 troubleshooting stalling when idling hot, idle/mixture adjustment? |
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| timofly |
 Jul 29 2026, 01:03 PM
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#1
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Member  Group: Members Posts: 175 Joined: 21-February 09 From: VA Member No.: 10,082 Region Association: MidAtlantic Region  |
'74 2.0 with .010 oversize cylinders, original Jetronic fuel injection intact and works great 95% of the time. However, engine idles very slowly (almost off the bottom of the tach scale) and will eventually stall unless throttle is "goosed". Condition only occurs in high ambient temps after 15-20 minutes driving. Then hard to start without a bit of throttle, but starts fine with that little bit of throttle, so I don't think it's fuel vaporization. (Fuel pump has been moved forward and fuel lines are all SS.)
Runs normally otherwise. Cylinder head temp sensor? Idle adjustment? What? Any ideas would be appreciated. Tim |
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| 914werke |
Jul 29 2026, 01:16 PM
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"I got blisters on me fingers" Group: Members Posts: 11,712 Joined: 22-March 03 From: USofA Member No.: 453 Region Association: Pacific Northwest 
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On top of the AFM is a recessed screw to adjust idle mix.
it will have IDK 12 or 14 discernible detent's. Verify where its currently set and increase adjustment as necessary 1 at a time |
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| fiacra |
Jul 29 2026, 01:36 PM
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#3
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Person.Woman.Man.Camera.TV. = MCI Group: Members Posts: 743 Joined: 1-March 19 From: East Bay Region - California Member No.: 22,920 Region Association: Northern California
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QUOTE(914werke @ Jul 29 2026, 12:16 PM)  On top of the AFM is a recessed screw to adjust idle mix. it will have IDK 12 or 14 discernible detent's. Verify where its currently set and increase adjustment as necessary 1 at a time AFM is L-jet. Confusing because the OP says L-Jet, but a '74 2.0 should be D-Jet. Idle speed adjustment on D-Jet is on the throttle body. The knob on the ECU adjusts the idle fuel mixture, and I think that's what may need to be adjusted. |
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| timofly |
Jul 29 2026, 02:14 PM
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#4
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Member Group: Members Posts: 175 Joined: 21-February 09 From: VA Member No.: 10,082 Region Association: MidAtlantic Region |
QUOTE(fiacra @ Jul 29 2026, 03:36 PM) QUOTE(914werke @ Jul 29 2026, 12:16 PM) On top of the AFM is a recessed screw to adjust idle mix. it will have IDK 12 or 14 discernible detent's. Verify where its currently set and increase adjustment as necessary 1 at a time AFM is L-jet. Confusing because the OP says L-Jet, but a '74 2.0 should be D-Jet. Idle speed adjustment on D-Jet is on the throttle body. The knob on the ECU adjusts the idle fuel mixture, and I think that's what may need to be adjusted. My bad, it's a D-Jet. Thanks for the reply, I'll give it a try. |
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Posts in this topic
timofly troubleshooting stalling when idling hot Jul 29 2026, 01:03 PM
timofly
On top of the AFM is a recessed screw to adjust i... Jul 29 2026, 02:13 PM
emerygt350 Is this ljet or djet?
Sounds like your idle mixtu... Jul 29 2026, 01:33 PM emerygt350
Is this ljet or djet?
Sounds like your idle mixt... Jul 29 2026, 01:34 PM timofly
Is this ljet or djet?
Sounds like your idle mix... Jul 29 2026, 02:09 PM timofly
Is this ljet or djet?
Sounds like your idle mixt... Jul 29 2026, 02:07 PM timofly
Is this ljet or djet?
Sounds like your idle mixt... Jul 29 2026, 02:11 PM 914werke Whoops OP used "Jetronic" My mind went t... Jul 29 2026, 02:15 PM emerygt350 If this is new, I might not try to correct it with... Jul 29 2026, 04:26 PM |
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