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Discussion Starter #1
Hi everyone, I'm hoping I'm posting in the correct forum. A little background info, i have an 1987 spider veloce, been trying to restore it for the past 6 years now, I've rebuilt almost everything on this vehicle, even hopped up the engine. Currently I'm stumped right now my car has no fuel injector pulse at all all the grounds are there and all the power is there i was suspecting a bad ecu so I went to a local shop and have them test it on their spider and it worked fine, can a napa fuel pump relay make all the difference, also I tried going for an electronic distributor but that went up in smoke so now I'm using a points distributor and I'm aware that that battery voltage has to be above 10.5v, tts works, cold start injector works, main injectors work. If anyone can help me with this issue I'll be very grateful. And also the noid light does not blink and both wires at the injectors have power.
 

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Welcome to the AlfaBB. Before we can properly diagnose these types of problems we need to know all the details about your car. Like what color is it? That's where pictures are so useful. Therefore we suggest you post some. Besides, we like pictures!

Click on my signature for a link to a page of DIY diagnosis of the L-jetronic system in our cars. L-jet is a system - all the parts have to work for it to work at all. Check the flywheel sensors - there are two: one for position (timing) the other for speed (rpm). Both need to be working and connected to the wire harness correctly.

Have you checked for spark? The drive relay needs to receive a signal from the coil to know the spark plugs are firing. It then sends power to the fuel pumps (there are two - powered together). No spark = no fuel injection.

(don't forget the pictures)
 

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Discussion Starter #3
So the alfa has a candy apple red color, i hopped the engine with parts from spruellmotorsports, like 10.1:1 pistons, king bearings, better connecting rods, timing chains, the whole shebang apart for the camshafts because of the vvt, i still have the original distributor for the engine (the empty one that only has the rotor) but i put in a points distributor just so I can run it out of the car on a stand with some carburetors. I have checked for spark and it is strong and in the correct firing order. So the questions I've got are:
Can a napa brand fuel pump relay (the bigger of the two relays next to the ecu) be affecting the fuel injectors, if so I'll get the correct one.

Does the car really need both ignition and fuel ecu's to run, can it run on the fuel ecu only with a points distributor or the electronic distributor, last night I did some more digging and gave the fuel ecu a better ground and now the noid light comes on when cranking but does not flash. I will try to post more pics and provide more information as the only time for me to work on the car is in the morning before work and after work for about and hour or two, here being winter and all.
 

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Post a picture of the fuel pump relay your talking about.
 

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Does the car really need both ignition and fuel ecu's to run, can it run on the fuel ecu only with a points distributor or the electronic distributor,
Yes, it can run without the ignition ECU if you install an alternate system. I haven't done this but I know others have.

The drive relay is the larger of the two located near the fuel ECU (under the shelf behind the seats). There is a replacement KAE brand that fits but may not work properly. The KAE relay may not cut power to the fuel pumps if the engine is not running (as might happen in an accident). This is a safety issue.

You can bypass the drive relay by making a jumper wire to connect terminals 30 & 87. This is just to test that the rest of the systems are working. It would not be safe to drive the car that way - bypassing the safety issue of a properly functioning drive relay.
 

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Discussion Starter #6
Yes you are correct, i have the KAE relay, it keeps the fuel pumps running all the time, it does not turn them off, i bought it in a pinch from Napa at the time, the original one had burnt contacts causing a no start which was 5+ years ago. There is also a single pin plug under the dash on the passenger coming out of the ecu loom that is grey with a green stripe and 4 wires bundled together, one of them goes to the ecu, another to the fuel relay, and the other two go under the hood to either the tts or csi. Is this the starter signal connection? When I spliced into my starter wire and connected into this connection the car starts on the csi for a couple of seconds then stalls.
 

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There is also a single pin plug under the dash on the passenger coming out of the ecu loom that is grey with a green stripe and 4 wires bundled together, one of them goes to the ecu, another to the fuel relay, and the other two go under the hood to either the tts or csi. Is this the starter signal connection?
That might be the fuel pump bypass circuit. The bypass circuit bypasses the drive relay to ensure the fuel pumps are powered on when the key is turned to the 'start' position. Then, once the engine starts, the drive relay gets the tachymetric signal via a sense wire on the coil to 'know' the engine is running. The sense wire is either white or yellow (I forget which) and goes inside a braided covering (like a TV cable). The braid is grounded - I assume for protection from stray current so the drive relay won't get fooled.
 

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Discussion Starter #8
Ok, I'm back, sorry about that, been on and off on the car when I got the chance, life and work in between. I've had a couple of theories but I'm still where I was before, ever since I gave the ecu a better ground the noid light stays on while the car is cranking. The injectors are supposed to blink when the car is cranking or running, correct?
I've thought that my main chassis ground was not sufficient enough so I hooked up a pair of jumper cables from my bellhousing to the negative terminal of the battery, but no change.
My next theory is that since I'm using a points Marelli distributor ( i think it's Marelli) is that the capacitor on the distributor is causing the interference with the ecu getting a proper signal.
On an electronic distributor, like the centerline product id405, all it is is a magnet spinning around and turning the switch inside the pickup on and off, is this correct?
And how do I hook it up, red wire to positive + coil and black wire to - side of the coil? Last time I did that and it had magic smoke come out of it.

Do I need a ballast resistor in front of the coil like a 1.5 ohm to dampen the voltage?

Also that shielding that is on the signal wire to the ecu, does that get chassis ground or does it hook up the - side of the coil?
 

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Discussion Starter #10
Hi everyone, so I've grounded the shielding wire with no change, I've checked for fuel pressure before the rail and I'm getting 35 psi on the nose when I've jumped the fuel pump relay. So that got me thinking that if my noid light turns on, the csi is allowing the car to start but not run, maybe just maybe that my injectors were not working. I have taken out the fuel injectors with the rail and gave each one power and ground to see if they would make a click and to see if fuel came out. As it turned out the injectors were all bad, 1 opened somewhat, and the other three shut closed and plugged. I have assumed they were good because I had them cleaned by a reputable company ( and they weren't clean but worse).

The engine now starts, woohoo, but now I have another problem.
The engine will only run if I'm on the gas pedal, if i let go it stalls.

Please bare with me, it seems I'm encountering problem after problem with this car, but I'm determined to finish it.
 

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As it turned out the injectors were all bad, 1 opened somewhat, and the other three shut closed and plugged. I have assumed they were good because I had them cleaned by a reputable company ( and they weren't clean but worse).
That or there is rust or trash in the fuel lines after the filter.
 

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Discussion Starter #12
All the lines are new, the ones coming out of the tank going to the fuel pump under the car, from that pump to the filter, and from the filter to the fuel rail, and also the return line. I forgot to mention that I've bought new injectors from Vicks auto the, the set of 4.

Question, if i clamp off the return line, what kind of pressure should I see?
Maybe a bad fuel pressure regulator or tired pump?
The vehicle is 30+ years old on what I think are original parts.
 

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if i clamp off the return line, what kind of pressure should I see?
1668092

Maybe a bad fuel pressure regulator or tired pump?
A quick-n-easy check for a faulty regulator is to remove the small vacuum hose from the regulator and check for the presence of gas (sniff, taste, etc). If there is evidence of raw gas it is likely the diaphragm has split.
1668093
 

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Discussion Starter #14
Hi everyone,
Update:
I've figured out why my alfa would start and stall on me, it was alot of things at once I've replaced the fuel pump that was underneath the car, and turned out the fuel pressure regulator was ok, then for some reason my intake manifold undid itself or i didn't tighten it down properly( either way it had a massive vacuum leak) then once that was taken care of i have looked at the MAF and it was moving freely. After that the engine was running really rough but running, found another vacuum leak at injector #4, fixed that, after that subtle vacuum leaks here and there.

Now I see that my rpms are jumping between 900 and 1400 rpms so there is no stable idle but the engine does run on its own without my input.

So my new questions to anyone that can answer them ( thank you in advance):
Can a weak spring on the MAF/AFM cause my idle to surge up and down, and can that be adjustable?
For ignition timing i have marked on the crank pulley TDC and as for the other marks like P, F, and M are non existent on my pulley ( weren't there before or after refurbishing the pulley), I'm using a basic timing light with no special features, what am I supposed to set my distributor at, I've read that it's supposed to be 33 degrees, now is that idle or at a specific rpm range.
Thank you in advance
 

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A quick & easy test for intake air or vacuum leaks is to remove the oil fill cap while the engine is idling. This introduces a large air leak (the sump is supposed to be sealed and scavenged by intake vacuum). When you remove the oil fill cap the idle character should deteriorate (due to the air leak). If it does NOT, that means there is likely already an air leak. Happy hunting...

If the spring tension in the AFM has been messed with then, yes, the flap may not ride steady on the air flow. Look at the glue line where the black plastic cover is attached to the AFM. From the factory this glue line will be small & neat. If someone has been fiddling with it, the glue will probably be irregular and excessive.

There is little you need to do for ignition timing. The 'P' mark would have been for TDC. If you have correctly located TDC then just follow the shop manual instructions to aim the distributor. All further timing adjustments are done by the ignition ECU. There is nothing inside the distributor except the rotor - no advance weights or vacuum mechanism. The distributor acts as just a four way switch to send the coil output to the appropriate spark plug. Note that the correct rotor has a wide tip. This allows the ECU to have a fairly wide range for the ignition advance.

The mark you're looking for is on the edge of the distributor body. Remove the cap & the plastic dust shield under the rotor to find the mark.
1670842

1670843
 

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Discussion Starter #16
Hi everyone, it's been some time, okay so i believe i have eliminated most or all of the vacuum leaks, i believe my up and down idle was caused by my throttle body being open too much, so after adjusting the throttle body with the set screw it has a stable idle, i have gotten the vacuum silicone hose set and that has helped alot.

The AFM has been messed with by the previous owner of the car because the square cap has been siliconed on, as to what was done in there i would not know.

Thanks for the post on ignition points and what to look for, but on my car i could not find any of those marks neither on the distributor or crank pulley, probably because of wear and tear and rust eating away the surface. I'm using a mechanical advance distributor with fuel injection, so no ignition ecu, so in terms of degrees what should I set my distributor at, I've read some people saying 30-33-35, is that before TDC at a certain rpm? Or do i adjust it at idle so that it is after TDC? Any and all help appreciated.
 

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Typically, on non-Bosch FI cars, ignition timing is set to the "M" mark on the crankshaft pulley at a specified engine speed. This is maximum advance and the number of degrees BTDC will vary by car and distributor as your research indicates. The short answer to your question is probably somewhere in that range, 30 to 35 degrees BTDC. The important thing is to avoid engine damage from detonation caused by too much maximum advance or an inappropriate advance curve.

To narrow things down, can you provide the distributor you are using? Additionally, you need to find the timing marks on your crankshaft pulley. At least find the "P" mark. If you don't have the timing pointer connected to the bottom of the water pump, then you need to get one or fabricate one and establish TDC.
 

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Discussion Starter #18
Thank you, ok so I've bought the electronic distributor from centerline i think it was id405, when i first used it the pickup failed and magic smoke appeared, so i installed a set of points and a condenser on it and it works. And as for my crank pulley i have no marks on it at all, I've cleaned it up and painted the pulley with a light coat of matt black and i did not see any marks, it was smooth all the way around. And a new one is kinda expensive. I did put the old pointer from my old water pump onto this new one and i have marked TDC on my pulley with a white out brush when I was assembling the engine together.
 

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If you trust your pointer and your "P" mark, then set the max advance to 35 degrees BTDC, per Centerline's tech sheet. Do you have access to an adjustable timing light?

Larry at APE may have a used pulley at a reasonable price.
 
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