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Discussion Starter #1
So i did my vvti seal, and valve cover gaskets and decided to add new spark plugs and wires along with the job

i noticed the Coil on connecters fell apart when i pulled them out and one ignition coil was pulling out a little easy but i put everything in and tried to connect the connectors back (which i already order new connectors) but the car ran fine at first then when i came back, the car started to shake in drive and the engine started to knock around cylinder 6 location
What are possible diagnostics before i take it to the shop
 

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You need to double check those injector harness clips. I bet one shook loose. At their age now they almost always fall apart. Unfortunately that means pulling the y part of the intake manifold back off to inspect. You may be able to zip tie the connector back into place in a pinch.
 

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Discussion Starter #3
You need to double check those injector harness clips. I bet one shook loose. At their age now they almost always fall apart. Unfortunately that means pulling the y part of the intake manifold back off to inspect. You may be able to zip tie the connector back into place in a pinch.
So they could have disconnected when pulling the manifold up? You sure it isn't the coil pack connectors. This is a fuel problem?
 

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Discussion Starter #4
You need to double check those injector harness clips. I bet one shook loose. At their age now they almost always fall apart. Unfortunately that means pulling the y part of the intake manifold back off to inspect. You may be able to zip tie the connector back into place in a pinch.
I checked and the clips are in. None of them are loose.
 

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Discussion Starter #5
Maybe a spark plug came loose? But i also dk if pre-ignition would cause engine knocking
 

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I checked and the clips are in. None of them are loose.
No the connectors wouldn’t come loose when taking off the intake manifold. I was saying that in order to double check the connectors on the coil packs, you would need to remove the “Y” piece on the intake manifold to inspect them.

I assume that you are talking about the 3 wiring harness connectors that plug into the coil packs correct? Those are the connectors that broke? Mine did, they usually do at this age. If they come loose then you will get misfires.

If you have a check engine light on now, scan for codes and let us know what you get.

since you did not touch the injectors at all, there shouldn’t be a problem with those UNLESS one did fail by coincidence.
 

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Maybe a spark plug came loose? But i also dk if pre-ignition would cause engine knocking
Shouldn’t be a problem with pre-ignition on an otherwise stock engine and with only basic maintenance being completed on it. A spark plug could have came loose if you didn’t tighten them down properly. Should be torqued down to ~13 ft lbs.

I believe NGK says 1/2 turn after the washer has hit the seat.
 

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Discussion Starter #8
Shouldn’t be a problem with pre-ignition on an otherwise stock engine and with only basic maintenance being completed on it. A spark plug could have came loose if you didn’t tighten them down properly. Should be torqued down to ~13 ft lbs.

I believe NGK says 1/2 turn after the washer has hit the seat.
Ok thank you my new clips come in monday, so i’ll go back in with a buddy’s torque wrench and torque the them properly and put the new clips on. One last question
A loose connector on a coil pack would cause engine/piston knock. Im still learning on diagnosing problems.
 

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Discussion Starter #9
Shouldn’t be a problem with pre-ignition on an otherwise stock engine and with only basic maintenance being completed on it. A spark plug could have came loose if you didn’t tighten them down properly. Should be torqued down to ~13 ft lbs.

I believe NGK says 1/2 turn after the washer has hit the seat.
Ok thank you my new clips come in monday, so i’ll go back in with a buddy’s torque wrench and torque the them properly and put the new clips on. One last question
A loose connector on a coil pack would cause engine/piston knock. Im still learning on diagnosing problems.
 

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Ok thank you my new clips come in monday, so i’ll go back in with a buddy’s torque wrench and torque the them properly and put the new clips on. One last question
A loose connector on a coil pack would cause engine/piston knock. Im still learning on diagnosing problems.
I loose wiring harness connector on a coil pack will cause a misfire. It won’t cause a metallic “knock” sound.

it will cause the engine to shake some at idle. It will cause a loss of power. If you have a CEL then scan for the code.
 

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Discussion Starter #11
I loose wiring harness connector on a coil pack will cause a misfire. It won’t cause a metallic “knock” sound.

it will cause the engine to shake some at idle. It will cause a loss of power. If you have a CEL then scan for the code.
Heres a video of the noise

Some buddy’s say a spark plug may have gotten loose
 

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Question:

1. you have a check engine light on?


From the video, it sounds like it is running just fine (as far as misfires are concerned)

2. Was the engine at normal operating temperature?

If it was, it sounded like you had a vacuum leak because the idle seems high.

I do hear slight knocking while it is being revved up.

Did you ever pull it back apart and double check everything like you said you were going to do on Monday?
 

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Discussion Starter #13 (Edited)
Question:

1. you have a check engine light on?


From the video, it sounds like it is running just fine (as far as misfires are concerned)

2. Was the engine at normal operating temperature?

If it was, it sounded like you had a vacuum leak because the idle seems high.

I do hear slight knocking while it is being revved up.

Did you ever pull it back apart and double check everything like you said you were going to do on Monday?
so i ordered a new radiator because ive been having alot of backpressure on my radiator and seeing coolant all under my hood and it leaks out so im running on either low or no coolant currently so the engine heat meter is either half or a lil more than that. Also i shouldn't have a vacuum leak i placed all hose and only one cracked but i replaced it with a tighter clamp for now

I currently have no time so im sendingit to a mechanic just hoping i dont have bad internal damage
Also that was cold start in the video

- Could a possibility also be improper torque on my spark plugs cause its sounds like engine knock it was louder the other day but quieter today
 

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Ok. So there seems to be a lot of other issues going on.

Probably not a vacuum leak. Just sounded like one. It was a cold start so idle would have been higher than normal anyway.

There was some light knocking I heard. Wasn’t aware of the cooling issue. Hopefully you got that sorted out. You should have changed out the thermostat at the very least when doing the radiator. It could be stuck shut.
 

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Discussion Starter #15
Ok. So there seems to be a lot of other issues going on.

Probably not a vacuum leak. Just sounded like one. It was a cold start so idle would have been higher than normal anyway.

There was some light knocking I heard. Wasn’t aware of the cooling issue. Hopefully you got that sorted out. You should have changed out the thermostat at the very least when doing the radiator. It could be stuck shut.
So it was a loose injector lol wow
 
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