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Knock sensor question

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Old 09-13-2017, 03:14 PM
  #21  
aklim
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Originally Posted by luvmy88 View Post
Thought it was clogged fuel injectors so had the cleaned (flush)

Does the ECM have to learn the new coil?

Bad ground on the coil?

Bad ignition module?

All of the above? None of the above? Or could all of this just be bad wires?
What injectors do you have? Take a peek and see if they are Multecs. Your flush could hurt the already worthless and fragile things.

You need to change the wires and clear the codes with the scanner so we can start with a fresh slate. Till then we can guess.

The ECM is pretty primitive and doesn't care about the coil as long as it works.

Someone will have to get back to you. I tossed my old coil with the motor so I have little to no experience with the big cap coil.

Maybe. While you are waiting, I suggest you take the cap and rotor off and see if there are boogers hanging off the terminal. If so, replace. While it is off, check the ignition module by having a parts shop test it.

Until we have the new wires installed correctly and the engine timing checked, we won't know.
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Old 09-17-2017, 07:33 AM
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Default While I wait for new plug wires

I pulled the spark plugs to check condition. Several plugs look carboned up and oily... I will replace. While I had them pulled I figured I would do a compression test as I've never done on this car.
All plugs removed, fuel rail fuse removed, peddle to the floor and cranked 5 times. This was a dry test and all cylinders checked between 152 and 160. I think that's OK for an almost 30 year old engine???
But I noticed the electric fan kicks on, IS THAT NORMAL??? The engine is cold.
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Old 09-17-2017, 08:33 AM
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Could be but I'd worry about the plugs first. Probably have to change the valve stem seals
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Old 09-17-2017, 01:56 PM
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Originally Posted by aklim View Post
Could be but I'd worry about the plugs first. Probably have to change the valve stem seals
I had the Ignition module checked good, also Cap and Rotor look good.
Still waiting on plug wires, expecting delivery Tues.
I wish I knew more about using a multimeter for testing.
By the way, the fuel injectors look like the Bosch, but they are not all identical. Two look exactly like in your pic and the other six look similar but have a green ring around then. They have never been replaced as long as I've owned the car (23 yrs)
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Old 09-17-2017, 05:29 PM
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Originally Posted by luvmy88 View Post
I had the Ignition module checked good, also Cap and Rotor look good.

Still waiting on plug wires, expecting delivery Tues.

I wish I knew more about using a multimeter for testing.

By the way, the fuel injectors look like the Bosch, but they are not all identical. Two look exactly like in your pic and the other six look similar but have a green ring around then. They have never been replaced as long as I've owned the car (23 yrs)
If you sent it to an Autozone or something, that should suffice. Cap and rotor you need to see if there are boogers hanging off the terminal or they are loose.

Till then I'm not sure what we can do since they are a known bad.

A scanner, if you want to maintain it, is a must.

That could be an issue whether you feel it or not. The ECM can compensate so that you don't really know so the old school "feel technique" isn't as good as it once was. I suspect the injectors went bad and under warranty or "el cheapo payment", 6 were replaced instead of all 8. I would dump all 8 and get a reman set HERE.
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Old 09-22-2017, 01:03 PM
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Installed brand new MSD super conductor wires and new plugs and got the same light show, with wires arcing multiple places.
When I initially started it was hard to keep running, had to nurse it with gas. SES light came on then went out and then it idled fine from then on. Let it idle until it got hot enough for fan to turn on.
One thing... the fan came on at initial start, engine cold???
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Old 09-22-2017, 04:14 PM
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Originally Posted by luvmy88 View Post
Installed brand new MSD super conductor wires and new plugs and got the same light show, with wires arcing multiple places.
When I initially started it was hard to keep running, had to nurse it with gas. SES light came on then went out and then it idled fine from then on. Let it idle until it got hot enough for fan to turn on.
One thing... the fan came on at initial start, engine cold???
On the wires or at the cap?
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Old 09-24-2017, 07:37 AM
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Originally Posted by aklim View Post
On the wires or at the cap?
The spark jump is at the wires, multiple places on both sides, just like before.
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