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Discussion Starter #1
Hello Fellow members


I have an 86 alfa s3. The car runs smooth after its warm, but during cold start up,its hard to start. I havento pump the pedal sveral time for it to finally start. I know this isnt a carb emgine and pumping the pedal should mot do anything but it is. As per the jtronic diag. I have checked my fuel pressure-good, the CTS and TTS-good, has a new TPS, New AAV, new injectors. I noticed the afm has been messed with before so I started to dive into it to. I noticed by turning the well the idle can be adjusted. Now i know these never fail and are calibrated by a special machine. Do you think my afm has been messed with so much that its bad now?
 

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Have you actually pulled the cold start injector and see if it sprays fuel when your starting it cold.
 

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If it runs well once it starts I'd put the AFM low on the list of suspects.

Measure system voltage during cranking. It can sound like it is cranking over with vigor but if system voltage drops below ~ 10.5V the computers won't send the make spark/squirt fuel signals. Don't do this by looking a dash gauge (if your car has one) as they don't usually read properly during cranking. Connect a voltmeter to the battery and note what it reads. With everything off a good battery should show 12.6V. Then see what it reads during cranking. (Our '84 Spider reads ~ 11.6V - 11.8V during cranking.)

If the above test shows marginal results, try cleaning all connection in the battery to starter circuit, charge up the battery and re-test. If it is still marginal consider a new battery.
 

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Discussion Starter #5
The battery stays on a trickle charge and the voltage is all good. So im ruling that out. And let me clarify it runs ok lol the idle is semi smooth.

***update***

Ok when I first start it after its cold the engine catches and wants to start for a second then shuts off. Then it takes several tries with me pumping the accelerator then it starts.
 

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As you know, pumping the pedal does nothing for an EFI engine. What happens if you don't touch the pedal? What is the idle speed for the first 30-90 seconds after starting a cold engine? What is the idle speed when the engine is warm?

With a properly functioning AAV, the cold idle speed should be ~ 1100 - 1300 rpm & the warm idle 900 - 950 rpm. (have you checked if your tach is reading right?) The AAV should be closing within a minute or three (depending on how cold it is) with the resulting change from cold idle speed to warm idle speed. If the idle is too slow &/or the AAV isn't opening when cold & closing when warm that might explain the symptoms.
 

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Discussion Starter #7
If i dont pump the gas pedal it just ctanks and cranks and cranks and nothing will happen. I think with opening the throttle plate (pumping the gas pedal)the car gets more air into the system, am I wrong? The tach does bounce but its set around 1100 rpms when cold. Maybe I could get a rpm reader from the autostore to see what the rpms really are
 
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