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Discussion Starter #1
I'd like to ask for opinions on this if I may.
I replaced both relays for the fuel pumps. Now the parts store gave me an incorrect bosch relay to replace the main relay. When I figured that out, I replaced it with an actual Alfa relay and it now works.
The fuel pump drive relay however, is another bosch part, and I don't have the part number in front of me. It plugged directly in.

I'm starting to think that the fuel pump drive relay I have is wrong because when I turn the key to run, the pumps power up and stay on.
I've seen here they're supposed to cycle for less than a second unless the engine is cranking or running.

I think this relay is running the pumps on its timer circuit for about 15 seconds, then shutting down. This would explain my stalling. The engine will start and run for about 15 seconds. [not very well, but it does start]

Any ideas? THink this is a viable theory? Since one relay plugged in and was wrong why wouldn't the other be?
Thanks for any opinions or ideas.
 

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Discussion Starter #3
OK...I got some more info. The relay is a K A E 3 304 500 fuel pump relay. The pins match the wiring schematic I have. It clicks on when the key is turned. The pumps start up and don't go off. They go on until I turn the key off.

I'm going to google this for its interchange. Anyone use this relay or have the part number for the correct one?

Second question; is there a way to check for the tach pulse in the white wire? Since the car starts, it is getting a pulse but I'm thinking maybe it loses the pulse for some reason. THat would stall it, right?
THanks
 

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Discussion Starter #4
I Googled and found this:
http://www.alfabb.com/bb/forums/spider-1966-up/183805-fuel-pumps-runs-constant-when-key-position.html

So it seems others have used this relay and their pumps stayed on but their cars ran. I'm starting to think this relay is N/G anyway since the timer circuit is not timing. I had the key on engine off for 20 sec. both pumps whirring away.
On a hunch I added 3 gals of gas to the tank, no difference.

It tries to run, runs for about 10-15 secs than just dies. Very strong "catalytic converter" smell. Will start again and repeat the cycle maybe twice more. Let it rest and it goes through the routine again.

Could it be running on the cold start injector only, then when that goes off nothing from the regular injectors?
I checked for injector pulse and there is injector pulse.
Car sat for 7 years, stuck injectors? Any way to test or tell?
Thanks
 

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Discussion Starter #5
Did another test. Hooked up a timing light and started it. Steady spark for the 10-15 seconds it runs then the spark dies. I've been chasing my tail with fuel.
Guess I'll check out the ignition threads. There's not much to that system right? The ICU runs it and nothing really happens in the distributor, right?
 

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Guess I'll check out the ignition threads. There's not much to that system right? The ICU runs it and nothing really happens in the distributor, right?
About right. The distributor is really just a four position switch to send coil output to the appropriate spark plug.

Check the flywheel sensors (info in the L-jet diagnosis page link in my signature).
 

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Note however that the KAE relay bypasses an important safety feature of the Bosch relay. The fuel pumps should only pump with the engine running (or the key in the 'start' position). With the KAE relay it could keep pumping fuel in the event of an accident even if the engine stalled.
 

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Discussion Starter #8 (Edited)
I checked the ohms on the 2 crank position sensors.
I got 1006 on one and 985 on the second.
Seems to be within spec....
but that doesn't mean they're still not bad
 

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Discussion Starter #9
Note however that the KAE relay bypasses an important safety feature of the Bosch relay. The fuel pumps should only pump with the engine running (or the key in the 'start' position). With the KAE relay it could keep pumping fuel in the event of an accident even if the engine stalled.
Yes...I see that. Troublesome. Are any of the other cross referenced relays equipped with that feature?
 

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Did you check that they are connected to the wire harness correctly? There is a black connector & a gray connector. One is for the upper sensor, the other for the lower. Although the sensors are identical, they must be plugged in correctly.
 

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Discussion Starter #11
I don't specifically remember that, but nothing jumped out at me when I checked them. I'll get back to the car on Mon or Tues and verify
 

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Hello. Still 83 spider wont run. Once I plug in maf car cuts off. Swapped out maf and fi computer still cuts off. I found out that the o2 sensor wires are not connected. They are cut.
 

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I'm out of ideas. I replaced fuel pumps aND crank sensor because car wouldn't even turn over but it's running with maf not plugged in. I noticed that if I unplug the tps the car doesn't even acknowledge it wondering if that is faulty.
 

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Hello. Still 83 spider wont run. Once I plug in maf car cuts off. Swapped out maf and fi computer still cuts off. I found out that the o2 sensor wires are not connected. They are cut.
Probably need a lot more information to figure out what's going on, but below is a link to a long thread where someone had a similar issue in that the car would run with the AFM unplugged but not if it was connected. Read through the thread, but I think he determined it was a fuel-pressure issue.

http://www.alfabb.com/bb/forums/spider-1966-up/465530-afm-plugged-kill.html
 

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I'm getting infinite when I go from 2 and 18 on tps and infinite from 3 to 18 while tps is closed. Furum says I should be getting zero from pin 2 and 18. Does this mean it's faulty.
 

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I'm getting infinite when I go from 2 and 18 on tps and infinite from 3 to 18 while tps is closed. Furum says I should be getting zero from pin 2 and 18. Does this mean it's faulty.
In my experience, the car will run even if the TPS is not hooked up. But do you hear the very faint "click" when you just start to open the throttle? If not, you should first try to adjust the position of the TPS.
 

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Ok thanks for the feedback. Just got the car running with the afm plugged in by opening the flap on the afm with a screwdriver.
 

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I'm getting infinite when I go from 2 and 18 on tps and infinite from 3 to 18 while tps is closed. Furum says I should be getting zero from pin 2 and 18. Does this mean it's faulty.
If it is still connected to the throttle body, you may need to loosen the two screws that secure it to the throttle body, rotate the switch one way or the other a bit and re-test.

I had a TPS once that would return the proper readings on the meter, but only when it was clocked on the throttle shaft in such a position that the two screw slots would not line up with the mounting holes in the throttle body. I couldn't use that one.

You may have a faulty TPS, or the wrong one. I had a bad one on my car, and bought a used one that also didn't provide the proper multi meter outputs. Then finally got another used one that worked properly. So I can attest that they aren't all that durable.

It's also important that you have the correct TPS for your car. Bosch made several of these switches in the same housing but with slightly different clocking for different throttles/applications. Check the part number embossed on the face of yours. I'm pretty sure your '85 Spider came with a Bosch 0 280 120 304.
 

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Just got the car running with the afm plugged in by opening the flap on the afm with a screwdriver.
This makes me think you have the air duct (black plastic hose thing) not attached. If so, propping open the flap is simply tricking the computer into thinking that the engine is drawing in air.

What happens when you re-attach the air duct? If there is an air leak then the engine will draw in 'false air' - unmetered by the AFM - and the computer will not get a valid 'inject fuel' signal.

Does the flap move smoothly without undue resistance? There should be slight spring tension but it must not stick in any position (like closed...).
 
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