Unusual hard start problem

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TonyB
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Unusual hard start problem

Post by TonyB »

Engine is a 1.6na with fuel at the injectors, new glowplugs (working), rebuilt injectors, good battery and good cranking speed. I crank the engine for 15 seconds at a time and it will start maybe one out of 3 or 4 times, Every time it starts it is just as the key is released from the start position.
Does anyone have any thoughts on this. The only electrical part I can think of that might be related is the fuel stop solenoid. The voltage measured at the solenoid when not cranking is 12.8, dropping to 11.5 when cranking. The solenoid clicks when battery voltage is applied.
Once started, it runs fine. A few marbles with cold start in, more marbles with cold start out. I have not checked or adjusted the timing.
I'm not one to start replacing parts w/o a good diagnosis, but I'm about out of ideas on this one. Has anyone had an experience like this? I sure could use some help. Thank you.

TonyB
81 Dasher 1.6na
Jacksonville, FL
82vdub
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Post by 82vdub »

If you do have fuel at the injectors and the glowplugs are definately working, I'd suspect the fuel shutoff solenoid. If it does only start when you let the key go, there was another person that also had a hard starting issue and they found that the fuel solenoid wasn't getting voltage every time the key was turned to the on position. To test this, jumper out from the battery to the fuel solenoid. If you have the jumper wire, this test should iron out any fuel solenoid/ignition switch wiring issues as it should start pretty reliably.
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idhoho
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Post by idhoho »

The problem could possibly be in the ignition switch. I had an '81 that would start but then immediately die when the key was released....unless you held it in just the right spot. Diesel Ign switches are different from gassers too. So, if it isn't the fuel stop solenoid, it might be the switch. You only need the switch itself- don't hafta change keys.
tawney
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Post by tawney »

I agree that it sounds like a bad ignition switch. 82vdub's solution could give you the answer; also, you could run a wire from the fuel stop solenoid to a test light in the car. That way you would be certain when the solenoid is getting juice and when it isn't.
81 Pickup 1.6NA; '86 Cabriolet with 1.6 TD
TonyB
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Fixed!

Post by TonyB »

You folks hit the nail on the head! My ignition switch appears to be defective. Fuel solenoid has voltage in the on position, but none in the start position. Many, many thanks for the help on this one.

TonyB
Jacksonville, FL
81 Dasher 1.6na
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