Timing Advance with EST Disconnected
Thread Starter
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Joined: May 2021
Posts: 97
Likes: 8
From: Lee County, Florida
Timing Advance with EST Disconnected
Having a weird issue, 85, 165 swapped $6e. EST connected and at low idle, the timing will randomly jump from 6 btdc to 10 or 12 or so at random, enough to cause the car to idle hunt. My timing chain is a brand new summit double roller, tested pickup coil and primary and secondary on my coil, all passed with flying colors, distributor doesn't really look like it has any more play then when I last checked? Anything else I'm missing here, can a aftermarket or bad ICM cause this issue, I warranted it once already for this issue and it seems to not have changed, I think it's a Duralast DR-124 unit. Any advice or anything I'm lacking to check, the chain I installed I believe to be very high quality in comparison to the stock, so I very much doubt that's the issue
Thread Starter
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Joined: May 2021
Posts: 97
Likes: 8
From: Lee County, Florida
Right I know that's normal, and that still functions, but at 400-500 rpm it's jumping at random and then coming back down, weirdly enough if I give it some rpm below 1500 it seems to stabilize.
Melting Slicks
Joined: May 2014
Posts: 2,895
Likes: 592
From: New Port Richey FL
Could be a sporadic Knock sensor, you can use a scan tool to check the system or since you have a timing light tape the trigger and prop up the light on the scale. Take a long 3/8 extension and place it on the head bolt above knock sensor and give it a few taps with a hammer the timing should jump in time with taps.
Also just as a point of common failure inspect the balancer for loose rubber or slippage on the hub
Also just as a point of common failure inspect the balancer for loose rubber or slippage on the hub
Thread Starter
Advanced
Joined: May 2021
Posts: 97
Likes: 8
From: Lee County, Florida
Could be a sporadic Knock sensor, you can use a scan tool to check the system or since you have a timing light tape the trigger and prop up the light on the scale. Take a long 3/8 extension and place it on the head bolt above knock sensor and give it a few taps with a hammer the timing should jump in time with taps.
Also just as a point of common failure inspect the balancer for loose rubber or slippage on the hub
Also just as a point of common failure inspect the balancer for loose rubber or slippage on the hub
