1981 fiat spider 2000 fuel injection trouble

[rlux4]

Those two wires going into the head are for temperature senders to the gauge. The temp sensor for the ECU is in the "T" on the front of the engine. Of the sensors for the FI system it is the most critical. Unplug any of the others and it wouldn't make much difference in how the car ran, unplug the coolant sensor in the "T" and if the car ran at all it would be barely. It may be bad, but if you're not getting pulse signal at the injectors, it isn't the problem. You could put a 250-300 ohm resistor in its connector and the ECU would read this as the engine being at normal operating temperature. At this point it's going to be hard to help you diagnose what the problem could be, partly because we don't know what results you've had with the different suggestions so far.
Do you have power on the pink with black stripe wire from the ignition switch to the dual relay with the key on?
Do you have power on the brown with white wire at the dual relay?
Do you have the two wires on the intake plenum good and grounded?
Are the injectors getting a pulse signal?
Is the fuel pump running when the engine cranks? If so, are you getting fuel at the fuel rail?
Is the ignition and valve timing correct?
Let us know the answers to these questions and we can rule out what is working.
Hang in there. When I first got my car it had the intermittent no start or stop all of the sudden problem (one time in the middle of one of our busiest intersections) until I found the problem to be the inline fuse holder. And you're right, after you've got this solved you'll know a lot more about your car than you would otherwise.
Ron

[macawlover70]

Do you have power on the pink wire from the ignition switch to the dual relay with the key on?
Do you have power on the brown with white wire at the dual relay?
Do you have the two wires on the intake plenum good and grounded?
Are the injectors getting a pulse signal?
Is the fuel pump running when the engine cranks? If so, are you getting fuel at the fuel rail?
Is the ignition and valve timing correct?

Thanks ron. Ok,
yes on all three power wires
yes on the grounds to the plenum
No pulse signal
fule pump running and fuel pressure in the rails
ignition timimg and valve ok. I'm just not getting fuel past the injectors. No signal. I have ordered a new relay and it should be here tomorrow. If that's not it I will replace the ecu. If thats not it it's going into the shop. I am going to remove and clean the plenum grounds also just to be safe. Thanks ron.

[pope]

The injectors should have a constant voltage to them, the ECU only adds the ground to activate the injectors.

[rlux4]

Exactly right Pope, hence the need for a noid light. It's really the only thing that I found that will give you a definite indication of pulse as the ground is supplied by the ECU.
Have you checked terminals 88b and 88g on the dual relay. These are power side from the dual relay to the injectors. They get their power from terminal 29 on the ECU through a green wire.
Ron

[racydave]

I think you can hook a simple test light up to posative and check the ground side for pulsating ground. A noid light is best...

[So Cal Mark]

if the injectors aren't pulsing, have you checked the connection to the ignition coil? The ecu has to see a tach signal before it will pulse the injectors

[macawlover70]

Exactly right Pope, hence the need for a noid light. It's really the only thing that I found that will give you a definite indication of pulse as the ground is supplied by the ECU.
Have you checked terminals 88b and 88g on the dual relay. These are power side from the dual relay to the injectors. They get their power from terminal 29 on the ECU through a green wire.
Ron

So I should have constant voltage to the injectors? I don't. That's good to know.
On 88b and 88g I should get a 12v reading? Key on/off?

[Snoopy]

Early this year i had the some thing (no pulse at injectors) and the problem are the grounds to the plenum and the grounds from the engine ...
I cleaned all two times...

[rlux4]

The 88b and 88g should have power when the key is on. BTW, Brad Artigue's diagrams have an adendum page to the FI system that shows these numbers as 88b and 88e. These are probably the ones you have. If you have an 88e, there won't be an 88g.
Ron

[macawlover70]

Ok, I looked at the schematic and it shows one wire from the injector going to the ecu and the other just has a + sign but does not say where it gets the power from. Is the positive to the injectors come from the distributor,ignition, battery, or..................?

[pope]

Injectors get their power from the dual relay. There is a plug in the dual relay that has many white wires coming from it. That is it. The dual relay gets its power from the brown wire in 88z that comes from the battery. I would check to see if you are getting power from the battery through the 10 gauge brown wire.

[macawlover70]

I checked 88b and 88e and I am getting no power to these wires. The relay is new so it is not the relay. What would cause me to not get power to these terminals? I have power to all three wires on the other side of the relay so it is not that either. Help.....

[pope]

When you say that you have power to all three wires on the other side of the relay. There are 5 wires on the other side of the relay. There is a thick brown wire and 4 colored w/black stripe wires. Right?

You have the ignition ON when you say you are not getting power to the injectors, right?

[macawlover70]

"There are three lines of power going to the dual relay. The pink wire from the ignition switch, the 16 ga. brown with white stripe wire coming from the inline fuse, and the 10 ga. brown wire direct from the battery. "
These wires on the other side have power. And no, I am not getting any powere to my injectors. I may be getting the ground pulse from the ecu because when I hooked up the noid light to test the injector signal I got a weak flash one time. may be nothing but that's what i got. So, I am getting power into the relay, getting fuel to my injectors, but no power to them.Also no power to 88b or 88e. I haven't checked for power on any other wire on that side of the relay, the side with all the white wires going to the ecu. I'm about ready to take it into a fuel injector specialist. I'm going to clean all the connctors to the coil and the plenum tomorrow. I need to know where the injector is getting the 12 volt supply from. The ecu? In which case I will replace the ecu, or somewhere else where there may be a bad connection. Help!
Merry Christmas.
Robert

[rlux4]

I just pulled down my dual relay. Terminals 88b and 88e on the dual relay should be sending out constant power when the key is on. You won't see this at the injectors, they will pulse when the ECU completes the ground for the circuit. What I don't understand is, if you have a new dual relay, and power coming to it from all three lines, you should have power going out to the injectors. Whether they pulse is up to the ECU and the grounds on the intake plenum.
Are you checking the two terminals on the dual relay while it's got both connectors plugged in? They need to be, and you put the test light in where the wires exit.
Ron