 2500 RPM stumble partial throttle 2.0 -4 |
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| SVG223 |
 Mar 13 2025, 08:35 PM
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#1
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Member  Group: Members Posts: 113 Joined: 6-February 22 From: Benton Arkansas Member No.: 26,317 Region Association: None  |
2400-2600 rpm stumble with partial throttle, stumble goes away under full throttle. Runs smooth at all other RPMs. Pulled the plugs, a little lean maybe?
Edit 3-17-25 I found a possible cause; worn distributor bushings causing a variation in the points gap. |
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Replies
| brant |
Mar 15 2025, 10:06 AM
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#2
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914 Wizard Group: Members Posts: 11,952 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains 
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Agree with Superhawk.
All of the basics first Timing valves dwell? And plugs. Fuel pressure to stock. Check the cht (that is what they put the resistor on…. Not the MPs). I would not recommend a rheostat. As it changes the mixture across all rpm. Where as a MPS tune adjust for engine load and not at all rpm. I wouldn’t ever even try to mess with an MPS unless you have an AFR installed on the car |
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Posts in this topic
SVG223 2500 RPM stumble partial throttle 2.0 -4 Mar 13 2025, 08:35 PM
jim_hoyland TPS ? Common issue…. Mar 13 2025, 08:40 PM
dr914@autoatlanta.com as a stab in the dark, I agree, and check the grou... Mar 15 2025, 11:02 AM gonzo54 2.0 DJET? I would suspect TPS board - there are ma... Mar 13 2025, 08:49 PM SVG223 That sounds reasonable. I replaced the TPS board 3... Mar 13 2025, 09:03 PM emerygt350 That is looking very lean as well. Is this stock?... Mar 14 2025, 06:40 AM SVG223
That is looking very lean as well. Is this stock... Mar 14 2025, 05:23 PM Superhawk996
I had these plugs under a strong LED shop light ... Mar 15 2025, 07:07 AM SVG223
I had these plugs under a strong LED shop light... Mar 15 2025, 01:26 PM Superhawk996 None at of those plugs are lean Mar 14 2025, 08:05 AM emerygt350
None at of those plugs are lean
Maybe I don... Mar 14 2025, 10:00 AM Superhawk996
None at of those plugs are lean
Maybe I don... Mar 14 2025, 11:46 AM emerygt350
[quote name='emerygt350' post='3196271' date='Mar... Mar 14 2025, 12:02 PM windforfun Try some electronic contact cleaner on the TPS. T... Mar 14 2025, 11:44 AM SVG223
Try some electronic contact cleaner on the TPS. ... Mar 14 2025, 07:44 PM Superhawk996 Here’s your post ?
http://www.914world.com/bbs2/... Mar 14 2025, 12:31 PM emerygt350 To me that is a clean plug with your 'powder... Mar 14 2025, 03:26 PM emerygt350 I chased what I thought was a lean miss for months... Mar 15 2025, 06:04 AM SVG223
I chased what I thought was a lean miss for month... Mar 15 2025, 02:53 PM SVG223
Agree with Superhawk.
All of the basics first
... Mar 15 2025, 01:35 PM ctc911ctc Strongly suggest that you buy this book, has saved... Mar 15 2025, 11:54 AM SVG223 Well, I tried the suggestion from @emerygt350 ab... Mar 15 2025, 03:35 PM emerygt350 Interesting. I would also check the coil too. Al... Mar 15 2025, 04:04 PM brant Doubt it is the distributor points for fuel inject... Mar 15 2025, 05:06 PM emerygt350 I had another thought as well... Does your car hav... Mar 16 2025, 05:32 AM SVG223
I had another thought as well... Does your car ha... Mar 16 2025, 02:03 PM JeffBowlsby A better price on the Tech Tips book - Direct from... Mar 16 2025, 08:13 AM SVG223
A better price on the Tech Tips book - Direct fro... Mar 16 2025, 02:05 PM emerygt350 The car will run fine without the TPS. It's o... Mar 16 2025, 03:55 PM SVG223
The car will run fine without the TPS. It's ... Mar 16 2025, 04:23 PM emerygt350 Excellent. Often that gets put on something...
W... Mar 16 2025, 06:23 PM SVG223 I found some play in the distributor shaft. I thou... Mar 16 2025, 09:40 PM emerygt350 Don't forget your dwell. That can make a big ... Mar 17 2025, 05:27 AM SVG223
Don't forget your dwell. That can make a big... Mar 17 2025, 02:04 PM SVG223 Now I'm thinking about buying a dwell meter an... Mar 17 2025, 01:51 PM emerygt350 Bad bearings can do that. If I were you I would j... Mar 17 2025, 02:56 PM FlacaProductions The petronix issue with leaving your ignition on w... Mar 17 2025, 07:25 PM SVG223
The petronix issue with leaving your ignition on ... Mar 17 2025, 07:28 PM SVG223 The vacuum retard diaphragm has a hole in it. That... Mar 17 2025, 07:27 PM emerygt350 Yeah, a hole there will just be a vacuum leak at i... Mar 18 2025, 05:24 AM SVG223
Yeah, a hole there will just be a vacuum leak at ... Mar 18 2025, 02:47 PM emerygt350 No, I have the non Bluetooth version and it has be... Mar 19 2025, 08:26 AM SVG223 I cleaned the distributor; the mechanical advance ... Mar 19 2025, 02:53 PM emerygt350 I would check your plugs and watch your head tempe... Mar 19 2025, 04:45 PM emerygt350 Oh, and did you get a dwell meter? Incorrect dwel... Mar 19 2025, 04:58 PM SVG223 duplicate Mar 19 2025, 06:15 PM SVG223 No dwell meter. I don't think this worn distri... Mar 19 2025, 06:15 PM ctc911ctc
No dwell meter. I don't think this worn distr... Mar 20 2025, 03:21 PM emerygt350 A poor spark can result in a miss. And don't ... Mar 20 2025, 05:30 AM emerygt350
I wouldn't ignore the dwell. Could be a re... Mar 20 2025, 06:37 AM ctc911ctc My 914 mentor, Richard Towle would say that for th... Mar 20 2025, 03:13 PM emerygt350 duplicate post Mar 20 2025, 06:37 AM SVG223
duplicate post
I ordered a Hot-Spark electronic ... Mar 20 2025, 02:39 PM brant a worn out distributor shaft will make a newer poi... Mar 20 2025, 03:26 PM brant I have a half dozen DJet distributors from differe... Mar 20 2025, 03:28 PM SVG223 It looks like I have about .005" of lateral p... Mar 20 2025, 04:42 PM |
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