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-   -   Ignition Coil Corrosion..and chasing other demons for fun (https://rennlist.com/forums/928-forum/594018-ignition-coil-corrosion-and-chasing-other-demons-for-fun.html)

Speedtoys 10-03-2010 03:13 PM

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. :)

Mrmerlin 10-03-2010 06:56 PM

factory bosch replacement O2 sensor available on Amazon for 63.00

Speedtoys 10-04-2010 01:31 AM

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.

;)

danglerb 10-04-2010 06:05 AM


Originally Posted by Speedtoys (Post 7946098)
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.

Speedtoys 10-04-2010 05:16 PM


Originally Posted by danglerb (Post 7946228)
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.

http://www.speedtoys.com/~gemohler/plugs.jpg

Seven of them looked like the plug on the right.

The rear plug, drivers side, was the plug on the left.

Mrmerlin 10-04-2010 05:56 PM

either leaking injector, bad spark plug wire or low compression for #8 plug

Speedtoys 10-04-2010 06:00 PM


Originally Posted by Mrmerlin (Post 7947786)
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

Hilton 10-04-2010 07:01 PM


Originally Posted by Mrmerlin (Post 7947786)
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.

Speedtoys 10-04-2010 07:08 PM


Originally Posted by Hilton (Post 7948002)
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.

blown 87 10-04-2010 08:42 PM


Originally Posted by Hilton (Post 7948002)
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.

Speedtoys 10-04-2010 11:37 PM

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'.

Landseer 10-04-2010 11:40 PM

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.

Speedtoys 10-04-2010 11:58 PM

Why would it be so much more rich than it was before? Granted...it has lottsa issues to resolve. :)

Hilton 10-05-2010 12:49 AM


Originally Posted by Speedtoys (Post 7948903)
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).

Speedtoys 10-05-2010 12:53 AM


Originally Posted by Hilton (Post 7949017)
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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