No start issue... Kind of

S

slow94

Well-known member
For the past few months my truck has been temperamental. I'm having an issue where the truck won't start without joggling back and forth between park and neutral. It will start up randomly in either. Sometimes it will start after a few key turns, and sometimes it takes 20-30 tries. The position of the shifter doesn't seem to matter whether it's park or neutral. I did replace the mlps sensor when I swapped in the A1 built trans but I still have the same issue. I get key on power and pumps will prime, but it just won't engage the starter. I'm thinking I need to replace the ingnition/key cylinder but perhaps there is something else in between there and starter that would be easier to diagnose?

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Check the arm at the bottom of the shifter tube on the column to make sure it's tight. Those are notorious for loosening and causing problems like this. It's held on with two torx screws. I usually take them out and locktite the piss out of them instead of just tightening them. When that arm gets loose, most people just start slamming the shifter into park to make it work and eventually break the shift tube.
 
So went and got a new solenoid just in case it was that easy and it wasn't. Wouldn't start with the new solenoid either. So I left key in start position, jumped the solenoid and truck started up. I thought that would mean the solenoid is junk? Can key switch do the same?

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oilwell1415 said:
Check the arm at the bottom of the shifter tube on the column to make sure it's tight. Those are notorious for loosening and causing problems like this. It's held on with two torx screws. I usually take them out and locktite the piss out of them instead of just tightening them. When that arm gets loose, most people just start slamming the shifter into park to make it work and eventually break the shift tube.
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I agree, I have had a loose shifter arm cause me issues. It was the first thing that I thought of after reading the thread. And it’s a free fix. It’s way up in there. Get the flash light out.
 
SVT1077 said:
I agree, I have had a loose shifter arm cause me issues. It was the first thing that I thought of after reading the thread. And it’s a free fix. It’s way up in there. Get the flash light out.
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I actually did do this a few months back to take some slop out of it. It did tighten it up a decent amount but still not like new. I would say it's acceptable right now. I could always use a momentary push button to jump solenoid and just call it "push button" start lol.

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If moving the shifter around makes it start I'd say the switch is probably fine and you've got an issue with MLPS/shift cable/shift linkage adjustment somewhere. If you hold the key in start and move the shifter from park to reverse to neutral to drive does it allow it to crank in places as you move it? Or will that column even let you try that? You could also put a test light on the wire where the start signal enters the MLPS and see if it lights with the key in start. If it does you know the issue is downstream of that point and if it doesn't you know it's upstream.
 
ive had to slam mine in park a few times for the same reason.

id lean on the park/nuetral issue causing a no start situation. loose wire from the mlps like mentioned above.
 
I'm still searching for the issue but for the time being I just disconnected the wires from my nitrous purge and run it to my solenoid relay. Just turn key and push button. Works every time now. Don't plan on keeping it like that but for now it will suffice.

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well thats using your brain lol.....

it sucks we have to learn an entire wire harness, wire color, become an electrical engineer, grab a volt meter like a pro and trace and find the issue real quick.

im not sure about the lightnings but the f150's i think had a tsb to update the MLPS switch on the trans for causing a lot of wierd no star issues. in fact, i need to search that since my 4 low quit working, its based off of vss and mlps position, powered by the ignition, just to turn on. sounds like a weekend with no kids and a bunch of beer
 
jetski247 said:
well thats using your brain lol.....

it sucks we have to learn an entire wire harness, wire color, become an electrical engineer, grab a volt meter like a pro and trace and find the issue real quick.

im not sure about the lightnings but the f150's i think had a tsb to update the MLPS switch on the trans for causing a lot of wierd no star issues. in fact, i need to search that since my 4 low quit working, its based off of vss and mlps position, powered by the ignition, just to turn on. sounds like a weekend with no kids and a bunch of beer
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Thing is when I put in my built A1 transmission I swapped the mlps sensor out for 2 others and the problem persisted. So I have new mlps sensor, new starter relay solenoid, a cluster that's been fully repaired, and I have tightened the screws to steering column. I know it's probably not great to be able to engage starter at any time but for now my redneck engineering is working.

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There is a push bottom kit that allows you to replace keyed ignition with a push button start. I wonder it that would work for you here.
 
im sure there is a test procedure for it, ive been using a screwdriver on mine for years and works somehow. except cruise control and 4low.
 
Having had a half dozen vehicles now with push-button start, I do get annoyed sometimes having to dig my key out of my pocket. That's a neat setup! I couldn't possibly care less about the alarm, but the proximity unlock and push-to-start would be awesome to have.
 
first time i saw the proximity unlock was from a ups guy years ago when i was still a mechanic, and thought, this is what i need for my toolbox so my $#!+ won't keep walking off.
 
slow94 said:
I'm still searching for the issue but for the time being I just disconnected the wires from my nitrous purge and run it to my solenoid relay. Just turn key and push button. Works every time now. Don't plan on keeping it like that but for now it will suffice.

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Silly question but did you align the MLPS correctly? I think you put trans in neutral and align the two marks. It can definitely cause problems if it’s not done.


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