[thetraveler]

how would you check the timing belt to see if it was installed correctly?

 

[CSFiend]

Pull the timing covers and verify the timing marks are all aligned.

Are you having a problem, or just curious?

edit: pulling the info from your other post:

What would happen if the timing belt on one side was foo two teeth?
Would the car run at all? would there be damage to the engine?
2002 Sub outback 2.5 engine

Two teeth off on a cam gear shouldn't be enough for the valves to meet the piston. If it started and ran, I'd expect it to run very poorly.

 

[thetraveler]

i did the timing belt 2 months ago. the car runs good till it worms up then it seams to have an intermittent miss. only when your cursing. not when your accelerating.

 

[CSFiend]

i did the timing belt 2 months ago. the car runs good till it worms up then it seams to have an intermittent miss. only when your cursing. not when your accelerating.

I believe a stumble at cruise is usually related to ignition components. When was the last time you replaced plugs or wires?

 

[nipper]

i did the timing belt 2 months ago. the car runs good till it worms up then it seams to have an intermittent miss. only when your cursing. not when your accelerating.

Well maybe if you stop swearing at it ....

 

[thetraveler]

Changed plugs and wires 2 weeks ago also changed o2 sensors front and back

 

[johneracer]

My opinion. Timing is fine, there would be no change hot/cold if the timing is off. Car would run like crap at all times. Sounds like fuel issues or bad o2 sensor. I remember on my honda during acceleration fuel was scheduled according to fuel map. Cruising only o2 sensors provide feedback to the computer. If they are bad that would explain the problem. I believe subaru works the same but I have not worked this problem before so I am not sure.

 

[johneracer]

Also use only Oem o2 sensors...aftermarket never worked good for me

 

[thetraveler]

local dealer said it was the timing off 2 teeth. also said new oem o2 sensor was bad. on the heat side. reading were all over. i don't see how it could run fine then have intermittent problem?

 

[thetraveler]

Denso 234-5003 Oxygen Sensor


Denso 234-4132 Oxygen Sensor

these are the sensors that i installed

 

[johneracer]

local dealer said it was the timing off 2 teeth. also said new oem o2 sensor was bad. on the heat side. reading were all over. i don't see how it could run fine then have intermittent problem?

Really???? I find that hard to believe. If the timing is of by 2 teeth (that's a lot) car would run like crap at all times. I had dealers tell me BS before so be aware. Just change the 02 that is in question or get a second opinion. That's a total load of crap...

 

[thetraveler]

they had the car for 3 days to figure it out. i did the timing belt job and took it back to the garage that i purchased it from and was told there was nothing wrong with the engine? the dealer said that they first thought it was timing then said no timing was ok. after 3 days told me it was off 2 teeth. i just don't understand how. i would think it would be some sensor or fuel problem.

 

[thetraveler]

if the o2 sensor was bad on the heat side wouldn't it show a code?

 

[thetraveler]

he also said something about cleaning the throttle body said it was all gummed up.

 

[cardoc]

Fuel trim is calculated every time the car is started based on barometric pressure, air temperature, MAP sensor and AF sensor feedback to the ECM. Once the ECM decides on a closed loop fuel map, it uses that map in all closed loop operation until something occurs that demands a change. At that time, it goes back in to a learning mode.

Cruising, or cursing either one, will result in closed loop map trims after the engine reaches 172F or higher. When you accelerate, the ECM switches to open loop to provide fuel as needed based on the engine load calculations at the time. Once you return to cruising, the ECM returns to closed loop and continues to use the previous trim map. Until, it detects a change in the load under cruise at which time it will return to a learning state for a new map.

If the computer is changing its map in quick succession over short periods of time, it starts looking for the issue causing the learning operations. When it finds the source, or system area of concern, the MIL is lit and the code is stored.

If the heater circuit in the AF sensor or Oxygen sensor is bad, it will set a code for the heater circuit in the offending sensor. Its a hard code and is always correct. Any sensor heater circuit code pops up, change the sensor. If there isn't a heater circuit code, it could be a weak heater, but unlikely. When the heater fails or starts to fail, the resistance increases and the ECM sees the resistance change.

If the engine runs smooth when its cold, then rough when it warms up, it can be a vacuum leak, AF sensor or connection issue, weak fuel pump or clogging filter, weak coil, bad grounds or a weak battery. The ECM enriches the fuel for warm up, then reduces to maintain stoichiometric as temperature increases. Anything that effects stoichiometric mixtures will illuminate the MIL for too lean or too rich. If its a weak fuel pump not supplying enough fuel, it would be lean. Same with a filter problem. A weak battery or poor output of the alternator will cause multiple issues and the computer may not be able to determine the cause of the problem, so no MIL.

Check the amperage output of the battery. Check ground connections and conductivity. Check the alternator output, and this is only conclusive with a good battery and grounds. If the battery and alternator check out good, then go to the coil and sensors. Check fuel pressure cold, then after running a while. Check the effectiveness of the fuel pressure regulator. Check for vacuum leaks with the engine cold then again when it reaches operating temperature.

As I posted on your other thread, the engine would run unbalanced regardless of cold or hot. Depending on the rotation of the offending cam, the timing on that cam would be either retarded or advance in comparison to the opposing cam which would make for a really rough running engine or no start at all. It would also be dependent on which cam. One cam has the cam sensor and this sensor determines fuel injection cycles so one side of the engine will be getting fuel early or late. Its not the timing if it starts and runs smooth cold. They are overlooking something and its probably going to be simple with a few :1pat: when they find it.

 

[cardoc]

Checking the AF sensor: With an Ohm meter, check resistance between pin 5 and 2. If resistance is less than 10 Ohms, its good, greater than 10 Ohms, replace it.

A poor connection at the harness plug for the sensor, or oil deposits within the connection will cause problems with current flow.

If a "universal sensor" is installed, replace it. Don't bother testing it. Install an OE fit replacement Denso.

Attached is a diagram with pin numbers for each plug/harness.

 

[johneracer]

Fuel trim is calculated every time the car is started based on barometric pressure, air temperature, MAP sensor and AF sensor feedback to the ECM. Once the ECM decides on a closed loop fuel map, it uses that map in all closed loop operation until something occurs that demands a change. At that time, it goes back in to a learning mode.

Cruising, or cursing either one, will result in closed loop map trims after the engine reaches 172F or higher. When you accelerate, the ECM switches to open loop to provide fuel as needed based on the engine load calculations at the time. Once you return to cruising, the ECM returns to closed loop and continues to use the previous trim map. Until, it detects a change in the load under cruise at which time it will return to a learning state for a new map.

If the computer is changing its map in quick succession over short periods of time, it starts looking for the issue causing the learning operations. When it finds the source, or system area of concern, the MIL is lit and the code is stored.

If the heater circuit in the AF sensor or Oxygen sensor is bad, it will set a code for the heater circuit in the offending sensor. Its a hard code and is always correct. Any sensor heater circuit code pops up, change the sensor. If there isn't a heater circuit code, it could be a weak heater, but unlikely. When the heater fails or starts to fail, the resistance increases and the ECM sees the resistance change.

If the engine runs smooth when its cold, then rough when it warms up, it can be a vacuum leak, AF sensor or connection issue, weak fuel pump or clogging filter, weak coil, bad grounds or a weak battery. The ECM enriches the fuel for warm up, then reduces to maintain stoichiometric as temperature increases. Anything that effects stoichiometric mixtures will illuminate the MIL for too lean or too rich. If its a weak fuel pump not supplying enough fuel, it would be lean. Same with a filter problem. A weak battery or poor output of the alternator will cause multiple issues and the computer may not be able to determine the cause of the problem, so no MIL.

Check the amperage output of the battery. Check ground connections and conductivity. Check the alternator output, and this is only conclusive with a good battery and grounds. If the battery and alternator check out good, then go to the coil and sensors. Check fuel pressure cold, then after running a while. Check the effectiveness of the fuel pressure regulator. Check for vacuum leaks with the engine cold then again when it reaches operating temperature.

As I posted on your other thread, the engine would run unbalanced regardless of cold or hot. Depending on the rotation of the offending cam, the timing on that cam would be either retarded or advance in comparison to the opposing cam which would make for a really rough running engine or no start at all. It would also be dependent on which cam. One cam has the cam sensor and this sensor determines fuel injection cycles so one side of the engine will be getting fuel early or late. Its not the timing if it starts and runs smooth cold. They are overlooking something and its probably going to be simple with a few :1pat: when they find it.

What he said. Bottom line it's not the timing

 

[thetraveler]

how would you change the timing on one side after the belt was on ? thanks for all your help

 

[Timberwolf99]

You can't it would require a retime, eg redo the timing belt and the associated work to get at it.

 

[CSFiend]

how would you change the timing on one side after the belt was on ? thanks for all your help

I'm not sure how to say this in a clearer way...

Again.... it's not the timing belt. Cardoc posted a plethora of things to check. I'd encourage you to take a look at it again.