Timing chain position inspection
On The Tree
Joined: Feb 2025
Posts: 107
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From: England
Presume you’re worried about condition, if so not really, you could check backlash in chain by turning crank and watching cam movements , but not very effective & it does not tell you condition of gears.
If are meaning the cam timing, then it would be valve lift closing at crank angle with dial gauge.
If are meaning the cam timing, then it would be valve lift closing at crank angle with dial gauge.
12 Second Club
Joined: Apr 2015
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From: West Coast
On The Tree
Joined: Feb 2025
Posts: 107
Likes: 36
From: England
Have a read of this
https://ls1tech.com/forums/generatio...ad-center.html
But it would be easier to just pull the cover and check tbh
TECH Enthusiast
Joined: Aug 2021
Posts: 507
Likes: 190
Split Overlap Turn the crankshaft with a valve cover off, watch the rocker arms move, AND after the lifters are pumped up.
You will find one cylinder with its valves "part" opened (Overlap).
Mark the Dampner in four equal places, one which is TDC 0
That cylinder should have the rocker arms/valves at equal distance with a Split Overlap camshaft (most common)/
When one of the four marks matches the TDC 0 pointer
You will find one cylinder with its valves "part" opened (Overlap).
Mark the Dampner in four equal places, one which is TDC 0
That cylinder should have the rocker arms/valves at equal distance with a Split Overlap camshaft (most common)/
When one of the four marks matches the TDC 0 pointer
TECH Resident
Joined: Jun 2013
Posts: 814
Likes: 231
From: Nebraska, The Good Life
The chain would have to be unbelievably loose/stretched for the chain to have skipped a tooth. And if it had, the crank and cam sensors would be causing codes in the ECU like crazy.
I would think a chain would break long before it would stretch enough to skip.
I would think a chain would break long before it would stretch enough to skip.
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Thread Starter
Teching In
Joined: Dec 2020
Posts: 43
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From: Huntsville, AL
Ok. I'm getting a flashing CEL with no codes, and I'm having trouble diagnosing the issue. Maybe this one should be crossed off my list. Sounds incredible.
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Thread Starter
Teching In
Joined: Dec 2020
Posts: 43
Likes: 1
From: Huntsville, AL
Rough idle, random misfire, etc. This all started after I changed the oil pan gasket. I took the timing cover off to do that which required that I remove the crank pulley. Wondering if I the chain could've slipped during that process without me knowing it.
TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
You have other issues. You might just need plugs and/or wires.
Thread Starter
Teching In
Joined: Dec 2020
Posts: 43
Likes: 1
From: Huntsville, AL
Based on what I've done so far, I don't think I have any vacuum leaks and my MAF sensor seems to be working fine. So, my near term plan is to check compression then change my plugs, wires and o2 sensors. Then, I'll go through the crank relearn procedure since I never did that after my engine swap. I'll report my progress back to this thread. Fingers crossed.
TECH Senior Member
Joined: Jun 2016
Posts: 22,301
Likes: 3,625
From: Central Cal.
Yeah I forgot about the MAF sensor. It might be "working" BUT dirty.
Get some MAF cleaner from the parts store. It might help things too.
Also, get a bottle of Chevron Techron and put it in with the next full tank of fuel. I'm not normally an additive junky, but this stuff cleans fuel systems.
Get some MAF cleaner from the parts store. It might help things too.
Also, get a bottle of Chevron Techron and put it in with the next full tank of fuel. I'm not normally an additive junky, but this stuff cleans fuel systems.
Thread Starter
Teching In
Joined: Dec 2020
Posts: 43
Likes: 1
From: Huntsville, AL
Yeah I forgot about the MAF sensor. It might be "working" BUT dirty.
Get some MAF cleaner from the parts store. It might help things too.
Also, get a bottle of Chevron Techron and put it in with the next full tank of fuel. I'm not normally an additive junky, but this stuff cleans fuel systems.
Get some MAF cleaner from the parts store. It might help things too.
Also, get a bottle of Chevron Techron and put it in with the next full tank of fuel. I'm not normally an additive junky, but this stuff cleans fuel systems.
I'll do that with the Techron. I've seen the same advice in other places too.
Joined: Apr 2006
Posts: 3,931
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From: Grand Rapids, Michigan
I knew as soon as you posted that it was a Silverado. Forget everything else you're doing and get a scanner on it that can do a crankshaft variation learn. It will most likely fix your problem. It is very common for Silverados to have unexplained misfires with no CEL. I have diagnosed this many, MANY times.
Thread Starter
Teching In
Joined: Dec 2020
Posts: 43
Likes: 1
From: Huntsville, AL
I knew as soon as you posted that it was a Silverado. Forget everything else you're doing and get a scanner on it that can do a crankshaft variation learn. It will most likely fix your problem. It is very common for Silverados to have unexplained misfires with no CEL. I have diagnosed this many, MANY times.
Thread Starter
Teching In
Joined: Dec 2020
Posts: 43
Likes: 1
From: Huntsville, AL
Thread Starter
Teching In
Joined: Dec 2020
Posts: 43
Likes: 1
From: Huntsville, AL
Since I'm going to check the compression soon (waiting on the weather to cooperate), does it make sense to do a leak down test, too? I was thinking since the misfires seem to be random, the leak down test isn't necessary. Probably true for the compression check, too but that should be quick and easy.