D-Jet Conversion not going as planned., Car starts but will not run. |
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D-Jet Conversion not going as planned., Car starts but will not run. |
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Oct 18 2024, 03:08 PM
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#1
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Member Group: Members Posts: 109 Joined: 11-June 23 From: Utah Member No.: 27,409 Region Association: Rocky Mountains |
I am converting back to D-Jet and my car will start but dies right after. It will not rev up applying throttle. I have a 1975 914 2.0. It was running great with Weber 40s prior.
The D-Jet system is from a 1974 2.0. All the parts came in visibly good condition. TPS calibrates good, AAV tested good, Thermo sensor good, air intake temp sensor good, and a new cylinder head temp sensor. The only test that I think is failing is the vacuum test on the MPS. It leaks. Video of testing the MPS.. The MPS has also been rebuilt at some point. The original part # has been removed. There's a good chance it is not calibrated for my car. I have all new vacuum hose and fuel pressure is between 28 and 30. I don't have any tools to calibrate the MPS. Should I try turning the inner screw on the MPS to see if it helps? Or should I send it to someone to have it rebuild again and recalibrated? If the later do you have any recommendations on who to send it to? |
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Oct 25 2024, 08:42 AM
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#2
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Member Group: Members Posts: 109 Joined: 11-June 23 From: Utah Member No.: 27,409 Region Association: Rocky Mountains |
With the smoke test, I get smoke coming out each side of the throttle shaft. Is there a bushing kit for this? Is it rebuildable or can I pack with grease?
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rjames |
Oct 25 2024, 12:37 PM
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#3
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I'm made of metal Group: Members Posts: 4,145 Joined: 24-July 05 From: Shoreline, WA Member No.: 4,467 Region Association: Pacific Northwest |
With the smoke test, I get smoke coming out each side of the throttle shaft. Is there a bushing kit for this? Is it rebuildable or can I pack with grease? Each side? Assuming you've sealed the top of the TB when testing, there are only 3 possible areas from the TB itself where leaks could occur (unless there is a crack somewhere): Idle screw Vacuum port 1 (for advance- facing rear of car) vacuum port 2 (for retard facing front of car- not all cars had this port) When doing the smoke test, plug both vacuum ports. Are you sure the leak isn't coming where the throttle body sits on the plenum? You may just need to tighten the bolts holding it down, or more likely you need a new throttle body gasket. |
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Oct 25 2024, 01:02 PM
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#4
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Member Group: Members Posts: 109 Joined: 11-June 23 From: Utah Member No.: 27,409 Region Association: Rocky Mountains |
With the smoke test, I get smoke coming out each side of the throttle shaft. Is there a bushing kit for this? Is it rebuildable or can I pack with grease? Each side? Assuming you've sealed the top of the TB when testing, there are only 3 possible areas from the TB itself where leaks could occur (unless there is a crack somewhere): Idle screw Vacuum port 1 (for advance- facing rear of car) vacuum port 2 (for retard facing front of car- not all cars had this port) When doing the smoke test, plug both vacuum ports. Are you sure the leak isn't coming where the throttle body sits on the plenum? You may just need to tighten the bolts holding it down, or more likely you need a new throttle body gasket. From what I could tell it is coming from both sides of the shaft holes. nothing from the new vacuum hose on the body. The gasket on under the TB is new. I'll check the bolts again. |
Lo-Fi Version | Time is now: 28th November 2024 - 04:39 AM |
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