Conversion back to EFI, from single carb |
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Conversion back to EFI, from single carb |
billd |
Jul 14 2005, 05:55 PM
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#1
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Member Group: Members Posts: 327 Joined: 25-May 05 From: Palo Alto, CA Member No.: 4,145 |
I am considering converting my 73 2.0L back to D-Jetronic EFI. The PO converted it to a single 2-barrel progressive carburetor. I have a few questions.
Fuel lines. Currently there is no return fuel line and the PO has run the supply line with 3/8 copper tubing down the right (passenger) side of the car (not through the tunnel). The fuel hose on either end appears to be clamped directly to the copper tubing - no AN fittings. My thought was to run a second 3/8 copper tube along the same path as the supply tube for the fuel return (sharing grommets). Is this routing reasonable? or should I relocate both tubes back to the tunnel? Is copper a reasonable material for this or should I use SS line? Is it OK to clamp the hose directly to the tube in a high-pressure EFI system? (This doesn't seem like a great idea to me since there doesn't appear to be anything keeping the hose from getting pushed off the end of the tube by fuel pressure). If not, what type of fittings do you recommend? I was thinking of flaring the tube ends and using AN fittings. Component Locations. I have all of the pieces from the D-Jetronic that was removed: fuel pump, pressure regulator, rails, injectors, throttle body, MP sensor, control module. However, its not clear where they are supposed to be mounted. Can anyone point me to a picture that shows the original locations of these components on a 73. (Its pretty clear where the injectors, rails, and throttle body go, but the other components could be bolted almost anywhere). Unit testing. While I'm hopeful that everything works, being realistic one or more of these 33 year old components is probably out of spec. For the fuel pump, regulator, and injectors the unit test is pretty simple, but what about the MP sensor, temp sensor, and control unit? Does anyone have an easy way to unit test them? Thanks much for the help. |
brant |
Jul 15 2005, 09:22 AM
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#2
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914 Wizard Group: Members Posts: 11,638 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
my guess is that the previous owner removed the fuel injection and installed the carbs because the injection was malfunctioning.
The prime reason for going over to carbs is because people either can't figure out why, or don't want to spend the money to repair the fuel injection... so I'm 99.999999% sure one of your F.I. components is bad. the brad anders site listed above has all of the tests for every single component. before you put your car up onto the proverbial jack stands, I would test all of the components and get all of necessary parts/pieces you will need. you don't want to go through all of this only to find that it doesn't run at all when your done. Plus diagnosing problems is tough enough on a job like this when you don't even know if the problem might be a component or a wiring harness, or a relay board or whatever. brant |