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95 LS 5 speed 45,000 miles, the car is driven rarely (not a good thing) About two weeks ago started to miss on start up the problem seemed to go after few miles of driving hard , the engine light would come on and then would go off, the next day would do the same thing until finally would not start. It is cranking I smell fuel but no spark, the battery died before I can get the codes. The car is a good distance from any Alfa mechanic or any mechanic for that matter; I have owned several Alfas and been lucky that I never had a single problem with any of them (good maintenance).
I checked the usual things fuses ,relays ,wires ,connections ,charged the battery everything seems ok , I suspect either the cam sensor or the crankshaft sensor ,I pulled the cam sensor and measured the resistance and it reads 427 ohms the manual say it should be 20 ohms, my question is; would a defective cam sensor cause a no start?
I would appreciate any help .
Thanks
C.
 

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I am wondering if you have a fuel starvation problem? Have you ever had the fuel pump out of the tank to replace the factory hose that rots out? If not this is where I would start looking. Just my suggestion.
 

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Be sure to check the ignition module connections (modules are mounted on the inside of the left fender well behind the driver's side of the radiator end tank below and behind the lhs headlights) as these will sometimes lose their conductivity due to becoming loose, getting really dirty, water, etc. For these LS's, all electrical connections in the engine compartment must be taken apart, cleaned with electrical spray, and then reconnected using lots of dialectric grease. This should be the first thing you do when trouble shooting, as it is easy and cheap.

I had this problem with my LS, and solved it by doing the above, esp the ignition module plugins on the bottom. These connections are in a very vulnerable position for getting dirt and water in them, and being close to the engine, eventually working loose.
 

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Fuel Smell

You should not have a fuel smell. Check the rubber fuel rail hoses and see if they are leaking badly. As Del says, check the ignition module connections under the air box. Check the temp sender connections (the one that is on the thermostat housing but hidden under the hose)- if this is goofy car can run very very rich (fuel smell again)

Is this fuel smell 'new' to the problem-- in other words, did the fuel smell show up about the same time the misfire and poor running did??
Oh yeas, the fuel pump gets its signal off the crank sensor IIRC. I had an intermittent no start on the 139K LS. It was intermittent for 3 years -- sometimes no prob, other times no start. Turned out to be the fuel pump (at least thats what we think-- changed it and so far so good **fingers crossed***). Didnt produce a fuel smell though
goats
 

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Discussion Starter #5
What I meant by fuel smell is that the engine is getting fuel, the plugs are wet , never had a problem related to fuel, I checked the connections on the ignition modules ,they looked fine ,my question still would the car run if the cam sensor or the crankshaft sensor is defective?
 

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I pulled the cam sensor and measured the resistance and it reads 427 ohms the manual say it should be 20 ohms, my question is; would a defective cam sensor cause a no start?
A few people have also gotten ~500 ohms for the cam sensor, so you can ignore the 20 ohms from the manual. IMO, a defective cam sensor would not cause a no start. That cam sensor is used in conjunction with the knock sensors to detect engine knocks. If the ECU detects bad signal from the cam and knock sensors, the car should just run in a more conservative mode.

When you say smell fuel, is it from the engine bay or from the tail pipe. If it is from the tail pipe then you are just throwing too much fuel (from cranking) into the exhaust. It will make things worst by fouling the spark plugs futher and eventually the fuel might ignite/burn in the exhaust. Try to troubleshoot with minimum cranking.

You mention it seems to have no spark. The ignition modules, temp sensor (for Motronic), TPS and other electrical connectors are a good places to start. Check/clean the big round electrical connector close to the oil filler cap and the ground wire below it (from what I recall).
 

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What I meant by fuel smell is that the engine is getting fuel, the plugs are wet , never had a problem related to fuel, I checked the connections on the ignition modules ,they looked fine ,my question still would the car run if the cam sensor or the crankshaft sensor is defective?
If the ECU is not getting the crankshaft sensor signal, the fuel pump would not keep on running. So, do you think the fuel pump runs and you are getting reasonable fuel pressure?
 

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temp sensor

check it . IS it possible that you (I hate to say it......) slipped the tbelt?
 
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