mojave3555

hi all im having a problem with my 95 4x4 3vze it started a while back but has gotten progressively worse over time it used to crank and start just fine then on hot days or after driving the truck a bit as soon as you turn the key it just clicks not a solenoid click but a relay click under the pass kick panel i think thats a efi relay but anyways as i was saying it used to do it only when hot now it doesnt want to start at all and when i say start i mean crank engine wont even turn over so i did what most of you had done and replaced the solenoid and contacts in the starter thinking that would solve the problem but no the starter bench tested just fine but as soon at its in the truck no go i checked voltage on the solenoid signal wire and with the key turned the signal wire would only show 6 volts then climb slowly to 8 or 9 volts now when i put 12 volts directly to the signal wire it turns over like its new i tracked the signal wire to the efi relay under the pass kick panel and it gets the same voltage as it does at the starter and thats where im lost i took apart my ign switch cleaned brushed and filed all the contacts still no change charged the battery to where i was showing 14.5 volts everywhere but still 9volts max at the signal wire with the key turned to the start position so if anyone has any advice suggestions prayers... lol anything will help at this point trucks dead in the water and i have a huge desert to go play in!! help!!

scope103

Good job so far on following the voltage.

The solenoid wire is switched by the starter relay, in RB-2 under the hood. http://web.archive.org/web/201204170.../2powersou.pdf The relay is probably bad, but you should test it first. http://web.archive.org/web/201102051.../2starterr.pdf

Here's some photos of the starter relay. https://www.yotatech.com/forums/f116...switch-287859/ Consider using a jumper as I show, to demonstrate (to you) that if the relay were good it would turn the starter. You don't want to be buying a new relay when it won't make any difference.

The EFI relay (labeled MFI in the manual) is also in RB-2. The relay above the passenger-side kick panel is the Circuit Opening Relay, which powers the fuel pump, and is closed with key-to-start.

mojave3555

i think my fuse /relay block differs from yours a bit lol and the fuel pump relay seems to be connected to the solenoid somehow? or maybe they share a circuit idk

RAD4Runner

Good troubleshooting.
Good tracing. (Yes, That EFI / C.O.R. relay also gets power from the starter relay when attempting to crank.)
Like Scope says^^^ relay could be bad...
... OR it's not getting the right power from the correct source.
Schematic I have of 1990-1995 truck looks correct but there are so may variations out there; it's best to verify. Please check pin5 of starter relay. Should have a white wire going to it. Should always have 12V even with IGN switch OFF or key released. When relay clicks, you should get 12V as in check that Scope103 refers to.

Yotanewby

Hmm...

mojave3555

after doing some reserch it seems that my truck being an automatic might not even have a starter relay?

RAD4Runner

Correct. . See this...

mojave3555

so if i could just wire up a ford solenoid to run off the original solenoid signal wire which as stated above is only getting about 8 volts and run a battery cable from the positive post thru the ford solenoid and then to the solenoid on the starter that should theoretically work yes? or is 8 volts too little to kick the ford solenoid?

RAD4Runner

OOPS! Sorry I forgot that you mentioned this... (That's why it's always good to have truck-model-year-engine-transmission in signature.)

Proper, clean solution is to check your wiring to make sure it is wired according to "correct schematic" as I posted above.
If wrong wiring fix it per schematic.
Or take the shortcut (still clean) and

Yes, adding the Ford Relay*, or any proper relay IS THE CLEAN AND ROBUST SOLUTION. Are u getting 8V with stock starter solenoid connected? That is as expected with load. If you still get 8 V even with solenoid disconnected, your neutral safety switch could be bad, dirty, or have bad connection. Ideally you'd want 12V there without load. Not sure how much it would take to energize the added Ford RELAY, but worth a try. Having a RELAY there is essential. So is making sure your NSS and connections are good.
​​​
*(I prefer to use "solenoid" for something that also has to actuate a mechanical part OTHER than plain electrical contacts).

wyoming9

iTrader: (1)

I am thinking sand in the plug for the neutral safety switch .

Then it might be other connections also

The spade connector for the starter solenoid is another place

Just enough increased resistance to drop the voltage

Your naked eye might not even see the corrosion and dirt .

You also need to remember meter probes can get a good connection but when plugs are reconnected things don`t work