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Discussion Starter #1
Thanks for the help guys I replaced the flywheel sensor and when I turn the key it runs great for about 3 seconds and then shuts off! Any suggestions where to look now, electrical or fuel. By the way I replaced the gray flywheel sensor
 

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It sounds like mabe your cold start injector is activating but the the mains aren't kicking in, or at least staying on steady.

Presumably you've been to the page linked in my sig (ghnl's L-jet page) so you can find stuff a bit easier now.

For starters I'd be checking the AFM connection, the fuse back by the ECU (replace it whether it looks good or not) both relays back by the ECU (see if the small one kicks on and if not, does the big one send it a 12V signal on the smalls #86 terminal while cranking and if not, then check wiring at the coil and big relay).
 

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My guess is that your Spider is starting on the fuel from the CSI (Cold Start Injector). The CSI will squirt fuel for 3-5 seconds then quit. The fact it does run for those few seconds would seem to indicate the ignition system is functioning.

If that is true, we need to figure out why the main fuel injectors are not squirting.

Try this: remove the 'parcel shelf' (horizontal carpeted panel behind the seats). Check all the electrical connections and especially the drive relay's and the FI ECU (ECU = "computer"). When you start the engine tap the drive relay (use the handle of a screwdriver to give it a few 'boinks'). My thinking is that maybe the drive relay is sticking. The drive relay waits for a signal from the coil that ignition is happening then it sends the signal to squirt fuel. If it's stuck sometimes tapping them will shake them into action.
 

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To keep replies together, I copied your post from there to here.

Hey, thanks for the help again guys. When I turn the key to the 2 position I can hear both relays turn on, and on the smaller relay I get a reading of 12 volts. So I think both of my relays are working. Now I was wondering if the car should be pumping gas when the key is in the number 2 position because mine is pumping very little. And when it is in the number 3 three position it pumps a lot of gas.
When you first turn the key to 'on' the drive relay will briefly send power to the pumps. Then the drive relay stops powering the pumps until it 'sees' that the ignition system is firing. So, we need to confirm that you really have spark. No spark = no signal to drive relay = no fuel injection. It'll run for a few seconds on the fuel from the CSI (Cold Start Injector) because the CSI is not under the ECU's (computer's) control. The fact it runs for those few seconds would seem to indicate a functioning ignition system. But it'd help to confirm the presence of spark.

Use a spare spark plug, Connect the threaded part to ground (the engine block/head) and put a spark plug wire (any one will do) on that plug. Now crank the engine (or get a helper to do so) and watch for a nice consistant spark.

Did you try the 'whack the relay' suggestion? And there are two flywheel sensors. Did you test them both? Are you certain the connectors are plugged in to the correct positions? One is for timing & the other is for RPM's - the sensors are identical but they have to be connected to the ECU's harness correctly.

Have you run through the L-jet diagnosis page's many suggestions? Replacing fuses (even if the look OK? Cleaning and tightening all grounds? Ensuring there are no intake air leaks? The L-jet is a system. All items have to be functioning correctly for it to work.
 

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Question

If whacking the relay works to get the car running, what is the permanent fix? Do you simply replace the relay?
Arden
IF clean connections in that particular relay box = still not working THAN
replace relay
 

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How much gas is in the tank? This happened to me and what it ended up being was the house in the tabnk was split. A friend suggested I fill the tank all the way up and the car ran. I replaced the hose and everything is great!

Publio
 

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Discussion Starter #10
How do I check my relays?

Hey I checked the sparkplugs and got a good spark. I was wondering if there is a way to check the relay and if there isn't a way to, where can I get a new one? I checked IAP and they didn't have one anywhere else?
 

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You are, in all likelihood, getting positive fuel pressure, or the CSI wouldn't keep the engine running....in fact it probably wouldn't run at all. To put your mind at ease, try turning the ignition switch to "on" (not "start"). You should hear the relays click and the pump run momentarily.

Try measuring voltage at one of the fuel injector connectors while starting/running to see if it's getting juice (if you only have a digital voltmeter, hook up a test light instead....the pulse of the FI signal doesn't exactly give positive voltmeter readings).
 

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Discussion Starter #12
Still not running!

Can I test the main relay? So far I've replaced the gray flywheel sensor (the other one tested good), replaced the drive relay (after whacking it first and it didn't do any good), the relays click when the key is in the number 1 position and I hear the fuel pump run for a second. I also pulled the spark plug and it has a strong spark when cranking. We filled the gas tank too and also new plugs, wires, cap & rotor. After doing all these things she still does the same thing - turns over and runs for 2 to 3 seconds, then turns off. I am frustrated
 

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Well, I'm stumped.

Just to be certain, check the ignition timing (although I doubt it'd run for the 3 seconds if it was off...) Position the #1 piston at TDC on compression (remove the spark plug and note when air is forced out the spark plug hole then position the piston at its highest &/or when the 'P' mark on the pulley aligns with the pointer on the lower, left side of the water pump). Remove the distributor cap first making note of where the #1 plug wire connects. The rotor should be aimed at that part of the distributor. Actually if it was installed correctly, the rotor should be aimed at a small notch in the distrubutor's body (under the plastic dust shield below the rotor). It is not unusual for the distributor to be 180 degrees off. The engine will (can...) run fine as long the plug wires are re-arranged for their new positions. Once you confirm that the rotor is really aimed at #1 check firing order: 1-3-4-2 to ensure the other 3 cylinders are being told to spark at the right time.

Also, make certain the harness connectors are plugged into the flywheel sensors correctly. The sensors are identical but they have to be connected to the harness in the correct way - black connects to the upper sensor, grey to the lower. If they are swapped timing will be off (even though the sensors test OK).

You can try switching the ignition switch on-off-on-off to pressurize the fuel rail then apply 12V to the injector terminals while watching for injector squirt past an open intake valve via the spark plug hole. Remove all the spark plugs and you can see (via the spark plug hole) when an intake valve is open. Unplug that injector's harness connector and briefly apply 12V to the injector's terminals while watching for fuel to be sprayed past the open intake valve. After 2-4 brief touches of the 12V's the fuel pressure will drop enough that it'll cease squirting. But that'd at least prove that they can squirt.

Beyond that, there must either be a fault in the signal getting to the injectors, faulty injectors, or a faulty ECU. My research indicates that the FI ECU is quite sturdy so that'd be the least likely problem (we can hope...).
 

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Can I test the main relay?
Here's a snip from the injection wire diagram. Maybe it'll help?

Check the coil signal wire. IIRC it is a white wire inside a braided wrap inside a black outer covering. It looks like it attaches to the drive relay at terminal '31b'. Without a valid signal from the coil, no fuel injection...
 

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Does tapping the gas make any difference?

Kinda shooting in the dark here, but have you checked the function of the aux air valve, and also the throttle position switch (AAV can really mess things up)? Also, have you replaced the hoses?
 

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High fuel pressure??

My '83 is now doing what lilspydr describes after correcting fuel delivery problems. Quite a head scratcher..I have hooked up a fuel pressure gauge T'd off the line to the fuel rail. When it will run for a few seconds, I get around 34 +/- psi and at that level all seems cool. ( Keep in mind, I have cleaned all lines, new filter, 1 new pump & double verified return line is clean.) I can watch gauge & then all of the sudden pressure will rise to 40-42 and it dies.

Other times I get the 3 second run syndrome only and pressure never goes below 40 psi.

The manual says too low or high pressure will cause that (3 second die). I am thinking mine is due to too high pressure in fuel rail by regulator not bleeding pressure off as it should. To test regulator, Manual says to disconnect vaccume hose from top of regulator? Seems odd, why disconnect? It does not say if you should plug the line to intake or not. I have tried both ways and pressure remains 40+. Would the regulator then be bad and could that be lilspydr's issue too?

I am thinking of bucking up for a pressure regulator.

Thoughts of the "board"?? Thanks, Matt A.
 

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my guess: pressure regulator is dead.
initial pressurizing to 34 and since pressure reg do not let excess to flow out, pressure buildup kill the pump?
 

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When it will run for a few seconds, I get around 34 +/- psi and at that level all seems cool. ( Keep in mind, I have cleaned all lines, new filter, 1 new pump & double verified return line is clean.) I can watch gauge & then all of the sudden pressure will rise to 40-42 and it dies.

Other times I get the 3 second run syndrome only and pressure never goes below 40 psi.
I'll bet that means something. Danged if I know what, though...

Anyway, attached is a snip from my copy of the Alfa Shop Manual re: testing fuel pressure regulator.
 

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Discussion Starter #19
Thanks for all your great help guys. But I am still needing to finish checking the electrical parts before moving on to the fuel system. I wanted to replace both the main and drive relays. International Auto Parts (IAP) only has the drive relay. They said that they don't carry the main relay and if they don't carry it, you don't need it. So I replaced just the drive relay (the large one). The last schematic that ghnl sent was great. It looks like electricity goes through the main relay so what if the main relay IS the problem? Should I be trying to find a new main relay even though IAP says I don't need it? Another thing, in the troubleshooting guide on page 00-33 the number one thing to do is replace the relay sets. That sounds like both to me. Then, on page 00-46 of the troubleshooting guide I am told to check the start valve for leaks. I pinched off the fuel line using a clamper and the engine would not start, which seems logical but then it says "replace start valve". Shouldn't the engine NOT START if I am clamping off the fuel line? I don't get that at all. Thank you for your time.
 

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If the pump comes on at all then your drive relay is definitely good and I'm 99% sure the main relay is also good. And since you hear the pump run when the key first goes to the "on" position, that indicates the signal lead from the coil to the relay is good too. Methinks your problem lies elsewhere.............
 
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