No start issue

[Fwbdave]

First let me say I have read everything in the forums I could find about no start issues. I Have a 2000 4.0 sohc explorer. The wife calls and says the truck will not crank. Spins but no cranky. When I get there i tried it, no start. Metered all of the fuses in both boxes all are good. Tried to use ether through the mass air sensor and no start. Put the intake hose back on and tried it again just for giggles and it cranks right up. That was Friday. I checked it Saturday and it cranked right up. I figured it was a fluke. Went ahead and put new front shocks, new frt brakes and sway bar links. Drove it on a 120 mile round trip no problems. But I noticed the gas gauge and temp gauges were fluctuating. Monday morning she calls no start. I get there it cranks right up but the gauges are fluctuating. Tried her keys and mine. Same thing with either. I know it long winded but you need all the facts. Any ideas where to start?

 

[2000StreetRod]

cranks but intermittently doesn't start

So the starter motor cranks the engine every time you switch the key to start but the engine doesn't start and the gauges fluctuate when the engine is running. You obviously have an electrical problem and may have more than one.

Does the voltmeter fluctuate when the fuel gauge and engine coolant temperature gauge fluctuate?

Have you checked the battery voltage when the engine is off and again when it is running?

Have you checked for ignition spark when cranking the starter when the engine doesn't start?

 

[Fwbdave]

Does the voltmeter fluctuate when the fuel gauge and engine coolant temperature gauge fluctuate? .....no those are the only 2

Have you checked the battery voltage when the engine is off and again when it is running? .....Have not checked it but the motor spins very strong. Reasonably certain there is no problem there

Have you checked for ignition spark when cranking the starter when the engine doesn't start? .....No since the first no start it has fired up every time I get to it.

 

[2000StreetRod]

Fuse 11

According to my 2000 wiring diagrams the fuel gauge, engine coolant temperature (ECT) gauge and the voltmeter all receive power from the same source - Fuse 11 in the central junction box. However, the fuel gauge, ECT gauge and the oil pressure gauge are all connected to the anti-slosh module. You may have a bad anti-slosh module but that should not affect the starting or running of the engine. Which is why I suspected there are two unrelated problems.

Since the engine would not start on ether you probably have a spark problem. You might try disconnecting and reconnecting the crankshaft position sensor a few times to clean the contacts. It's exposed to weather and road grime. The PCM uses the sensor output to determine that the crankshaft is rotating and to time the ignition pulses.