'81 Spider 2000 will not stay idling. please help!!!

[LincolnYoung53]

I have an '81 Fiat spider 2000 thats fuel injected that I recently acquired. It wouldn't start so my buddy and I tried some troubleshooting. We finally got it to start after taking the intake off of the throttle body and spraying in some ether as we cranked the starter and got it running. But as soon as the ether runs out the engine died. We tried it a few times and as its about to die we'd add more ether and it would keep running til the ether is all spent. He told me that most likely it had to be a fuel delivery problem. We checked the fuel lines and there was fuel in the lines and rail. So next we checked the voltage on one of the injectors and it had power running through it.
-- please help! What other steps can I take? He said it might be the ECU faulting and not pushing enough power to open up the injectors to allow it to open to deliver the fuel.
-- The person I bought it from said it was his daily driver and he left it sitting for a few months while he went away for school, when he came back this summer it started to "lurch" on him.
--I'm a first time Fiat owner, any help would be greatly appreciated!

[76was124]

The first 5 seconds (give or take) of idle is from the Cold Start injector. The csi is located on the front of the intake manifold and has a blue plastic body where the hose from the fuel rail connects. It is controlled by the thermal time switch. Make sure that circuit is working and the csi is delivering fuel.

Be careful removing the fuel hose from the csi as its a plastic connection and likely brittle at its age. There are lots of threads on this topic as well as a great FI tune up/ troubleshooting guide you can download written by Brad Artigue.
http://www.artigue.com/fiat/

Also, anytime removing fi hoses or related parts, be sure release the fuel line pressure first ( how to is documented in service manuals).

[FiatMac]

We finally got it to start after taking the intake off of the throttle body and spraying in some ether as we cranked the starter and got it running. But as soon as the ether runs out the engine died. We tried it a few times and as its about to die we'd add more ether and it would keep running til the ether is all spent.

The car will not run with the intake hose disconnected. Air must pass through the air flow meter in order for the fuel injection computer to know how much fuel to inject. With the intake hose disconnected the flap on the air flow meter stays closed indicating to the computer that there is no air flow so no fuel will be injected. The engine runs until the ether is consumed.

Also the fuel pump will not run until air flow is sensed.

[azruss]

Inspect the rubber plenum for any cracks or air leaks. It must be air tight from end to end.

[Lkcast]

i had the same problem and changed both fuel filter and fuel pump and now runs fine.

[RRoller123]

Check that the flap inside the Air Flow Meter (boxy device at the beginning of the long air tube) is swinging freely. It must be to allow the car to run. It sends the air flow data to the ECU. Make sure the connector to the side of it is well seated. With the key on but the with starter not yet engaged, do you hear the fuel pump running? This is an indication that the fuel pump was hard wired in. Normally it only runs when the flap on the AFM door is open. You can test this by disconnecting the air hose, putting the key in the on but not starter engaged position, and manually moving the flap door. The fuel pump should then come on.

[bradartigue]

He said it might be the ECU faulting and not pushing enough power to open up the injectors to allow it to open to deliver the fuel.

Your friend is giving the ECU too much credit, it's not that smart. If you have power to the injectors but the car won't run then you probably don't have power to the fuel pump. The fuel pump runs when air is passing through the air flow meter. All of the hoses must be installed and it cannot leak anywhere in the system.

Follow a diagnostic guide, I have one http://www.artigue.com/fiat or you can find them all over the web; L-Jetronic is common as dirt and diagnosing requires patience and a multimeter (not a voltmeter that doesn't have a battery, a multimeter that selects continuity, resistance, voltage, etc.)

Nothing will make you happier then getting your own old car to run - but stop spraying ether or starter stuff into your plenum, you'll burn something up like a valve. We know it isn't delivering fuel, figure out why.

Report back new owner, and welcome to the joy.

[RRoller123]

A very inexpensive mechanic's stethoscope from HF will allow you to hear the injectors clicking, very clearly. Wonderful little tool. Let's you isolate which valve might be making the noises we always hear too. Stuff like that.