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pulled spark plugs - covered in gas?

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i've been having issues (misfire, rough running - totally intermittent) with my 1984 turbo wagon and i think i've tracked down the issue...

 

when i pulled the spark plugs to inspect them #2 and #4 showed normal wear, but #1 seemed to have some fuel on it, and #3 seemed to be mostly saturated in gas. 

 

i did the poor man's stethoscope trick (my ear up to a long-handled screwdriver) against each of the injectors and all seemed to be firing as normal with a consistent pulse, same volume.

 

leaky injectors maybe?

 

is there a way to test the injectors with a multimeter, maybe for resistance? 

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You can measure resistance,but,that merely tells you if the winding is OK not whether they are leaking or sticky

If you have an old style ignition dwell meter,you can use it to compare ECU injector signals between the good and bad ones(they are fired in pairs).

 

Fairly easy to pull the injectors,pressurize the fuel system and check for leaks.I found a leaker on my ea-81t.

 

Be aware that a misfire for any reason(including a too lean mixture) may leave the plugs wet w/fuel.

 

If I suspected injectors,I would swap them to the good side and see if the problem follows.

 

You can have them cleaned and flow tested at a local big rig shop fairly inexpensively.

 

I`d be surprised if the injectors are causing your problem.

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Id say the fuel on the plugs is more indicative of a spark issue.  if its running rich it should still burn but leave a black mess on the plug, raw fuel is more a sign of no spark to ignite it.  

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You can measure resistance,but,that merely tells you if the winding is OK not whether they are leaking or sticky

If you have an old style ignition dwell meter,you can use it to compare ECU injector signals between the good and bad ones(they are fired in pairs).

 

Fairly easy to pull the injectors,pressurize the fuel system and check for leaks.I found a leaker on my ea-81t.

 

Be aware that a misfire for any reason(including a too lean mixture) may leave the plugs wet w/fuel.

 

If I suspected injectors,I would swap them to the good side and see if the problem follows.

 

You can have them cleaned and flow tested at a local big rig shop fairly inexpensively.

 

I`d be surprised if the injectors are causing your problem.

 

that's my next step, pulling that injector and putting it on another cylinder to see if the misfire/richness follows it. 

 

Id say the fuel on the plugs is more indicative of a spark issue.  if its running rich it should still burn but leave a black mess on the plug, raw fuel is more a sign of no spark to ignite it.  

 

my initial thought was a spark issue but resistance across the wire(s) is fine, new coil, new cap and rotor, no play in the disty shaft. what else is there to check? 

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valve addjustment timing and comp test the injectors if leaking you will see a slow drop on preshure gauge if injector is not holding or lift injector out and watch for drips under preshure also check con on coolant temp senser and look for any air intake leaks

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Pull the plug, attach plug wire to plug, ground the plug on the block away from the plug hole, start engine and see if you see a spark.  I have been only getting 14,000 miles on my plugs.  The metal contact inside of the plug wire ends, could also be corroded or broken. 

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i bought a cheap spark tester tool over the weekend, tested all the cylinders for spark and all seem to be strong and consistent. 

 

perhaps it is in fact a leaky injector... i'll bench test the cylinder that's giving me issues and see if that's the issue.

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