 ‘74 2.0 Bucking Only When Warmed Up, Runs great when cool |
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| Jackba |
 Sep 14 2019, 04:15 PM
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#1
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Newbie  Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California  |
I originally started this as a “Won’t Start” thread and got a ton of help from the group. Prior to not starting at all I had a problem with bucking at all times, not just when warm.
The process of fixing the no start issue was lengthy and included the following: Ultrasonically cleaned all parts of the distributor and oiled the plates Changed condenser Checked points and gap Checked trigger points Checked power to injectors using a noid light Verified normal spray pattern of injectors Checked CHT resistance Removed fuel tank and cleaned sock Verified hoses were not kinked Replaced fuel filter replaced bad relay board Verified operation of relays Checked fuel pressure. Removed and cleaned FI grounds Checked static timing Cleaned near new TPS Replaced fuel pump Replacing the pump fixed the no start problem. Took the car for a quick drive and all was fine. Decided to install a Pertronix ignition module and change ignition wires at the same time. Car is running a 5 year old Beru blue 3.3 ohm coil. Thinking I had everything solved I took the car out for an extended drive last Sunday. For the first 5 miles it ran absolutely great. Better than ever. Then it started hesitating and the hesitation got worse. It started bucking to a point where I didn’t think I could make it home, but I did. Now I’m wondering what else I can possibly do? Any suggestions would be welcome. Thanks, Jack |
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| Amphicar770 |
Sep 14 2019, 10:32 PM
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#2
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Senior Member Group: Members Posts: 1,219 Joined: 20-April 10 From: PA, USA Member No.: 11,639 Region Association: MidAtlantic Region 
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Similar experience s couple of years ago. Bucking once warm, Died on road twice but once fully cooled would start right up. Turned out to be a loose connector on rear, right side of engine. Once seated properly, problem never recurred. Is your engine wiring harness original?
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| Jackba |
Sep 14 2019, 11:12 PM
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#3
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Newbie Group: Members Posts: 40 Joined: 13-July 18 From: Sacramento Member No.: 22,308 Region Association: Northern California |
QUOTE(Amphicar770 @ Sep 14 2019, 11:32 PM)  Similar experience s couple of years ago. Bucking once warm, Died on road twice but once fully cooled would start right up. Turned out to be a loose connector on rear, right side of engine. Once seated properly, problem never recurred. Is your engine wiring harness original? Thanks for responding. My FI harness was rebuilt by Jeff Bowlsby a few years ago. Not many hours on it. Are you referring to the 3 FI ground wires on the top rear of the engine case or another location? |
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Posts in this topic
Jackba ‘74 2.0 Bucking Only When Warmed Up Sep 14 2019, 04:15 PM
Amphicar770
Similar experience s couple of years ago. Buckin... Sep 16 2019, 06:13 PM rjames The only time my car ever experienced bucking was ... Sep 15 2019, 10:02 AM Jackba
The only time my car ever experienced bucking was... Sep 15 2019, 01:42 PM porschetub
The only time my car ever experienced bucking wa... Sep 15 2019, 02:36 PM Jackba
[quote name='Jackba' post='2747378' date='Sep 16 ... Sep 15 2019, 04:13 PM |
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