924Board.org

[77924pporsche]

ohk to start off i have a 77 924 porsche, i have already replaced many things in the engine. Im having a problem tho, i changed the spark plugs but no where has my wires they would have to order them so the car is out of commision i went to the junk yard today and got some spark plug wires that fit off of a vw bring them back and put them on go to turn over my car and i notice my fuel pump doesnt kick in. my fuel pump was working last night. im getting fed up please help me
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77 924

[scm924s]

If your car still has original wiring, etc., you should be able to remove the air filter box cover and filter, switch on ignition and put your hand up into the top RH side and gemtly lift the lever in there. The pump should then run, if not remove the fuel pump relay, relay board top row second from left, should be a 6 pin relay with a 16amp fuse on top (check fuse), and bridge socket connections with a jumper wire fitted with 2 spade terminals to fit terminals 30 and 87. this should cause the pump to run straight away without ignition, for safety's sake it is better to have an inline 16amp fuse in the jumper.

If pump doesn't run, the pump is likely to be unserviceable. Do not leave the jumper in place. If pump does run, probably relay is at fault. The original relay is NLA, and I don't know what the alternative is unfortunately!

You could try a separate 12v supply direct to pump connections just to ensure there isn't a wiring fault.
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1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[jim kleyh]

I keep reading about the elusive fuel pump relay which is NLA. There are many auctions that are listed as being 924 pieces. Are they garbage or ?? I'm in the same position right now and was and still am worried where I'd go to find a suitable relay.
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oldcarman-77 porsche 924 and one of the ugliest motorhomes on earth.

[scm924s]

There are different FPR depending on year. Up to 1978 was a 6 pin relay with a top mounted 16amp fuse. These early cars had no separate auxiliary fuse panel and this FPR fuse is the only protection to the fuel pump circuit. Late 78 on had a 5 pin relay with slightly different circuitry and no attached fuse, I don't believe this can be used on early models, these later cars had the aux fuse panel and the pump circuit is fused there. The 924S has a different FPR altogether, as did the Turbo.

It would be helpful if someone with far more tech knowhow than me could advise on possible alternatives to this early FPR, there is a VW golf/rabbit GTI (I think) 5 pin relay with fuse with similar pin notation to the 6 pin (less 1) which looks a possibility, but I don't have the courage to try it!
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1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[Gene]

Did you ever check the fuel pump by running battery current to it directly yet ? My two convertable Rabbits had sat for 2 years and fuel pumps wouldn't turn over when I hot wired them this way so I took them off the cars and tapped them on a block of wood and a lot of crap came out of them, put them both back on and now they both pump fuel now. Wouldn't want to do a cross country trip with them though.

[CorsePerVita]

Quickest way and easiest route to testing your fuel pump.

Step 1. Pull the plug off the fuel pump. Using 2 test wires, hook it up to a known working 12v battery. It should kick on. If it doesn't, you have a pump issue. If it turns on, great.

Step 2. Testing on/off. Take the boot off of the metering plate. Turn the car to "on" (NOT START, just ON) and lift up the plate. With the car ON, again, NOT start and the plate lifted UP you should measure 12v at the plug for the fuel pump. If you do not, the issue is with the switch on the metering plate or the relay or the circuit.

Step 3. If you don't get 12v at the plug with the plate up and car on then remove the relay and use a jumper wire on it to bypass the relay. If you get 12v at the plug then the issue is your relay. If you do not, then it's time to test the switch on the metering plate.

These are the most basic and common things on the fuel pump to check. Hope it helps.
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- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

[pmcaya2]

I'll post a follow-up when I review my experience with a fuel pump relay. I did have one go bad and it was a sporadic failure. One day the car didn't want to finish the trip to work. I returned to the car after work and it started. I recall that the relay was easy to obtain - take the old one to the parts store and find a match - they didn't make a special one for the 924 and they are <$15. Might be best to simply replace it and see what happens.
Anyway, I'll post more later. Good Luck - Peter

[scm924s]

As far as I am aware the early fpr is Porsche specific, and it is fused. Do not replace an early one with a non fused one as there are no other fuses in the system for the pump. Other fpr may fit but are not correct.
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1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[brealytrent]

had to replace the fuel pump relay in my car, and yes, there is a fuse at the end. You can find them, but they are about $100 a piece. Hopefully that's not the problem.
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1977 Porsche 924 - sold
1980 Porsche 931 - sold
1984 Porsche 928 'S2' Euro - sold
2016 Ford Fiesta ST - sold
2009 Porsche Cayman

[snakoil]

or you convert you fuel pump system to use the 78 and up relay
the relay cost 30$ and is made from K.A.E.
then you put a 16amp fuse on the 87 wire right after the relay with the 6th wire (who I assume is used as ground for the fuse)
This is all there is to the 78+ update so you can easily convert for less than 40$

beware as I did got a brand new KAE relay and it was D.O.A., took me time to figure this one out
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1979 924 NA

[scm924s]

Sounds an excellent idea. For those, like me, who are electrically challenged, is this still a 6 pin relay, and is the 87 and earth the same wire?
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1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[!tom]

The '78 relay has a fuse on it.
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78 924 NA
5-lug