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> NEED HELP: 1974 1.8L Will Only Start with Brake Clean, Runs with AFM disconnected only
Nor.Cal.914
post Sep 19 2024, 03:03 PM
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1975 914 3.0SC
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Hello everyone,

I have a 1974 1.8L that needs a new fuel pump and the customer purchased this pump from Pelican:

https://www.pelicanparts.com/More_Info/0439...59&DID=4630

I have already figured out the line routing in terms of inlet and outlet, but I do have a few questions about some other aspects. Being that the stock pump is a 3-port pump, first question is, what was the reasoning behind the 3 ports instead of just an inlet and outlet? My first thought was maybe an internal FPR, but I see there is a one in the engine compartment so that doesn't seem to be the case, but please correct me if I'm wrong! Second question involves mounting the pump. I have a 1975 so I'm not as familiar with how the 1974's were setup. This car has the coil style ring bracket around the pump which I'm now trying to figure out if I can utilize to mount the new pump. Main issue of course is the fact that all 3 lines came out on one side of the factory pump, whereas this pump has inlet/outlet on either side.

So my question is, what have you guys done to mount your pumps either in the same location or where did you place it instead of the factory location? Thank you in advance for the help! (IMG:style_emoticons/default/beerchug.gif)

-Christopher
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technicalninja
post Oct 8 2024, 09:53 AM
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My units have 7 pins!
Check your connector that plugs into the AFM. Does it have 7 recesses (one of which is "un-populated").

If it does, I believe we can make it work.


The flap should ONLY flutter if the engine is being cranked!!!!!

If it's moving at all when the engine is not that's double headed weird!

There's nothing inside an AFM that should move the flap electronically.

Most of the time the extra pin is for fuel pump "on" signal 6 vs 7.
I can work around that easily.
Some run the extra pin for a IAT sensor.
Both are not a requirement for system functionality.

Yes, they are needed for daily operation but not to turn fuel to fire.

The fuel pump drive signal is one of the "normal" failure points and is often bypassed by previous owners.

Most of the time it's a bad contact point inside the AFM and cleaning/adjusting the contact will fix it.

Your deal of no pump with AFM installed and pump with AFM discoed sounds like someone has modified the fuel pump electrical circuit to me.

I also have injector pulse equipment.

I have 10 tons of tools.

Been doing this shit 40+ years...

I can also fix the AC in your daily drivers!

The "way" I'd start diag on your car is to direct drive the pump (jumper with circuit breaker) and get the system running before I attacked the fuel pump circuit.
It's secondary to FI function IMO.

I'd also "base line" the engine with a comp test.

I can usually achieve function with a can of B12 to the point of heating the engine up and/or moving it around.
I hate pushing cars...
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Posts in this topic
Nor.Cal.914   NEED HELP: 1974 1.8L Will Only Start with Brake Clean   Sep 19 2024, 03:03 PM
Geezer914   Get a Delphi pump from Rock Auto for $108...   Sep 19 2024, 03:37 PM
Nor.Cal.914   Get a Delphi pump from Rock Auto for $108...   Sep 19 2024, 03:57 PM
Artfrombama   Get a Delphi pump from Rock Auto for $108...   Sep 19 2024, 04:02 PM
wonkipop   have rebuilt two of the old bosch 3 port pumps. li...   Sep 19 2024, 04:52 PM
Nor.Cal.914   have rebuilt two of the old bosch 3 port pumps. l...   Sep 23 2024, 08:45 AM
wonkipop   and yes you will have a bit of trouble mounting a ...   Sep 19 2024, 05:10 PM
wonkipop   postscript. went back and re-read my own thread t...   Sep 19 2024, 05:47 PM
dr914@autoatlanta.com   we sell the conversion kit for 125.00 that include...   Sep 23 2024, 08:47 AM
Nor.Cal.914   we sell the conversion kit for 125.00 that includ...   Sep 23 2024, 09:29 AM
StarBear   Weird that it runs only with the AFM disconnected....   Sep 23 2024, 09:55 AM
Nor.Cal.914   Weird that it runs only with the AFM disconnected...   Sep 23 2024, 10:49 AM
Artfrombama   Forgive me if you have already done this but have ...   Sep 23 2024, 11:50 AM
Nor.Cal.914   Forgive me if you have already done this but have...   Sep 23 2024, 03:33 PM
wonkipop   here is what i think. a few us here with 1.8s hav...   Sep 23 2024, 05:22 PM
Nor.Cal.914   here is what i think. a few us here with 1.8s ha...   Oct 7 2024, 03:06 PM
Nor.Cal.914   Here are some pictures of the engine bay. If there...   Oct 7 2024, 03:15 PM
Nor.Cal.914   Last one:   Oct 7 2024, 03:15 PM
wonkipop   @[url=http://www.914world.com/bbs2/index.php?showu...   Oct 7 2024, 05:25 PM
fiacra   A few thoughts that came to mind when reading your...   Oct 7 2024, 06:30 PM
wonkipop   here is a direct link to the L jet troubleshooting...   Oct 7 2024, 09:28 PM
wonkipop   ok @[url=http://www.914world.com/bbs2/index.php?s...   Oct 7 2024, 09:53 PM
wonkipop   looking close at one of your photos. something see...   Oct 7 2024, 10:24 PM
L-Jet914   That caught my attention too @wonkipop the wire ...   Oct 7 2024, 10:56 PM
wonkipop   That caught my attention too [b]@[url=http://www...   Oct 8 2024, 12:30 AM
wonkipop   i just noticed another thing. the fuse board or wh...   Oct 8 2024, 01:03 AM
Nor.Cal.914   A few thoughts that came to mind when reading you...   Oct 8 2024, 08:33 AM
wonkipop   @[url=http://www.914world.com/bbs2/index.php?showu...   Oct 8 2024, 04:17 PM
wonkipop   Some other things I found this morning while testi...   Oct 8 2024, 10:52 PM
technicalninja   Hello from Granbury Texas! I have a shitload ...   Oct 8 2024, 08:59 AM
Nor.Cal.914   Hello from Granbury Texas! I have a shitload...   Oct 8 2024, 09:14 AM
technicalninja   My units have 7 pins! Check your connector tha...   Oct 8 2024, 09:53 AM
technicalninja   If the fuel is poisoned, you have to clear that fi...   Oct 8 2024, 10:59 AM
technicalninja   MOST IMPORTANT TIP!!!!!!...   Oct 8 2024, 11:13 AM
Nor.Cal.914   My units have 7 pins! Check your connector th...   Oct 8 2024, 02:58 PM
Artfrombama   Is the fuel injection trigger wire connected to th...   Oct 8 2024, 06:31 PM


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