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1.6 Ecoboost surge

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3
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Location
Georgia
#1
Hey, First time doing a timing belt on an ecoboost. Car is back together running and driving, I had the ac headlights, and radio on when I first started the car not knowing I needed them off for idle relearn. I have an issue with idle surge right now I tried to drive it out but it has gotten worse, reading the fuel trims im at almost 20% on long term so i checked for a vacuum leak everywhere with brake cleaner but found nothing. When driving the car it is fine under any throttle but at idle it surges and tries to die. (will in gear). Just trying to see if anyone has had this same issue and what did they do to fix it or where I should start.
 


Intuit

3000 Post Club
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South West Ohio
#2
What codes are present before clearing them?
Clear them and tell us what comes back.
 


OP
J
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3
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2
Location
Georgia
Thread Starter #3
I didn't just do the timing belt I did it in addition to the main issue. The head gasket, I replaced it because I had a misfire on 2 and 4 and it was drinking coolant. Had a code for cylinder 2 and cylinder 4 misfire. After replacing the head gasket and timing belt I have had no codes come back. Just did all the relearns through forscan but nothing has helped the idle yet. Same issue, just surging at idle fine when you drive it. Im going to drive it to the shop I work at this week and drive it with live data and see if i can figure out why fuel trims are so high. If I can't Im going to pull the timing cover and reverify cam/crank and harmonic balancer position.
 


OP
J
Messages
3
Likes
2
Location
Georgia
Thread Starter #5
What are the VCT-I AND VCT-E readings at idle when warmed up?
they are both +-1% or degree. I used the Zeus scanner at the shop and watched spark advance at idle, it is jumping all over the place while the engine surges. It goes steady at any constant rpm when I'm on the gas. I used the functional test menu where I would alter timing advance with the scanner and when I was at idle warmed up and retarded the timing to -10 degrees constant and the surging went away. I think this means that the harmonic balancer with the reluctor hole is off a couple degrees. I am going to pin the cam phasers and crank and pull the balancer off and try again. I will update yall with anything I find.
 


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