/3. But thats just my guess unless they are using it to referance timing of spark idk.

[slipknot51]

Figured out what the problem was He did check the wiring for resistance and there was no excessive resistance in the wires so he goes and checks the timing belt and i guess that timing belt tensioner was bad and was causeing the belt to become loose and skipping on the cam gears and causeing the issue so i think he is dealing with more of a head and valve issue but he is going to check it with a clt to see if there is any major damage to the valves. The reason he did check the timing belts before is because there was another shop that replaced the belt last november. Other then that i was still wondering about that wiring it seems intresting that they have them 4 wires now but im guessing it was for grounding.

[Legacy777]

Glad he figured out the problem. Hopefully there's no damage to the valves.

[slipknot51]

Yeah the Clt testing went good no excessive leakage on the cylinders all of them passed so he is just going to be putting in a new timing belt and tensioner in it and its going to be down the road motors.