S40 19T cranks for half a second, and only half a second. I'm stumped

start
volvo
s40

#1

This 2000 Volvo S40 19T wont start. Here is what I have done about it…

New Battery

Starter bench tested (Good)

New alternator (Bad diode)

Cleaned connections on battery, starter, and alt.



The car cranks for half a second, just enough to move the timing belt about an inch or two. But to get it to do this, you have to turn the key from positions 1 to 3 quickly. If you sit in position 2 for any amount of time, then position 2 has no effect on the engine at all.



Any ideas as to what it can be? I have checked relays and fuses I believe.



Thanks!




#2

A new battery off the shelf generally doesn’t have a full charge. So was it actually fully charged? A new battery could also be bad off the shelf. Have you at least put a voltmeter onto the battery? I’m asking because all of this just sounds like you have a dead battery.

Cleaning the power/charging connections sometimes isn’t good enough. Peel up some of the insulation to get a gander at the condition of the wires underneath.


#3

I will look some more at the wires, the battery is not the problem. I have replaced it with a battery out of a working car. The battery has just been replaced a year ago in this car so I know it has the right current.

Thank you!
-Dave
I dont know what else could be in the circuit
Here is what I have eliminated
_Battery
_Alternator
_Starter
_Starter Solenoid

What do I have left
_Wires
_Ignition
_ECU
_Neutral shutoff switch?


#4

Hey,Lavid2002, my 2000 S40 also has that kind of annoying problem. My car’s story began with a weird sound in the engine one day, I had a neighbour check the car he said maybe it’s the coil. So I had my car tolled to the mechanica, he changed the coil. Two days later in the morning battery died, I had the battery changed, then two weeks later one morning the car wouldn’t start. I called the toll service again, the toll truck driver arrived, helped clean the connections on the battery and he checked the battery, the battery was good. He hold the key longer than I did and the car groan for half minutes reluctantly started. I drove the car to my mechanical he said I had to leave the car in his garage sitting overnight then he could check weather it will start. The car sitting there for 2 days and it started as any time as the mechanic aproached it. I took back the car with nothing out of the problem, but it happens sometime still, and the most annoying thing is when the car started with the kind of groan sound the engine seems unstable during the running, it feels the engine will accelerate by itself. What that could be! Is anybody has any idea about that?


#5

Need a clearer picture of what’s going on. After the half second, does it make a high pitched whine that winds down in a few seconds or does it just stop turning the engine? If it just stops turning the engine, is there a clicking sound?

Have you put a torque wrench on the crank bolt to see how much torque it takes to turn the engine? Have you removed all the spark plugs to see if the engine will crank with no compression holding it back?

Is it an automatic or manual transmission, if manual, is it in neutral?