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> Can somebody ID this new idle quirk?, starts & runs well -- until warm
Prospectfarms
post May 31 2011, 10:43 PM
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O.K., I'm better now... D-jet is driving me to drink.

The 1.7 starts and runs well until it warms up. After 10 min. idling smoothly @ 900 it hesitates two or three times and stops idling at all, which means I can't keep it running long enough to set the timing. I can keep it going by feathering the throttle, but my nice smooth idle is gone. I reproduced the symptom three times in a row today.

By clamping off the Vac hoses one-by-one it appears the FI components seem to be doing what they're supposed to. No other vacuum or capacitance probs. found so far. Haven't checked the injectors.

This started after I repaired the ground strap on my distributor -- must have bumped something else. CHT?

I have the FI diagnostic checklists and am working on them. If this was a carburetor I'd say it was running with a clogged idle jet (IMG:style_emoticons/default/wacko.gif) . These symptoms seem specific and uncommon. At least I've not seen others posts that describe the same thing. Did I miss one?
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ThinAir
post Jun 1 2011, 10:56 PM
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Even though this problem started after a specific repair... when was the last time you adjusted your valves? Generally with D-Jet systems you want to start with basic, simple (and free) things first. Vacuum for the rest of the system is affected by proper valve adjustment so if your valves aren't right you'll chase your tail on a bunch of other stuff because the foundation isn't solid. Besides that, I've personally experienced that valves which are too tight will run great when cold, but produce a crappy running and stalling engine once they warm up and close up the gap.
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Prospectfarms   Can somebody ID this new idle quirk?   May 31 2011, 10:43 PM
kg6dxn   Try this... L Jet Manual   May 31 2011, 10:52 PM
Prospectfarms   Try this... L Jet Manual Thnkz Mike, Although...   Jun 1 2011, 06:16 AM
SirAndy   CHT? Could be. I have seen this exact behavior wh...   May 31 2011, 10:54 PM
Prospectfarms   CHT? Could be. I have seen this exact behavior w...   Jun 1 2011, 06:46 AM
vsg914   The cold start valve does not come on till the air...   Jun 1 2011, 07:17 AM
Prospectfarms   The cold start valve does not come on till the ai...   Jun 1 2011, 07:46 AM
Bartlett 914   The cold start valve does not come on till the ai...   Jun 1 2011, 07:47 AM
Prospectfarms   The cold start valve does not come on till the a...   Jun 1 2011, 07:50 AM
underthetire   Yep, i'll bet AAR myself. Should idle about 15...   Jun 1 2011, 08:33 AM
vsg914   Unplug the hose to the AAR at the air cleaner and ...   Jun 1 2011, 08:38 AM
Tom   From above; Great info! thanks. Assumed inc...   Jun 1 2011, 01:53 PM
Prospectfarms   From above; The ECU adjusts fuel mixture b...   Jun 1 2011, 10:43 PM
Bartlett 914   I think the idle screw is at the end of its t...   Jun 2 2011, 07:56 AM
charliew   Tom, is it really Magala Red?   Jun 1 2011, 04:28 PM
ThinAir   Even though this problem started after a specific ...   Jun 1 2011, 10:56 PM
Prospectfarms   Generally with D-Jet systems you want to start wi...   Jun 2 2011, 04:48 AM
Tom   The information I have is Paul Anders' stuff a...   Jun 2 2011, 10:42 AM
Prospectfarms   The information I have is Paul Anders' stuff ...   Jun 2 2011, 11:15 AM
r_towle   Unplug and cap all vacuum lines at the plenum. the...   Jun 2 2011, 11:13 AM
Prospectfarms   Unplug and cap all vacuum lines at the plenum. th...   Jun 2 2011, 11:28 AM
r_towle   Unplug and cap all vacuum lines at the plenum. t...   Jun 2 2011, 11:44 AM
r_towle   look in the classics forum here for Cap'n crus...   Jun 2 2011, 11:17 AM
Prospectfarms   look in the classics forum here for Cap'n cru...   Jun 7 2011, 08:36 PM
Prospectfarms   PS: Ill go through those procedures, set valve cle...   Jun 2 2011, 11:34 AM
benalishhero   Open loop in modern EFI systems refers to the engi...   Jun 2 2011, 05:55 PM
Prospectfarms   Thanks benalishhero, So the word "open" ...   Jun 2 2011, 06:42 PM
Prospectfarms   Unplug and cap all vacuum lines at the plenum. th...   Jun 4 2011, 09:46 PM
Prospectfarms   Follow up and diagnosis. Ultimately it was the fue...   Jun 15 2011, 10:08 PM
ThinAir   Besides, starting with the basics, the other thing...   Jun 4 2011, 11:04 PM
Prospectfarms   It's sounding a bit to me like a solder point...   Jun 5 2011, 06:13 AM
Prospectfarms   Update: Pulled ECU and tested resistance of CHT ...   Jun 5 2011, 12:00 PM
Prospectfarms   Update: Here's what I am presently dealing ...   Jun 5 2011, 10:03 PM
Prospectfarms   ThinAir, did you do more work on your son's 91...   Jun 7 2011, 08:06 AM
Tom   You should measure the value of the CHT when it is...   Jun 6 2011, 07:18 AM
Prospectfarms   You should measure the value of the CHT when it i...   Jun 6 2011, 08:03 AM
Prospectfarms   You should measure the value of the CHT when it ...   Jun 6 2011, 09:59 AM
Tom   I have heard of cracked plenums causing a vacuum l...   Jun 6 2011, 12:08 PM
Prospectfarms   I have heard of cracked plenums causing a vacuum ...   Jun 6 2011, 12:55 PM
ThinAir   This actually all started with this: http://www.91...   Jun 7 2011, 03:36 PM
Prospectfarms   This actually all started with this: http://www.9...   Jun 7 2011, 08:22 PM
speed metal army   give us the part # of that pump! :)   Jun 15 2011, 10:23 PM
Prospectfarms   give us the part # of that pump! :) Began ...   Jun 15 2011, 10:36 PM
ThinAir   Congratulations on figuring it out! Persistenc...   Jun 16 2011, 12:47 AM


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