I have a 2000 s 40 Volvo that intermittent won't start the lights are on o the das. If I wait awhile it starts up. Ive had the electrical starter switch sat replaced and did not work.

check for alternator and starter motor functioning ok , does it turn over and not fire up or not turn over at all?

The problem was not your 100 dollar starter. It was your 1 dollar fuse relay. Located in the fuse box under the hood, not the box in the car. The panel in question has a lot of square metal "fuses". The inside of the lid should tell you which one it is.

Intermittent electrical problems are the worst to diagnose.
One thing you have not replaced yet is the key switch.
I would run a wire to the starter solenoid terminal that has the wire from the key switch and have a meter ready for the next time it fails to crank.
If you have no voltage on that terminal it may be the key switch. You can also jumper that wire to battery power to see if it will crank by putting power directly to the starter solenoid.
I am assuming the security light is not on when the problem occurs.

first thing to do is get the car not to crank and check for power to the starter. if the starter has battery power and signal from the ignition switch then the problem is the starter. second thing is to check the plug at the trans range switch. the connector may be loose since you just had the trans repaired. ground may be an issue but not likely since the dash lights and other things work. GOOD LUCK.

you will need to try to turn the engine manually to make sure its not frooze. if it turns then you might need to check the starter again.

When you say it won't start, do you mean it cranks but won't fire, or it just won't crank? If it just won't crank, you could be having an issue with the starter relay. The often become intermittent before failure. Many owners do not know there is a starter relay because it was added as a recall item i order to protect the iginition switch from burnout. The starter relay is located in the very front of the engine compartment, just to the left of the battery, on the back side of the radiator crossmember.

sounds like you could have an intermittent problem with your crank position sensor. i had a 89 240 that did the same thing and i ended up having to replace the crank sensor

I had the same problem with the 2000 v70 XC I bought in Dec. 08. I replaced the battery, then the antenna ring (around ignition; part of the immobilizer system), and bought new keys as sometimes the chips in them do go bad. Also, if you have a key for another car with an immobilizer system on the same keyring, take it off. The multiple signals can confuse the immobilizer system. I think the antenna ring may have been one issue as, consistent with what repairpal stated, I got a crank and the engined turned over for about a second or 2 one time and then it died. The antenna ring (and the new keys) were relatively inexpensive. That worked for about a month and then I got no crank at all.  I had the starter replaced, but in hindsight I think that may have not been the problem.  I think the problem was the starter not getting juice. The starter was a very expensive solution. About 2 weeks after having the starter replaced, it wouldn't crank again.  I took it to a Volvo dealership and gave them the history. They found a corroded wire near the starter and, at least until now, that seems to have done the trick. Labor on the wire was about $100 at the dealer. Searching Volvo forums for those who have had a similar problem, I have found that others have had the "bad wire" problem.  If you are told to replace the starter by your mechanic, my advice to anyone having this problem is to have check to make sure the starter is getting juice before replacing the starter as replacing the starter (parts and labor) cost me about $650-$700.  If they find that the starter is not getting juice, they can check for wire corrision starting at the starter and working their way back.   

sounds like you need a new battery, it probably isnt running enought cranking amps to start your car, try a different battery and it should start fine