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Discussion Starter · #21 ·
Jim,

I've had two GTV6's with this exact same problem so I feel your pain. I called my friend who is an Alfa mechanic and he told me it could be a couple different things. On one of my cars, it was the oxygen sensor wires on the passenger side of the firewall that were rubbing on something and shorting out. On the other, it was the 6 prong? modular box that hangs upside down by the steering column. It has a fat green wire going to it. If your car has had rust issues around the windshield, water can get in here and cause some havoc.

Check these two things out and hopefully you'll find the issue. I'm no mechanic, but I hope that helps.

Marco
Marco,
I just put on a new exhaust which included a new O2 mount, AND I have a hole at the base of both A pillars. I'll check them out. Again the thing that I cant understand is the three lap delay before it acts up. Maybe a red haring that is coincidence.
 

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If it's the wire at the base of the distributor it would cause a no-spark situation, the tach would drop, same with the box near the steering wheel, so it won't be one of those...

Although that connection at the distributor is very shady and certainly warrants a good careful look. There's two wires (the green one is a coaxial wire) going into one plug and its very easy for the two to start touching.
 

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Such behavior has been tracked to poor electrical connections. Cable/harness stresses from turns have opened up marginal pin contacts on not-quite-there connectors. Check out your cabling, including at the ECU. As this is an LJet (no?), you might consider the crank sensor as one possible offender. You might consider also putting a fuel pressure gauge on and seeing whether it is the fuel pump that is shutting down, or just the ignition. Or something else. Hope this helps.

Michael

edit: I think the GTV6 uses the AFM flap signal to enable fuel pump. your crank sensor connection might open up and fail ignition, but the AFM will still be sucking air and the fuel pump won't shut off. But the injector pulses might stop even though the fuel pump is running.
 

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I had a hallamp go that would do strangs things like this.(the thing under the coil)
mine would cut out with I pulled on the connector but the fault was the part not the connector.
A run to the junk yard got me a working one. off a BMW or VW and may more use the same thing
 

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This sounds like an elecrical problem, i had this problem on my gtv6 turned out to be the ignition switch wires. They started to melt the black plastic socket they were connected to and the car would go completely dead. Have a look there.Good luck.
 

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??? It's cutting out abruptly, seems like either of those would be great candidates.

bs
Yes but the tach would drop, and he says it doesn't... wouldn't hurt checking though :)
 

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how does the tach not drop if the engine cuts, if the tach is showing engine rpm?
 

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Yes. Get under the dash (or reach under there) while the engine is running and wiggle things. If the engine cuts out, you've found the crucial area. Focusing in on the details is all that is left. I found a problem like this in my fuse block that was keeping the left turn signal from working all the time. After I noticed that the blinker would work after a _very_ hard left turn, I started kicking the harness above the driver's footwell until it started working again. Later, I fished around and found a very iffy fuse block connection that I repaired. All is now well.
 

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The tach gets its signal from the low voltage side of the coil. Did the tach die with the engine or did it indicate rpm after the engine had lost power? That should narrow it down. If the tach was running then it is probably either the ecu or the fuel pump that shut down. You can hot wire the fuel pump straight from the ignition switch. If the problem goes away then there is something in the combo relay/AFM switch circuits. The coolant sensor that feeds the ecu will stop the engine if the circuit opens.

Divide and conquer - the key to troubleshooting.

Ed Prytherch,
79 Spider
88 Verde
 

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Well the engine doesn't fall to 0 rpm immediately, right? it'd slowly dwindle down... if anything happens to the ignition system the tach drops to 0 instantly, like in a fraction of a second, boom, tach=0, while the engine is still turning, since the tach is connected to the ignition. If the tach follows the engine going down, it's highly unlikely that it is the ignition.
 

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Yuh, trust me, I've seen this happen a little too often in the past few weeks.. :(
 

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Discussion Starter · #35 ·
Thanks for all the suggestions. The first thing I checked was the fuel pump connections. All were ok, I then pulled the inertial switch under the hood and the pump did shut off but the engine dies a slow death as the fuel pressure in the rail drops. On the track the engine would cut out instantly and come back on just as quick after exiting the turn. While in the turn, I kicked the fues box in frustration and no change. I did not notice if the tach died or not. I also considered a short in the sterring column. Wiggling the key in the turn made no difference and turning the wheel to the right while in the pits did nothing. Asle driving the car on the street though rt and left turns including off ramps failed to trigger the shut down. It is only with heavr lateral G loads, 2 to thee laps worth before the gremlin appears. I am discounting the time element because I can't imagine any component that is sensitive to latertal loads and time and/or temperature. Will go over the wiring in the next week and plan on autocrossing the car in the comming weeks. Hope to sort it out.
Jim
 

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Discussion Starter · #36 ·
Some clarification is needed. I do not recall if the tach dropped to 0. I was too busy watching my mirrors as to not hold someone up. And the steam coming out of my ears was fogging up my helmet!! I did wiggle the key and turned the wheel back and forth a little thinking it might be in the sterring column but it did not help. I also kicked the fues box in frustration.
If the tach does not drop to 0, only drops with decreasing engine RPM, would it be safe to assume I'm loosing power to the injectors?
 

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Some clarification is needed. I do not recall if the tach dropped to 0. I was too busy watching my mirrors as to not hold someone up. And the steam coming out of my ears was fogging up my helmet!! I did wiggle the key and turned the wheel back and forth a little thinking it might be in the sterring column but it did not help. I also kicked the fues box in frustration.
If the tach does not drop to 0, only drops with decreasing engine RPM, would it be safe to assume I'm loosing power to the injectors?
In my opinion, it makes it even more likely that the problem is in the wiring around the distributor, or combo relay..

bs
 

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In my opinion, it makes it even more likely that the problem is in the wiring around the distributor, or combo relay..
bs
Why?
This is the ignition system... which controls the tach... so if combo relay, distributor wire, ignition module or ignition ECU controller go south the tach drops. I'm not sure if that's also the case for the coil, as it sits after the tach wiring.
 

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Why?
This is the ignition system... which controls the tach... so if combo relay, distributor wire, ignition module or ignition ECU controller go south the tach drops. I'm not sure if that's also the case for the coil, as it sits after the tach wiring.
Engine is dying suddenly during right hand turns. Personally, I'd forget what's going on with the tach when it happens, I'll wager the driver wasn't paying enough attention to the tach for it to be a factor in the diagnostics.

In my experience, when an engine dies abruptly, it's electronics, not fuel. And when an engine dies during turns, the most likely electrical cause is some kind of stress on a wire that would be affected by whichever direction the engine would be stressing it. In this case, a right hand turn, the engine is leaning toward the left, stressing the wires on the right side of the engine.

Until I'd eliminated them, I wouldn't spend a lot of time looking elsewhere.

And it should be pretty easy to eliminate them, they're all pretty easy to get to.

Just looking at the most obvious behavior first, and based on what I've heard, it's the right hand turns.

bs
 

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Discussion Starter · #40 ·
Engine is dying suddenly during right hand turns. Personally, I'd forget what's going on with the tach when it happens, I'll wager the driver wasn't paying enough attention to the tach for it to be a factor in the diagnostics.

In my experience, when an engine dies abruptly, it's electronics, not fuel. And when an engine dies during turns, the most likely electrical cause is some kind of stress on a wire that would be affected by whichever direction the engine would be stressing it. In this case, a right hand turn, the engine is leaning toward the left, stressing the wires on the right side of the engine.

Until I'd eliminated them, I wouldn't spend a lot of time looking elsewhere.

And it should be pretty easy to eliminate them, they're all pretty easy to get to.

Just looking at the most obvious behavior first, and based on what I've heard, it's the right hand turns.

bs

While at the track, I inspected the plug a the base of the distributor, plug to AFM, grounds to valve covers, and all the wires on the pasengers firewall. One wire was loose in the two white plugs, fixed the spade connector but the problem persisted. My trackside inspection consisted of jiggiling the wires and plugs while the engine was running, not very scientific, but the best I could do in 95 degree heat. I plan on revisiting all these and also the spark box and ECU. I doubt I'll get a "gotcha" momment, and find the problem, I just hope it will be solved and assume I cleaned the offending connection.

Jim

PS My guess is I'm loosing juice to the injectors or the whole harness. If I was loosing just spark while the injectors continued to function, I would expect a backfire when all that raw fuel got ignited upon refiring.
 
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