 Engine Stuttering |
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| GulfRacer |
 Sep 20 2025, 01:48 PM
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#1
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Newbie  Group: Members Posts: 8 Joined: 19-April 25 From: NJ Member No.: 28,724 Region Association: North East States  |
I'm hoping some collective wisdom can help me through a frustrating problem. I have 1974 Bumblebee that I've owned for about 6 months. The 2.0 was rebuilt to a 2056 shortly before I purchased it. It has a Raby 9590 camshaft, original D-Jet and 123 distributor. When I first got the car, it was running great. It has since developed an intermittent stutter/bucking. It occurs most commonly around 3000 RPM when cruising, but once it happens, it continues when applying throttle. It doesn't usually occur until the engine has warmed up - the first several minutes of the drive are usually good.
I replaced the throttle sensor board which did not solve the problem. I disconnected the throttle sensor, and the problem is still present. I replaced the fuel injection harnesss which did not help. The fuel injectors are all new with the engine rebuild, but cylinder 3 injector stopped firing a few months ago, and I replaced it with a new one. I'm at a loss as to where to go next. Any advice would be greatly appreciated. Jason |
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| emerygt350 |
Nov 2 2025, 11:32 AM
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Advanced Member Group: Members Posts: 3,364 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
I wonder if this could be one of those rare times the ECU is going? Do you have an extra?
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| GulfRacer |
Nov 2 2025, 11:37 AM
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#3
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Newbie Group: Members Posts: 8 Joined: 19-April 25 From: NJ Member No.: 28,724 Region Association: North East States |
QUOTE(emerygt350 @ Nov 2 2025, 12:32 PM)  I wonder if this could be one of those rare times the ECU is going? Do you have an extra? That's my thought, either the ECU or a fault in the 123 distributor trigger mechanism. Unfortunately, I don't have an extra to test. |
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Posts in this topic
GulfRacer Engine Stuttering Sep 20 2025, 01:48 PM
Dave_Darling Wiggle all of the wiring in the engine bay while t... Sep 20 2025, 03:07 PM emerygt350 Interesting. That is a spot where a lean miss is ... Sep 20 2025, 04:06 PM Olympic 914 I was having a similar problem
On mine it was an ... Sep 20 2025, 05:21 PM Lockwodo Would a faulty MPS cause the lean condition and mi... Sep 20 2025, 06:55 PM
emerygt350
Would a faulty MPS cause the lean condition and m... Sep 21 2025, 07:47 AM emerygt350
Would a faulty MPS cause the lean condition and ... Sep 21 2025, 07:48 AM GulfRacer
[quote name='emerygt350' post='3225097' date='Sep... Sep 21 2025, 11:37 AM cgnj I'm thinking ignition coil. Sits on the tin ab... Sep 23 2025, 12:15 AM Lockwodo Or perhaps a dodgy ground connection? Sep 23 2025, 09:59 AM JP101 Thanks for additional suggestions. Coil may make s... Sep 23 2025, 08:22 PM GulfRacer I still haven't sorted this problem out, and s... Nov 1 2025, 12:08 PM Ishley Do you have a Bluetooth 123+? If you do you can c... Nov 1 2025, 03:18 PM emerygt350 I would try replacing the coil and verify it is wi... Nov 2 2025, 06:52 AM GulfRacer I have some additional information. Thank you for... Nov 2 2025, 10:58 AM Lockwodo It does seem like the trigger point pulse from the... Nov 2 2025, 11:20 AM GulfRacer
It does seem like the trigger point pulse from th... Nov 2 2025, 11:23 AM emerygt350
I wonder if this could be one of those rare time... Nov 2 2025, 07:42 PM Ishley I’m wondering if you should check the spray patt... Nov 2 2025, 02:45 PM GulfRacer
I’m wondering if you should check the spray pat... Nov 2 2025, 04:24 PM |
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