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1989 Quad...
New plugs, wires, injectors, all hoses are correct, new fuel pumps. If I give it a squirt of starting fluid it starts and runs/idles...OK. If I depress the accelerator quickly, it will bog down and stall.
Is there a valve and/or sensor that is not possibly functioning correctly?
What am I missing.
Thanks in advance for any insights!
 

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1984 Spider Veloce
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1989 Quad...
New plugs, wires, injectors, all hoses are correct, new fuel pumps. If I give it a squirt of starting fluid it starts and runs/idles...OK. If I depress the accelerator quickly, it will bog down and stall.
Is there a valve and/or sensor that is not possibly functioning correctly?
What am I missing.
Thanks in advance for any insights!
My guess would be a post MAF intake leak.
 

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Won't start cold or warm? The Cold Start System (CSS) is stand alone - not under computer control. The CSS consists of the Cold Start Injector (CSI) & Thermo Time Switch (TTS). The TTS sends power to the CSI depending depending on the coolant temperature. The colder it is the longer it'll tell to the CSI to squirt. When the engine is warm, it won't tell the CSI to squirt at all, when very cold it might squirt for 10-20 seconds. Another component is the Auxillary Air Valve (AAV). When cold the AAV should be nearly wide open. This increases the cold idle speed. As the engine warms up the AAV closes to return the idle speed to normal. The AAV is also not under computer control. It is common for the AAV to fail in the partially open position thus it neither increases the idle speed nor allows it to return to normal.

Click on the link in my signature for a page of DIY diagnosis info about the L-jetronic system in our cars. You may need to click the down arrow to see the whole signature.
 

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Low fuel pressure due to failing pump, clogged filter, malfunctioning pressure regulator? There should be a place where it is easy to connect a pressure gauge, maybe the hose to the cold start valve.
Check out the L-Jet troubleshooting procedure that is here: L-Jetronic Technical Info - Alfa Romeo Spider
 

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Another thought. The fuel pumps are powered on only under two conditions: 1) the engine is running or B) the key is turned to the 'start' position. The fuel pumps get powered through the drive relay. The drive relay gets a tachymetric signal via sense wire at the coil to "know" the engine is running. To ensure the fuel pumps get power while starting there is a bypass circuit that bypasses the drive relay when the key is in the start position. Note that the fuel pumps do not get powered up KOEO (Key On, Engine Off)

So, my thought is that maybe the bypass circuit is faulty. For a quick test try this; cycle the key on/off, on/off. on/off. Then try starting the engine. Each time the key is turned to 'on' the drive relay will interpret that brief surge of electrons as the beginning of the tachymetric signal and it will briefly power up the fuel pumps. A few quick on/off cycles will thus build up some fuel pressure and perhaps allow the engine to get started.
 

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I had a car (87 Grad) run like that. It would start and idle, but under any load, the plugged cat would cause enough backpressure to shut things down.
Been there also but on a Datsun.
 

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Discussion Starter #12
50% new, the other half? Who knows!
I’ll get it drained and completely replace in the morning...dah! Thanks for the tap on the shoulder. I’ll replace the filter, again, as well!
 

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Discussion Starter #13
Still searching to find the culprit that does not allow the car to start without ether. Hopefully I’ll “stumble” across the problem and be able to post a chronological path to a solution...someday. I’ve been spending 3-4 hours a day looking for a remedy prior to throwing another $500+ At replacement parts whatever they may be...frustrated? Yes...
 

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It’s Bosch fuel injection, every part can be tested. No need to blow money. Find the part that tests poorly then go from there.
 

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I have no idea where to test, what values are to be displayed.
Well, in post 6 of this thread, Eric let you know about the link in his signature that is basically a custom guide to troubleshoot the Bosch injection on 82-89 alfa spiders. For convenience I will post a direct link here,


I've also had good luck myself following this document when troubleshooting L-jet (the version of Bosch fuel injection you have). I found this one more step by step but it's not specifically for alfa, though all the components are the same and have the same names.

It seems you can rule out spark issues since it will run on starter fluid. Ruling out ignition problems is always the first step in fixing a fuel injection problem.

Cheers,
 

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Discussion Starter #19
Well... still trying to figure out this “cold starting” problem. I’ve replaced pumps, hoses, filters & injectors.
All that’s left as far as I can tell is the cold start injector and valve...
I’ll hopefully post a positive result soon.
Frustrated!
 
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