Ignition Switch - Starting Issue

O

okanaganowner

New Member
I have nothing to compare to so I hope someone can answer a question for me.

When I start my 81 Fiat X1/9 fuel injected engine the starter (rebuilt recently) turns the engine over easily. However the ignition system does not fire while the starter is actually turning. If I release the key, the car normally starts as the starter stops. That is, it would appear to me that the starter gets the engine rotating and then most times on release of the key, the system fires up and everything is great. Runs perfectly no problems.

Question: Is this normal in a Fiat X1/9 and if not where do you think the problem could be - a poor connection in the switch?

Thanks in advance.

Lindsay
 
Probably the switch...

It could be the multi-connector block that plugs into the switch harness, along the steering column, look for browned plastic on the white block itself.

But, it could easily be internal to the switch. The terminals inside carbon up, corrode, etc. which leads to resistance and/or failure.

This is an image of bad connections inside:
IMG_1091.jpg


The best thing to do is get out your test light and start checking the function of the switch.

Another possibility is insufficient grounding somewhere, so that when cranking the starter takes all the ground potential, starving the ignition of ground. This same effect can be on the (+) side as well if the battery is marginal, or if the battery terminals are dirty, loose or corroded. The F.I. ECU is especially finicky when it comes to sufficient voltage.

Hope this helps.
 
Also Lindsay... I believe a WELCOME is in order...

I don't recall seeing you onboard before.

I would say it is OBVIOUS that the power consumed by the starter is drawing so much that here is not enough voltage to the ECM for it to operate until you lift the key from start to run, and there is enough momentum of the engine spinning, and NOW enough voltage to trigger the ECM and for the coil to charge and discharge.

I TOO HAVE EXPERIENCED this very phenomenon. I have a few ideas that might help.

First, check the 4/5 wire connector from the ignition switch to the harness under the steering wheel cover. Make sure no wires are burned and the connector is not fried either. If you want... pull a drawing and use a voltmeter and PROVE the following.

Find the power lead to the ECM and crank the engine. Look for 12+ volts, I bet you'll see about 11.

Then do the BROWN WIRE MOD (BWM) found in Best Of. Many ways to do this... but after its done, it fixes a bunch of problems. Retest the ECM lead and it should be 12+.

Also check your GROUND STRAP from the trans to the frame behind the LR tire... remove, sand the surfaces, and reinstall. Another strap of sorts bolted to the cam cover and body up top will doubly ensure you have good continuity.

Let us know how this works for ya... HTH...

​
 
In time, Fiat Ignition swiitches will fail to activate the starter. This is the most common failure, I'm guessing 85% is the % of failures.
The other 15% would be failure to supply Ignition current, and curent for other circuits. 2 seperate circuits supply current to the Ignition. #1 is in the starter cranking position, #2 is in the on position with the engine either running or at rest.
The easy way is to get a new switch, and plug in it to the harness. If that cures it, you're done. If not, I don't feel it's a loss, as you'll need it someday.
The other main failure is where the switch plugs into the main harness. Connections over heat and lose conntact. You can see that easiley. I've had to wire around burnt wires/connectors at that junction.
 
The only problem with that...

...of course...is the availability of these switches.
 
Look for the obvious signs of burning at the connector where the brown wires are located, mine was fried so I directly connected the brown wires.
 
Thanks for the help

Thanks for all the suggestions. I will now have to find some time to attack the problem. Car is off the road for the upcoming winter so it may be some time before I get back with the final results.
 
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