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| shredtherad |
May 27 2022, 05:08 PM
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#1
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Member ![]() ![]() Group: Members Posts: 86 Joined: 17-May 22 From: Longmont, Colorado Member No.: 26,559 Region Association: Rocky Mountains |
Hello, hello! The new to me 914 is so rad! Love it... went out for a bit of cruise and about 20+ mins into the drive, while approaching a trafific light ( red ) the car came down to idle and that kept going and poof... stall. It did not start, I blocked the lane and angry SUV's and Tesla's honked at me. I did however get it going again after putting the pedal to the floor while starting and it fired up and drove fine, until... idle at the stop sign. Poof, stall. BUT this time pedal to the floor and fired right up.
Thoughts, where should I begin. I have attached a video of the issue... thanks! Beep Beep. https://www.youtube.com/watch?v=Mx47LENYFuU |
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| mgphoto |
May 27 2022, 09:57 PM
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#2
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"If there is a mistake it will find me" ![]() ![]() ![]() Group: Members Posts: 1,425 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California |
First test is simple, get a hand vacuum pump with a gauge, test the MPS, pull 10 to 15 in Hg and see how long it takes to drop.
Sounds like a cracked diaphragm, runs rich when that happens. |
| GregAmy |
May 28 2022, 06:53 AM
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#3
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,651 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States
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First test is simple, get a hand vacuum pump with a gauge, test the MPS, pull 10 to 15 in Hg and see how long it takes to drop. Sounds like a cracked diaphragm, runs rich when that happens. Was my first thought, since I had similar symptoms with the 2L D-Jet. If you're running stock D-Jet, and you have more than say, 75-100k miles on the car, you have no evidence that the diaphragm has ever been replaced, then I'd wager a dollar to every donut that your diaphragm needs to be replaced. The MPS was a very clever design for its time but that diaphragm has a life limit before it will absolutely fatigue. Mine had those, and other symptoms, and it actually passed the vac test! But when Tangerine pulled it apart to rebuild the crack was obvious. And replacing it transformed the way the car drove. I like D-Jet, I think it's worth saving. Consider sending your MPS to Chris for a new diaphragm, even if it passes a vac test. http://www.tangerineracing.com/mpsdiaphragm.htm |
| shredtherad |
May 28 2022, 09:00 AM
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#4
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Member ![]() ![]() Group: Members Posts: 86 Joined: 17-May 22 From: Longmont, Colorado Member No.: 26,559 Region Association: Rocky Mountains |
First test is simple, get a hand vacuum pump with a gauge, test the MPS, pull 10 to 15 in Hg and see how long it takes to drop. Sounds like a cracked diaphragm, runs rich when that happens. Was my first thought, since I had similar symptoms with the 2L D-Jet. If you're running stock D-Jet, and you have more than say, 75-100k miles on the car, you have no evidence that the diaphragm has ever been replaced, then I'd wager a dollar to every donut that your diaphragm needs to be replaced. The MPS was a very clever design for its time but that diaphragm has a life limit before it will absolutely fatigue. Mine had those, and other symptoms, and it actually passed the vac test! But when Tangerine pulled it apart to rebuild the crack was obvious. And replacing it transformed the way the car drove. I like D-Jet, I think it's worth saving. Consider sending your MPS to Chris for a new diaphragm, even if it passes a vac test. http://www.tangerineracing.com/mpsdiaphragm.htm https://youtu.be/3lvTXN7d5-8 This seems like a good video/resource |
shredtherad Honk Honk!.... " yea, I know I am stalled out and blocking the intersection @$$H*L$" May 27 2022, 05:08 PM
Big Len I think the first general question would be carbs ... May 27 2022, 05:22 PM
shredtherad
I think the first general question would be carbs... May 27 2022, 08:45 PM
emerygt350 So sorry! What is the year and fuel system? C... May 27 2022, 05:23 PM
shredtherad
So sorry! What is the year and fuel system? ... May 27 2022, 08:45 PM
Superhawk996 Watched your video. By video title it says stock ... May 27 2022, 05:44 PM
shredtherad
Watched your video. By video title it says stock... May 27 2022, 08:48 PM
r_towle
[quote name='Superhawk996' post='3004559' date='M... May 28 2022, 08:52 AM
shredtherad
[quote name='Superhawk996' post='3004559' date='... May 28 2022, 08:57 AM
76-914 So it takes about 20 min's before this happens... May 27 2022, 05:58 PM
shredtherad
So it takes about 20 min's before this happen... May 27 2022, 08:50 PM
wonkipop factory workshop manual
you can download.
http:/... May 27 2022, 08:47 PM

shredtherad
First test is simple, get a hand vacuum pump wit... May 28 2022, 08:57 AM

Lockwodo
[quote name='GregAmy' post='3004653' date='May 28... May 28 2022, 10:31 AM
shredtherad
First test is simple, get a hand vacuum pump with... May 28 2022, 08:56 AM
brant Can you hear the pump run when it’s acting up an... May 29 2022, 06:56 AM
shredtherad
Can you hear the pump run when it’s acting up a... May 29 2022, 08:31 AM
rhodyguy This is a MittyvacII. You will know if the diaphra... May 29 2022, 08:35 AM
shredtherad
This is a MittyvacII. You will know if the diaphr... May 29 2022, 10:49 AM
shredtherad All, thanks for the replies and insights
I teste... May 29 2022, 10:54 AM
brant So that creates an ultra rich condition and the re... May 29 2022, 12:40 PM
brant There is also an O’ring inside to seal the MPS c... May 30 2022, 09:04 AM
shredtherad
There is also an O’ring inside to seal the MPS ... May 30 2022, 05:45 PM![]() ![]() |
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