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Discussion Starter #1
Hi,
Would anyone know how I would test a fuel pump relay and related values to detemine if it's bad or not? 1.8 mV at fuel pump terminals tells me that there is no power there. The only thing I can think of is the relay.
All manuals make no mention of values, or even specific location on where to find the relay. '88 spider veloce. thanks for any help.
frankao
 

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1966-2013
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That'll be the larger of the 2 relays underneath the cargo panel behind the seats, right side, next to the ECU. The fuse for those relays is right there also. (might not hurt to confirm that's in god shape, clean, and well connected before worrying about the relays....)

I'm a bit fuzzy right now and not near any of my information, so I don't readily recall which terminal is the actual fuel pump(s) terminal on that.


However, that specific relay is a tachymetric tpye, meaning it has to get a pulse signal from the ignition coil to turn on. (as in you won't be able to test it in a conventional fashion with a multimiter, but will have to leave it hooked up and check it while cranking the engine. No spark, no signal, no signal, no pumps)

It also is the trigger source for the for the injectors (the small one right there) so if your injectors get a signal while cranking, (whether the pumps come on or not), you know the relay is likely good and the issue lies in the wiring between that relay and the pump(s).

As yours is an '88, it'll likely not have it, (stranger things have occured though), but it could be worth looking for an inertia switch up by the windshield washer resevior and seeing if it's clean, connected well, and actually making contact. (about the size of a pack of cigarettes with a button on it)
 

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Discussion Starter #3
Thanks Tifosi. But, wouldn't simply by turning the key to start cause the pump to turn on to pressurize the fuel system? Since the fuel systems needs about 35 psi the pump should have power to it, no. I don't hear the anything turn on except for the instruments when I put the key into start position. This leads me to believe that either the pump is bad, or there is no power to it. In which case I tested power to the pump.
Am I missing something here?
Thanks
 

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1966-2013
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'Tachymetric relay' ;)

When you first turn the key on, you may or may not hear a quick pulse of the fuel pumps, but that's it until you actually crank the engine and the coil starts sending a pulsing signal to the relay which in turn turns it 'on' and begins operating the pumps full time. (it's set up so if you smash yourself, the pumps cut off when the engine does)
 

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Discussion Starter #5
hi and thanks again,
OK that made it clear. I crank and at the pump I get 9.8 V. Is that a good value? Not sure it is. In looking at the relays, the relays that I have do not look anything like the ones I see posted in the ljet help pages, leading me to believe that they may not be the proper ones or they are bad. I'll include a pic here. Maybe you can help me figure what's going on with this. The whole point here is I'm not getting any gas for the CST, all values on sensors are good so that's whats leading me to the pump and now the relays. Comments.
Thanks
ps good to know the Alfa engineers designed the pumps to shut down on impact. Warm and fuzzy all over.
 

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Discussion Starter #6
pic of relays One if marked fuel pump relay. in alpha terminology is that the drive relay, the small metallic relay I assume is the main relay. Correct me if I'm wrong. thanks
 

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You are correct.

However, they should be anchored for thier own durability, as should the fuse.

You should be getting 12v at the pumps, not 9.8V.

If that's during cranking as you describe, it ain't gonna touch off anyway as the ECU needs 10.3-10.5 volts during cranking to even fire off.


Query:

Where does that black with white trace (or white with black trace) wire that looks like it's cobbed into the rightmost terminal of the small relay go?

Whatever it it, it ain't right and someone has been tinkering around.



Actually, I'm curious about another thing too:

That's the ECU to the right of the relays.

The ICU is in the vertical panel to the left behind the carpet.

But what is that box that the relays are laying on?

I've never seen such a thing.
 

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Discussion Starter #8
Thanks,
Great at lest I know I'm on the right track. So I take it then that the pump relay is not outputing the correct voltage, which means that it is a bad relay? How can I confirm that this is bad or might it be the main relay or both?

The white/black was grounded to the mounting bracket for the box on the left. I'll take it off. it was there upon first observation, have no idea what it is doing there.
The box on the right I think is suppose to the ICU, it was not mounted to the interior sidewall of the body and found exactly as you see it there. Interestingly enough, the Altitude compensation device is mounted in the side wall.

Thanks for your help. really appreciate your depth of knowledge here and on other posting where I've seen you input.
Cheers
 

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Discussion Starter #9
quick note. tested the main relay without the grounding wire. Cranked the motor. guess what? .3 volts. screwed it back into place to ground, back to 9.8 V. Grounding makes a difference, but still not enough voltage to kick the fuel pump over. Would the main relay be bad with these symptoms?
Thanks
 

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1966-2013
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You might want to be checking your battery voltage, both static and during cranking to see if it's on the weak side.

Static is easy enough, just throw a multimeter across the terminals, then again across the harness connectors. (first to see if the battery has guts, 2nd to see if it's making it through the connectors)

When cranking (well, when someone else is cranking for you) check at the harness connectors first (to see if the circut even gets that far with some gumption) then at the terminals directly.

Anything below, say, 10.7 volts and you're not going to get anywhere.


Odd that wire would be cobbled like that, as there's a ground elsewhere for the relay and is part of the regular wiring off the plug for it. (well, should be anyway)

Someone's been up to something methinks. (you might want to try and contact papjam for a most excellent wiring schematic so you can chase proper-like)
 

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Discussion Starter #11
Cool, I checked the battery and found that it didn't have enough cranking amps. Exchanged and voltages are all in line with what they are suppose to be. Fuel pump, no workee. OK thinks thats the problem so I'll chase that down. Thanks again. Will let all know if succesful.
 

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Discussion Starter #12
Got the fuel pump in, checked the CSI. all OK. Turn it over and blow the air plenum off of the intake manifold. Reattach, crank, then blow the airways to the plenum off. Sounds like pre-ignition, at lease I'm getting fuel where I had none before. Plugs are incorrectly, so what else could be doing this? Ideas?

Thanks
 

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Click into my sig link again when you get time and check the ignition section in regard to the timing and the little tick mark on the dizzy body that orientates #1 postion on the cap if you're at TDC on compression.
 

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Discussion Starter #16
Thanks, set it all up correctly P mark on crank, number one cylinder, verified firing order and dizzy wire locations, and blew the plenum off the manifold again. Something seems like it's missing. Before I bought the car, the guy who had it had the top end done and never fired it up afterwards, could it be that this may have something to do with it? Seems like something is firing out of order, but after this, I'm sure it's nothing to do with the "normal" distribution of spark. Ideas? Thanks
 

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Discussion Starter #18
firing order verified as correct.
Clearances, don't know. havn't pulled the cover off yet and also need to check if the cam timing is correct. If it's the cam timing, all explained.
Was looking to see if there would be something I'm overlooking as I don't know this injection system well. Thanks
 

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Definitely check cam timing. Position the engine back to TDC on #1 cylinder. The cam lobes for #1 should be facing away from each other (intake pointing right, exhaust pointing left). The small timing mark on the front of each camshaft should align with a mark on the back side of the forwards cam cap.

While the can cover is off, check the tension of the timing chain. It should be fairly taut between the two can gears.
 

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Discussion Starter #20
Interestingly enough, after removing the cover I find that the the notches are aligned, but the lobes on either side are pointed inward. I think they should be pointed outward, no? Engine is at TDC on #1. If these are supposed to be pointed outward, then I think I have the problem found.
 
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