1991 Volvo 740 2.3 L4 non-turbo

I bought it a couple years ago for family trips. It has had this problem from the first rainy day I tried to start it. Took it to a mechanic that claimed it just needed new plugs,wires and dist. cap. I recall it made it throught a couple rainy days then it wouldn't start again. I removed the coil, coil wire and plug wires and applied dielectric grease (I was told to do this to an '89 Ford Mustang I use to own with the same problem. I was also told to spray something on the inside of the dist. cap but can't recall what). This worked for quite awhile. Recently, it started doing it again and I can't get it to start at all now. I really need to start it. The alt. on my truck locked up and fried the serp. belt.

Suggestions Please

 

Get it down to the basics. does it crank? pop the wire that goes to the dist cap and see if a spark will arc to the block. Then listen for the fuel pumps. The one inside the tank can be heard by using a hose stuck into the filler cap as the key is turned forwards. the main one can be heard as you turn the key forward. then pull the injector rail off and make sure the ground for the injectors is still attached and see if there is spray.

Then go to basics. Pull off the air mass meter, air intake pipe to the throttle body, throttle position switch connection, idle air control valve connector, and other computer stuffs. pull the injector wires and crank it for a bit to clear it out if flooded. plug the injectors back in and try it.

If that doesn't work, pull the plugs, clean them and crank with no plugs to clear it out. Put plugs back in and fire it up. That is as basic as you can get and it has to run in that mode. If not, you got something major. Slowly connect things back up and see what makes it die. Also, use dielectric grease on all connections you see and grounds that you see as you work.

 

thanks for the suggestions mikkowus. I am going to try them right now.

I was out trying to start it before I read your suggestion and I noticed that the tach moved while trying to start but would drop back to zero after a few cranks. A couple of times I saw that the tach did not move at all when it cranked. Perhaps this is a clue.

 

Yes it cranks. The coil wire produced a little blue spark when I touched it to the hold down nut for the ground wire. Heard both fuel pumps (didn't know it had two). There was two wires attached to the two rail brackets (the ground wires I hope?). I unbolted the rail, removed the clips and injector wires. I tried to remove the rail but it would not come off. I was apprehensive about prying it off for fear of breaking it.
Removed the mass air meter, air intake and what I think is the throttle position. Not sure what the idle air and other computer stuffs are but I did remove the injector wire, crank it then replaced the wires.
I haven't tried removing the spark plugs yet because the battery was going dead and I put it on charge.

 

was having the same problem with my 1990 240dl , it would crank but not turn over. what i found was that there is a 25amp inline fuse coming off the positive side of the battery if the connection is bad it wont start, dose your radio come on if not check the fuse, car should start if radio comes o.