el_freddo Posted October 28, 2023 Share Posted October 28, 2023 The only timing issue it could be is skipped teeth on the cam belt. The ECU sets the spark timing. Valve timing doesn’t change once the cam belt is correctly setup. Cheers Bennie Link to comment Share on other sites More sharing options...
idosubaru Posted October 29, 2023 Share Posted October 29, 2023 On 10/27/2023 at 8:40 PM, ThosL said: probably timing issues as the compression is tops. On 10/26/2023 at 7:39 PM, ThosL said: However it's clear to me that bent or malfunctioning valves are the reason for the hesitation and sputtering on the other head. How did you change your mind so quickly? The timing tensioner can fail. They’ll start moving around/bouncing vigorously during driving or cold start. If you take the cover off and watch it you’ll see it. If it’s aftermarket or was compressed too quickly during reinstallation, that may have been its demise. Pull the drivers side cover and watch it at start up and when giving it throttle. Link to comment Share on other sites More sharing options...
ThosL Posted October 29, 2023 Author Share Posted October 29, 2023 6 hours ago, idosubaru said: How did you change your mind so quickly? The timing tensioner can fail. They’ll start moving around/bouncing vigorously during driving or cold start. If you take the cover off and watch it you’ll see it. If it’s aftermarket or was compressed too quickly during reinstallation, that may have been its demise. Pull the drivers side cover and watch it at start up and when giving it throttle. To tell you the truth, I don't know what the issue is and I'm going to have the mechanic try to figure it out this week. He went over the pulleys, etc. and only replaced what was needed. Link to comment Share on other sites More sharing options...
idosubaru Posted October 30, 2023 Share Posted October 30, 2023 7 hours ago, ThosL said: To tell you the truth, I don't know what the issue is and I'm going to have the mechanic try to figure it out this week. He went over the pulleys, etc. and only replaced what was needed. Okay so your were just guessing? Read all the codes check connectors removed during removal Prob bent valves. Hopefully you’re lucky and it’s the tensioner. Removing and compressing it for reinstall can compromise them. The bent valve EJs I’ve repaired myself, it can be hard to tell if the valves are bent. Best to just replace them all than get fooled and leave a bent one there. They don’t always bend in a visually obvious way. It is interesting if it’s true you’re saying you have good compression. The valve guide could be damaged or the valve is hanging in the guide, causing good compression but not fully opening. Link to comment Share on other sites More sharing options...
1197sts Posted November 2, 2023 Share Posted November 2, 2023 A quick leak check on the valves will tell you which ones are bent. As others have mentioned it is not unusual for all of them to be bent. Some will be obvious, some not so much. I have made this mistake myself, its no fun to pull the engine to replace the valves I missed the first time. As GD mentioned just replace them all. Link to comment Share on other sites More sharing options...
ThosL Posted November 6, 2023 Author Share Posted November 6, 2023 The Subaru is running fine as is. I'll have the mechanic check compression again, wouldn't that be enough to determine problem valves? Link to comment Share on other sites More sharing options...
idosubaru Posted November 7, 2023 Share Posted November 7, 2023 20 hours ago, ThosL said: The Subaru is running fine as is. I'll have the mechanic check compression again, wouldn't that be enough to determine problem valves? Leak down test is a far better test in this case. Link to comment Share on other sites More sharing options...
ThosL Posted November 10, 2023 Author Share Posted November 10, 2023 There are no performance issues at this point, the engine and car is running better than ever, there would be no point for tests. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now