 Timing help |
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| r_towle |
 Dec 19 2005, 01:15 PM
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#1
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Custom Member  Group: Members Posts: 24,570 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States 
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Ok,
stock 1.8 liter ljet. The book says timing is 7.5 BDTC at 900 rpms... I cant get there... I can get close, but the engine dies if I set it right on. The dwell is perfect, the vacuum lines are all new. It just wants to die if I get it close...so right now I am advanced a bit , it idles perfect and revs fine (have yet to drive it to see if it detonates...) I messed with the idle screw while doing it to keep it running... I need help trying to diagnos why it will not allow me to time it correctly...yes the single vacuum line was disconnected from the dizzy and plugged. there are two connections at the dizzy, but only one on the throttle body, one is for advance and one for retard...the retard is not hooked up, no place to plug it in..I know that is the way they came... Rich |
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| Mueller |
Dec 19 2005, 01:43 PM
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#2
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914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None
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is the o-ring on the oil filler cap in good condition?? L-jet does not like vac leaks..... |
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| r_towle |
Dec 19 2005, 01:47 PM
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#3
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Custom Member Group: Members Posts: 24,570 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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hell if I know...Il go look...
That would make it run faster though..would it not... On my djet, a vacuum leak makes it rev more... Rich |
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| Dave_Darling |
Dec 19 2005, 04:01 PM
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#4
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914 Idiot Group: Members Posts: 14,981 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California
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Djet != Ljet.
D-jet systems will tend to idle high when there are vacuum leaks. L-jet systems will tend to idle "funny" or "really badly" (or not at all!) when there are vacuum leaks. --DD |
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| lapuwali |
Dec 19 2005, 04:09 PM
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#5
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743  |
On D-Jet, a big vacuum leak is simply bypassing the throttle, so it's like having the throttle partway open or the AAR open. The ECU "sees" that extra air in the manifold pressure, so the fuelling is correct. On L-Jet, a leak downstream of the AFM means unmeasured air is getting in, so the mixture goes lean. With a small leak, the problem will only show up at low revs, since the air coming in through the extra hole falls as a percentage of total flow as the revs rise.
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| r_towle |
Dec 20 2005, 09:59 AM
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#6
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Custom Member Group: Members Posts: 24,570 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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so, if I suspect the Aux Air valve...how would I go about testing it...
Rich |
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| Joe Ricard |
Dec 20 2005, 10:10 AM
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#7
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CUMONIWANNARACEU Group: Members Posts: 6,811 Joined: 5-January 03 From: Gautier, MS Member No.: 92 |
Stick a chop stick in there. if it goes through when the car is warm that is bad.
Chopsticks may be substituded for anything that won't break or get stuck. OK really engine cold the valve should be opened. as the engine warms the valve will close no air flow. this can be checked with engine running and hose pulled off the AAR valve. |
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| r_towle |
Dec 20 2005, 10:26 AM
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#8
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Custom Member Group: Members Posts: 24,570 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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so for testing, I can just unplug it, and close up the intake and AAR valve like my Djet has....
It looked like a newer valve on the ljet...looks more modern...but I will close it off and see if I can get the timing right while chasing the lovely vaccuum leaks... Rich |
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