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Suddenly dying at 2000 rpm


Chuck

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Like the old saying goes... 90% of electrical problems are carburetion.

 

Maybe you could test running the engine with oil temperature sensor disconnected. See if it behaves differently when it thinks it's cold all the time. At least rule that out.

 

My Greenie had a problem with sputtering (not total shut-down) after giving it some gas. It started and idled easily. Turned out that the inlet to the fuel pump was partially blocked. It allowed enough fuel to pass for low RPM running, but not enough for faster.

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I've had this exact problem, cutting out at 2500rpm, or if the throttle was WO at that point, coughing and backfiring for a bit and then cutting out. Described in http://www.v11lemans.com/forums/index.php?showtopic=19943&do=findComment&comment=220789

In the end, it was a too thick o-ring underneath the timing sensor, it was extruded underneath the mounting plate, pushing it away from the engine block. Heat of the engine would cause it to expand a little more, making the gap of the sensor just slightly bigger, causing it to lose readings above say 2500rpm...

 

My guess here is timing sensor.

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I won't bore you with all the details.. :) but the DSM (Distinguished Stupid Mechanic) put the o ring on the wrong side of the shims. What *was* he thinkin?? That adds .060" to the normal .030" gap, and the magnet loses it's ju ju as the missing tooth on the phonic wheel goes faster and faster. ECU says, "What did you say?" Better play it safe and shut down.

It wasn't all for nought, though. I learned how to check everything at the ECU using KR's excellent pdf, and how to make sure the relays were working normally, courtesy of KR, too. Thank you, sir. Doing all that got it to the point where it *had* to be the timing sensor. I also have a much better understanding of how all this stuff works.. always a good thing. :rasta:

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Pretty sure I did something similar last winter. Glad you got it.

I think you were the first correct answer..

 

 

Would checking the resistance of the coil tell you if the sensor is reading correct? Like if the gap is incorrect.
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Pretty sure I did something similar last winter. Glad you got it.

I think you were the first correct answer..

Would checking the resistance of the coil tell you if the sensor is reading correct? Like if the gap is incorrect.

No the resistance will just tell you if it’s shorted or open.

The sensors are very simple, just a coil of wire wound over a small magnet, as the teeth of the wheel pass it creates a ripple in the magnetic field generating an AC signal in the coil.

I measure the gap by sticking a blob of JBQuick on the tip of the sensor, bolt it in until set then take it out and measure, it won’t stick to the oily phonic wheel.

 

Don't pay $200 for the part when it breaks I suggest you have one on hand from the source Antmanbee gave me.

http://www.miparts.com/detail/rpm-sensor-engine-management_15598#.WsC7rSMZNBz

http://www.v11lemans.com/forums/index.php?showtopic=19514&page=2

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My '97 Sport i came to me with intermittent intermittency. 
On the way to a complete and sudden failure, the timing sensor symptoms were hard starting, spluttery and unsteady running, similar symptoms to lean conditions; this evolved (over the course of 100 miles or so) into quitting altogether when hot. Related to your symptoms, somewhere along the way it did begin to cut out at about 2500 or so, as if it was running out of fuel. At the end of the day, when it was cold it mostly worked but when hot went open-circuit. (I verified the resistance at temps but don't have them recorded) 
So, they don't necessarily fail all at once.

As for their function- and I'm not trying to start an argument- a simple coil generator like this actually makes more voltage as the reluctor passes faster, so theoretically if reluctor gap is the issue, it should show up at lower RPMs. I would suggest that a shorted or part-open coil will have an unsteady field, confusing the computer which wants to see a steady sine wave. 

I found the cam sensor on ebay from Europe for $18 plus about the same in shipping; they used this same sensor on about every fiat and other brand in the world, but they never came to the US so we have no source for them here. 

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