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Ignition Coil Corrosion..and chasing other demons for fun

Old 10-03-2010, 03:13 PM
  #31  
Speedtoys
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First peeks..

Vac line was completely off the rear fuel damper
Flappy port vac line, was broken 6" from the solenoid
Cant hold vac behind the dash *duh*
Front knock sensor wire to the sensor from the plug is _hammered_
The A/C compressor just threw it belt on a test start (idles better with the damper plugged in)
AFM ya..able to pull right out, and have adjusted cable to just hear the off-idle TPS click now.

Well..now I know what im saving up parts for now.

Last edited by Speedtoys; 10-03-2010 at 09:19 PM.
Old 10-03-2010, 06:56 PM
  #32  
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factory bosch replacement O2 sensor available on Amazon for 63.00
Old 10-04-2010, 01:31 AM
  #33  
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Went to peek at the hatch release..why doesnt it work..well, there IS no hatch release motor in the mount in the back. Yup, there's the problem.

Old 10-04-2010, 06:05 AM
  #34  
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Originally Posted by Speedtoys
Went to peek at the hatch release..why doesnt it work..well, there IS no hatch release motor in the mount in the back. Yup, there's the problem.

Don't worry too much, they usually don't work any better with a motor.
Old 10-04-2010, 05:16 PM
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Originally Posted by danglerb
Don't worry too much, they usually don't work any better with a motor.
Ya..I read a thread about that.

However, these were the plugs I pulled out.



Seven of them looked like the plug on the right.

The rear plug, drivers side, was the plug on the left.
Old 10-04-2010, 05:56 PM
  #36  
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either leaking injector, bad spark plug wire or low compression for #8 plug
Old 10-04-2010, 06:00 PM
  #37  
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Originally Posted by Mrmerlin
either leaking injector, bad spark plug wire or low compression for #8 plug

Ko..probly wont get into those diagnosis..until the top end tear down this Nov/Dev/Jan.


I dont have -a- spare plug wire to test with, dunno if I have a comp tester...or a spare injector...and dont wanna disturb the fuel rail of unknown age/condition until its time
Old 10-04-2010, 07:01 PM
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Originally Posted by Mrmerlin
either leaking injector, bad spark plug wire or low compression for #8 plug
Or possibly a poor spark plug? (wrong gap etc.)

Replace those fancy things with some Bosch WR7DC copper single-electrode ones, correctly gapped (memory says 0.86mm, but check the owners manual for correct spec). Plenty of reports here of curing ignition stumbles by reverting to the factory-recommended plugs.
Old 10-04-2010, 07:08 PM
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Originally Posted by Hilton
Or possibly a poor spark plug? (wrong gap etc.)

Replace those fancy things with some Bosch WR7DC copper single-electrode ones, correctly gapped (memory says 0.86mm, but check the owners manual for correct spec). Plenty of reports here of curing ignition stumbles by reverting to the factory-recommended plugs.
Yup, proper plugs are in there, gapped to .7mm, +/- .1 by spec. But they all fit my .71mm wire tightly.

Might just pull the back two on that side, and re-assess.
Old 10-04-2010, 08:42 PM
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Originally Posted by Hilton
Or possibly a poor spark plug? (wrong gap etc.)

Replace those fancy things with some Bosch WR7DC copper single-electrode ones, correctly gapped (memory says 0.86mm, but check the owners manual for correct spec). Plenty of reports here of curing ignition stumbles by reverting to the factory-recommended plugs.
Yep.
Old 10-04-2010, 11:37 PM
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So..I sealed out the vac leak that the flappy valve had been, put the fuel damper vac hose back -on- that was off, and the result was threefold.

1) Runs MUCH better, but still not right.
2) Tranny shifts as it should, perfect.
3) Runs rich as heeeell. I have a brown bumper above the exhaust now.


Wasnt -that- bad with all the leaks.


Granted, I still have leaks..for sure...just much less of a 'leak'.
Old 10-04-2010, 11:40 PM
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Vac hose is for safety if internals of dampner leak -- leaked fuel then gets sucked into manifold.

So any runnability improvement would be from reducing the vac leak from the open ended hose.
Old 10-04-2010, 11:58 PM
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Why would it be so much more rich than it was before? Granted...it has lottsa issues to resolve.
Old 10-05-2010, 12:49 AM
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Originally Posted by Speedtoys
Why would it be so much more rich than it was before? Granted...it has lottsa issues to resolve.
Likely now running rich as a result of the LH adaption routines having previously compensated for the unmetered air leak(s).

The O2 sensor input would have caused the LH brain to increase fuelling until the detected mixture was correct rather than lean.. and those memory tables are persistent between starts of the car, as they're stored in flash.

Disconnect the battery for a min to wipe the flash memory in the LH, and then reconnect. It'll take 10 mins or so of driving for the LH to re-adapt the idle speed and idle mixture to correct parameters based on inputs, after which it should be more normal (idle will hunt up and down during the adaption routine).
Old 10-05-2010, 12:53 AM
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Originally Posted by Hilton
Likely now running rich as a result of the LH adaption routines having previously compensated for the unmetered air leak(s).

The O2 sensor input would have caused the LH brain to increase fuelling until the detected mixture was correct rather than lean.. and those memory tables are persistent between starts of the car, as they're stored in flash.

Disconnect the battery for a min to wipe the flash memory in the LH, and then reconnect. It'll take 10 mins or so of driving for the LH to re-adapt the idle speed and idle mixture to correct parameters based on inputs, after which it should be more normal (idle will hunt up and down during the adaption routine).

I considered that, and pulled the wing-nut ground strap under the tool tray for 2min this AM before leaving for work.

I was Mr Brown Bumper today from the richness.


PS: The car idled just fine after I reconnected...maybe I should go pull that for the night...


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