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j91z28d1

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a valve spring is definitely worth checking for.

you can also try mechanically release the stuck lifter. it seems to work if it hasn't been driving long enough with a stuck lifter that it damaged the cam or the lifter holders
 
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Nutro

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So, I was going to ask. Should I check compression first you think or pull valve cover and check/watch valve spring/rocker? Not being a smart alec, genuinely asking.
 

OR VietVet

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When you are cranking the engine over for a compression, you will get a little oil squirting if valve cover is off but if the valve cover is off, you may be able to see right away what is wrong. It's a choice because if you have low compression, you are gonna pull the valve cover asap anyway.
 

Grady_Wilson

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I would start with a compression test and go from there.
If you have low to none on that cylinder then you'll be pulling the valve cover to check the valve train, anyway.
 
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Nutro

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Ok so dumb question. I'm going to attempt the compression test today and remove valve cover. Question: When I do the compression test, do I disconnect both sides of the coil packs and just crank it up. Same question applies to removing valve cover to watch rocker arm. Do I disconnect both coil packs and just crank or can I disconnect the pass side only?
 

OR VietVet

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Leave the valve cover on when doing the compression test. Remove the fuel pump relay at the relay box. You do not want it to start while doing the test. Just remove the plug wire and remove plug. You said cylinder #4 is the problem hole. Remove #2 and #6 plugs too. If you do not know the cranking process for the testing, look at, at least 3-4 you tube videos for help. The first one you see may be wrong. Note the reading and then do the cylinders on each side for comparison sake. If the reading is low er than the other two cylinders, then you can dig deeper and remove valve cover and watch while doing the test again. If you can take a video or pics and post here, so much the better. IIRC a good compression reading is about 170 psi. If you get close to that, great, but you want the other two to read close to the good reading, too. If you have never done a compression test, make sure you also know what line to thread in the hole for the test.
 
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Nutro

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Thank you! I'll watch a few videos. The last time I did a compression test was on an old SBC like 20 years ago and I just don't remember much about it
 
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Nutro

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I've already hit my first head scratcher. How am I missing the fuel pump relay but the vehicle fires up fine?
 

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