240 Warm Starting Problems

My son has a 1986 240 non-turbo, that for the past two spring and
summer seasons has been hard to start when it it warm out. It is
aggrevating because during the cold weather it starts fine. Where do I
start to look?

 

Carbon builds up on the back side of the valves causing it to take more gas
to start. Gas contracts when it is cold meanig you actually get more gas
when it is cold. A corbon blast will correct the problem, but is it
worth it? Most dealers charge 2 1/2 to do it. Try a tank of Exxon premium
and a bottle of Tachron fuel additive.You will see a lot of charcoal looking
particles coming from the exhaust. That is the carbon build up breaking
loose. Should run better after that. Do it only once. The B230 doesen't need
high octane gas to run.

 

G and Rod:

I've had hard warm starting touble with my 84 B23F. My solution was to peel back the
tape on the wiring harness just ahead of the firewall (on the left side of the
connector) and locate the blue temp/sensor wire. Then, using a scotch-lock and a bit
of wire with a 47k ohm resistor soldered crimped in place, attach the resistor wire
to the blue wire, and the other end of the resistor wire to the free spade connector
on the starter solenoid. This arrangement fools the engine into thinking it is cold
and therefore deliver an extra dose of gas while cranking. This works for my 84 and
I won't vouch for the B230 but you might want to investigate issues with the temp.
sensor circuit. HTH, YMMV, ;_)! NickZ.

 

Nick has a valid issue here. I replaced many 240 wiring harnesses under
warranty.Volvo stopped doing it in 97. I have commented on this problem
before. Volvo wouldn't use PCV insulation because it gives off chlorine gas
if it burns. Remember Volvo is the SAFE car. The insulation would crack and
fall away from the wires on the main harness where it goes under the intake
manifold. Cut the sheath back at that point and inspect the wires. The wires
going to the air mass meter short out causing the car to stall. Tape them up
and you should be good if that is the problem.