F355 won't start or crank - despite new starter & battery

Romove right hand engine bay side cover to expose positive and negative main terminals. Check there is a healthy (>12.7V) voltage between +ve & -ve terminals.

If voltage low then you have a cable problem twixt battery and engine bay (assuming battery is healthy). Need to trace through main power cables and find problem/clean up terminal post connections etc.

If voltage is OK turn on ignition. Ensure gearbox is in neutral. Use a length of wire to connect from the positive terminal post directly to the solenoid on the starter.

If engine cranks well then you have a problem in wiring/connectors twixt ignition switch and starter solenoid. This is usually due to light corrosion on the wiring loom connectors. Trace wires and clean connector plug/socket pins etc. Alternatively you can fit a local relay in the engine compartment - use the ignition switch feed to the starter solenoid to 'fire' the relay' and a positive feed from the main positive terminal in the engine bay through the relay to the stater solenoid - this, of course, just masks the voltage drop/high resistance in the wiring loom and compensates for it.

If the engine does not crank well then you may still have a problem in the main cabling from the battery to the engine bay to the starter motor which only shows up at high loading or the starter motor, despite being rebuilt, isn't functioning correctly.

Hope this helps.

 

Had the same problem....turned out to be the broken clip attached to the starter....took me a week to figure it out and solved it with a 15-cent part.

Then my headers cracked the same day I fixed it. $3000.

Check that connection to the starter. -Brian

 

good advice, recheck all the battery cables lugs including grounds

 

I had a similar problem. I would turn the key and some times it would immediately start. Other times I would have to hold the key in the start position for 5 seconds or more and then suddenly, without reason, the starter would engage.

New battery - same thing.

Rebuilt starter - same thing.

Tested starter at electronic shop - all good.

Reinstalled - same thing. Checked for power and had 12 volts at the coil even when the starter wasn't cranking.

Finally bought a NOS starter (FerrParts) - that was 12 months ago and not a single problem.

I think my starter had a small break in the motor windings and would separate at high & low temps. I bench tested it and it works fine on a bench. Put it in the car and heat it up or let it sit outside in colder weather...won't start.

Fun times.

 

Juat because its rebuilt doesnt mean it will worl. Did he bench test it since the problem came back?