my '92 Ranger will not consistently start
every once in a while it starts, but the starter cranks the engine really slowly

any other time, the relay just clicks
I got the starter and the battery checked out at an auto-shop
both are in fine running condition

leads me to believe its the electrical connections, maybe a bad ground somewhere. Do I replace all wiring in starter circuit?

 

Replace only if the cables are bad. Usually, cleaning the connections is all it takes.

 

thats what i did before, and it worked fine for a good long while.
But i clean and secure the connections and it just keeps clicking

very frusterating

 

Your truck has both a starter relay and solenoid. The relay is on the fender and acts as a current limiter for the starter. The solenoid is on the starter itself.

The fender relay grounds thru the relay mounting bolt to the fender. Make sure this connection is clean and tight. Remove the small wire from the relay and using a jumper wire, connect the small terminal directly to the positive side of the battery. This bypasses the ignition switch. If the starter spins the engine over, you have a problem with the wire from the ignition switch, either no or low voltage.

If the relay still clicks, use one side of a jumper cable pair and jumper across the large terminals on the fender relay. If the starter spins this further indicates a problem in the area of the relay, or cables, or battery. The cables can be bad under the insulation, so a visual does not always give a good indication of the cables.

If the starter does not spin, check the cable from the positive side of the battery to the starter, and the cable from the relay. Make sure they are clean and tight. If everything checks out, you have a problem with the
starter/starter solenoid/battery, no matter the auto shop check. jd

 

I tried the ignition switch bypass, and it still clicked. But I haven't tried to jumper across the large terminals on the relay. I will try that next
I'm just getting the starter and solenoid checked at another place.
We'll see what they say

Thanks big and jd

 

Seeing as how you say the starter motor cranks slowly at times & it has responded favorably by cleaning the contacts, as has been said I'd suspect a problem with the heavy current carrying battery cables, or their connections, or the starter motors solenoid contacts, or maybe a problem with the starter motors bruhes, or a dead spot in the starter motors armature.

I once had an intermittent slow/or no crank condition, that was caused by a faulty B+ battery cable lug connector, being corroded, out of sight underneath the insulation where the wire strands made contact with the cables lug terminal. I learned later that those manufacturers cables were on a recall !!!! lol

A under load voltage drop test sniffed that problem out.

When the problem next arises, try parallel connecting the suspect battery cable with a good quality heavy gauge jumper cable & see if it'll crank, as that will yield the same results by process of elimination, if you don't have a multimeter to do a under load voltage drop test (while cranking the engine).

Seeing as how you don't have any other electrical complaints, I might begin by focusing my attention on the B+ cables connection at the starter motor end of things, the starter solenoid & starter motors brushes.

Good idea to have the system checked out by another place.
Most autpars stores have a portable electrical system tester, that can check your starter system, with all the systems components in place in the vehicle & most will do it at no cost.

When they do this, be sure to have them do a "wiggle" test of BOTH ends of the battery cables & a "thump" test of the starter solenoid & starter motor.

Just some more thoughts for pondering.
Let us know what you find.

BTW, welcome to FTE!!!!!

 

My Ranger likes starters, they must be tasty? I've been thru 2 in the past 7 years (Motorcraft) on my "88" while my 25 year old Toyota still has it's original. Replace your positive battery cable to the starter. Also, clean all your contacts and check your battery terminals. Ford wiring quality/design/layout sucks big time. I could write volumes about it.
I've had more issues with my Ranger than any other vehicle I've owned far and away. I bought the truck as it was the most bang for the buck at the time. Your issue appears to be the starter based on symptoms I have had.

 

If you have 4 hands and a VOM, you can check the voltage drop across the large cables. While someone is activating the starter, place the voltmeter contacts on the battery post and on the + post of the solenoid on the inner fender. There should be very little voltage registered. If there is a lot, your cables are not connecting very well. This is called voltage drop. If you have a drop - or difference - then you have poor connectivity. Either the conductors or the cable ends...
tom