Engine wants to die when put into gear

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jlwhitney35
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Re: Engine wants to die when put into gear

Post by jlwhitney35 » Thu Jun 06, 2019 7:56 pm

OK, found the "high idle system".

2 hoses, one is from the carb and the other from the intake manifold.

To solve the issue:
1. I'll disconnect the hose from the carb and cap that port.
2. I'll disconnect the hose from the intake manifold and cap that port.
3. I'll disconnect the 2 wires that connect to the high idle unit itself.

Does this sound reasonable before I do this?

Thank You
Jeff
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bartigue
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Re: Engine wants to die when put into gear

Post by bartigue » Fri Jun 07, 2019 4:59 am

Yes that’ll do it. Though I fear sending you down a rathole. Remove the thing because it really has no value, but I’m curious is the engine dying and the clutch is still engaged?
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Brad Artigue
1969, 1969, 1970, 1979, 1980, 1981, 1982, and 1982 124 Spiders
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friedman
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Re: Engine wants to die when put into gear

Post by friedman » Fri Jun 07, 2019 7:43 am

The symptom I'm talking about is rpm drop or engine dying at idle by merely engaging the clutch, still in neutral, no shifting of gears.
I mention this as I recently had a problem with my X1/9 showing these symptoms when engaging the clutch and it turned out to be the crank thrust bearings having fallen out of place and allowing the clutch engagement to push the crank shaft enough axially to try to kill the motor. Easy enough to check by prying on the crank pulley to see if there is so much play that you can see or feel the crankshaft move axially.

Hopefully this is not your problem but easy enough to look into.
Carl in Virginia
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jlwhitney35
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Re: Engine wants to die when put into gear

Post by jlwhitney35 » Fri Jun 07, 2019 7:56 pm

So I removed the fast idle assy. and that has not resolved the issue. I did take the assy. apart and cleaned the innards, there is a cylinder and spring inside, neither of which seemed to be moving smoothly and the cleaning has resolved that. Air flow through the hoses is unimpeded.

The engine idles fine, mixture and idle set properly, timing to 10 degrees now, very smooth. Pushing in the clutch pedal does not alter anything, still idles smooth but engaging any gear causes it to die. I can keep it running by pressing the accelerator but it is no longer smooth, almost like its not firing on all cylinders type of rough.
Brake pedal does not alter anything (I think that was a question earlier).

I'll check the clutch tomorrow Carl.

Thanks again. So close but yet so far.

Jeff
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miker
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Re: Engine wants to die when put into gear

Post by miker » Fri Jun 07, 2019 9:06 pm

And pressing the clutch and brake pedals together but leaving it in neutral, everything is OK?

I'm thinking bad engine to body ground, where the clutch cable is serving as an alternate ground path.
Last edited by miker on Fri Jun 07, 2019 9:50 pm, edited 1 time in total.
MikeR (mirafiori.com since 1995)


1977 Fiat 124 Spider
Previously owned:
2012 Fiat 500 Prima Edizione #236 (now owned by my son David)
'86 Bertone X1/9
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'78 Fiat 131 four door
'76 Fiat 128 4 door
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bartigue
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Re: Engine wants to die when put into gear

Post by bartigue » Fri Jun 07, 2019 10:12 pm

Kind of sounds like it doesn’t it? Like the motor isn’t grounded at all.
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Brad Artigue
1969, 1969, 1970, 1979, 1980, 1981, 1982, and 1982 124 Spiders
1969, 1970 850 Spiders
77 X1/9
http://fiat.artigue.com
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miker
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Re: Engine wants to die when put into gear

Post by miker » Sat Jun 08, 2019 12:20 am

I was thinking that you would get weak spark and maybe even the idle stop solenoid closing with low voltage.
MikeR (mirafiori.com since 1995)


1977 Fiat 124 Spider
Previously owned:
2012 Fiat 500 Prima Edizione #236 (now owned by my son David)
'86 Bertone X1/9
'81 Fiat Spider 2000 #236
'78 Fiat 131 four door
'76 Fiat 128 4 door
'74 Fiat 128 4 door
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bartigue
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Re: Engine wants to die when put into gear

Post by bartigue » Sat Jun 08, 2019 4:24 am

I’d at least try it as it’s simple and doesn’t require removing anything. Buy a ground strap from an auto parts store and run it from the bolt holding the coil to the fender wall to one of the bolts on the motor mount. Measure in advance and add a little slack to it.

These can be bought at any auto parts store for a few dollars.
-----------------------------------------------------------
Brad Artigue
1969, 1969, 1970, 1979, 1980, 1981, 1982, and 1982 124 Spiders
1969, 1970 850 Spiders
77 X1/9
http://fiat.artigue.com
jlwhitney35
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Re: Engine wants to die when put into gear

Post by jlwhitney35 » Sat Jun 08, 2019 8:52 am

miker wrote:
Fri Jun 07, 2019 9:06 pm
And pressing the clutch and brake pedals together but leaving it in neutral, everything is OK?

I'm thinking bad engine to body ground, where the clutch cable is serving as an alternate ground path.
Yes that has no effect.

I"ll pick up a grounding strap, certainly is worth a try at this point.

Thanks to all for the input, I'll update later.

Jeff
jlwhitney35
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Re: Engine wants to die when put into gear

Post by jlwhitney35 » Sat Jun 08, 2019 3:24 pm

friedman wrote:
Fri Jun 07, 2019 7:43 am
The symptom I'm talking about is rpm drop or engine dying at idle by merely engaging the clutch, still in neutral, no shifting of gears.
I mention this as I recently had a problem with my X1/9 showing these symptoms when engaging the clutch and it turned out to be the crank thrust bearings having fallen out of place and allowing the clutch engagement to push the crank shaft enough axially to try to kill the motor. Easy enough to check by prying on the crank pulley to see if there is so much play that you can see or feel the crankshaft move axially.

Hopefully this is not your problem but easy enough to look into.
I just re-read your post, more thoroughly.
First, there is no slop on the crank pulley, I did as you suggested.
Second, the issue doesn't show when all I do is engage the clutch, still in neutral and no shifting of gears. The only time it dies is when I actually engage a gear, any and all gears.

I'll try the ground strap in a few minutes.

On a side note, I reinstalled the fast idle assy. just to see what would happen and there was no difference. There is a button on the fender well inside the engine compartment that , when pressed, cuts off power to the fast idle circuit, so it seems that the entire assy. works (if that is what the button is supposed to do).

Does anyone know, where is the grounding strap (the original that was part of the manufacturing process)? Is it on the transmission to the starter motor? I do have a large (wrapped in green) cable that runs from there, I remember it from when I installed a new starter motor.

Finally, just guessing here, would the coil have any bearing on this?

Back to it.

Jeff
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