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914Bryan
post Apr 13 2013, 01:46 PM
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Howdy, Im going to throw a bunch at you all at once.

I have just started to experience a return to idle problem with my 74 2.0 Djet. It runs ok, but when I stop and the engine returns to idle, it nearly dies. If it does stay running, the idle is surging.

I have experimented with just pushing in the clutch and not downshifting and the engine nearly dies. Even if I downshift to gradually bring down the rpm, once it is in the idle range, it starts surging and nearly dies.

I just reciently installed a new flywheel, clutch and pressure plate and adjusted the valves and did an oil change, but doubt that any of that would be a problem. But as an interesting side note, I did not weigh the new replacement flywheel; I know the one it replaced was a lightened unit. I have now noticed that the motor feels sluggish and does not rev as quickly as it did with the old lightened flywheel.

Do you think that now it is spinning a heaver flywheel it is exposing a problem that a light flywheel covered-up?

Any ideas where to start?
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VaccaRabite
post Apr 13 2013, 02:16 PM
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It feels more sluggish because you have a stock weight flywheel rather then a light one.

The heavier flywheel should make it run smoother, not rougher.

Zach
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914Bryan
post Apr 13 2013, 03:02 PM
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That's what I figured, but thought I would throw it out there anyway. Any ideas on the idling problem though?
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TheCabinetmaker
post Apr 13 2013, 03:55 PM
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Sounds like lean idle. Turn the ecu knob one click clockwise, open throttle and let it snap closed. Repeat till it comes back to idle slowly. If it doesn't help, readjust the tps.
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Bob L.
post Apr 13 2013, 04:44 PM
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Decel valve? (IMG:style_emoticons/default/confused24.gif)
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914Bryan
post Apr 13 2013, 07:51 PM
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QUOTE(The Cabinetmaker @ Apr 13 2013, 02:55 PM) *

Sounds like lean idle. Turn the ecu knob one click clockwise, open throttle and let it snap closed. Repeat till it comes back to idle slowly. If it doesn't help, readjust the tps.


uh, ECU knob? Readjust the TPS?, uh....Sorry, dont know what those parts are or where they are located.. My ignorance is shining right now, can you help me out? (IMG:style_emoticons/default/wacko.gif)
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Dave_Darling
post Apr 13 2013, 11:29 PM
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ECU == Engine Control Unit. On the front side of the battery tray. There's a knob on the D-jet ones after mid-1971 that changes the idle mixture.

TPS == Throttle Position Switch. It's on the throttle body, with a four-wire plug that plugs into it.

Here's your D-jet bible, read it and learn it: http://members.rennlist.com/pbanders . It has pretty much everything that is currently known about the fuel injection system on the 1.7 an 2.0 cars.

--DD
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76-914
post Apr 14 2013, 10:02 AM
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We're not throwing you to the Wolve's Bryan. Dave is right about reading that link. I've re-read and perused that thing 50 times. At first you might be overwhelmed but it falls in place. You'll find that lean idle (or hunting) is a lean condition as Cabinetmaker mentions. If enriching the mixture doesn't help info for testing the TPS is there and quite simple to do with an ohm meter. ALL vacuum hoses must have air tight connections. If in doubt hose clamp it for now. Go to the site and look at all the D Jet components connected to vacuum. You can disconnect and plug all of these components except for the MPS (the one behind the battery with a 4prong conn and 10mm? vac line) and the car will run. If that corrects your idle hunting begin by adding one component at a time until problem returns then you've solved it.
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914Bryan
post Apr 15 2013, 09:25 AM
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OK, I downloaded and printed all the Djet info; lot of reading for sure, thanks Dave. I will keep you updated on my progress on the vaccum line progress. Thanks 76-914.

Cabnet guy, As far as the knob on the ECU, I found it. I may have fiddled with it when I removed it when installing my new firewall insulation kit....This may be my problem. I don't see any reference settings on the knob, but do feel it clicking when I turn it. Just to confirm, click to the right, rich, left, lean?

Does this affect my overall air/fuel mixture settings during regular driving?

Thanks again for all your help,
Bryan
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76-914
post Apr 15 2013, 09:39 AM
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correct. it has 22 positions, IIRC. Start in the middle (11 clicks). no, it only effects the idle circuit.
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TheCabinetmaker
post Apr 15 2013, 10:11 AM
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Pull the rubber cover off the knob.
You'll see a small nib marking the middle.
Start there. Sounds like you got it.
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