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Misfire Just Started Randomly? Any Ideas?


puggy

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I was driving home this morning from work (only a few miles drive), halfway home the engine suddenly dropped in power and a stuttering noise started. I stopped the car and it sounds like a misfire at idle and when it’s running. It’s a really hard noise to describe but it sounds rough almost like a gargling noise. I switched the engine off then back on and it made no difference. No warning lights or other indicators that there is a problem.

 

This afternoon I started it back up from cold and it ran fine. As soon as the engine began to rise in temperature, the misfire noise returned. When applying the throttle, it’s more prominent.

 

Firstly, it’s a 93’ NA auto. I’m aware that there is a leak at the rocker cover gasket and new seals are on order. A friend has suggested that this leak could have caused the spark plugs to flood. They will get changed. I’m really not very technically minded and a lot of things I read on the forum from those who have had similar issues completely confuses me. I’m also aware that there could be many reasons that cause the engine to misfire.

 

Anyone had similar and any suggestions? I’ve only owned the car a few months and up until now it has run as it should. I have no service history to tell me when the plugs or any other components were replaced.

 

Any advice would be appreciated. Thanks.

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Ok, look at the distributor at the front left of the engine, it has 7 wires/cables coming from it, one to the inner wing area the other 6 to the spark plugs.

 

Remove the grey plastic engine covers front and rear using an Allen key (I'd leave these off until the cam covers are done) then you'll see the cables running down the valley between the two cam covers.

A firm grip on the plastic/rubber tops these cables go to, then wiggle/pull up and out. If you can get to the rear most one that's the one often most covered in oil. If the bottoms are covered in oil you know there is aa fair bit of oil down there, you may be able to remove the metal strip that has the holes in for the plugs (I can't remember if you can do this without removing anything else) to get a better look. If you can see oil down the wells (they are quite deep) then use kitchen towel etc to soak it up, bare in mind there is no drain here so don't go in with fluids/degreaser etc.

 

You'll need to clean it all up for the cam cover and spark plug changes anyway and after it may well cure the misfire for a while...

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Ok, look at the distributor at the front left of the engine, it has 7 wires/cables coming from it, one to the inner wing area the other 6 to the spark plugs.

 

Remove the grey plastic engine covers front and rear using an Allen key (I'd leave these off until the cam covers are done) then you'll see the cables running down the valley between the two cam covers.

A firm grip on the plastic/rubber tops these cables go to, then wiggle/pull up and out. If you can get to the rear most one that's the one often most covered in oil. If the bottoms are covered in oil you know there is aa fair bit of oil down there, you may be able to remove the metal strip that has the holes in for the plugs (I can't remember if you can do this without removing anything else) to get a better look. If you can see oil down the wells (they are quite deep) then use kitchen towel etc to soak it up, bare in mind there is no drain here so don't go in with fluids/degreaser etc.

 

You'll need to clean it all up for the cam cover and spark plug changes anyway and after it may well cure the misfire for a while...

 

Perfect, start with the sparks being changed first then and go from there. Thanks.

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