The car in question is a 1985 240. When cold the car fires up within 2-3 seconds of cranking. But if I get it up to operating temp and shut it off and go in the store and come back to try and start it, it takes about 8-10 seconds for it to fire. A small inconvenience but one that I want fixed ASAP. Any help would be appreciated.

 

Change the fuel pressure regulator, it's not holding pressure.

 

Even though it starts up easily after it fully cools down?

 

try this next time when its doing this. switch it off, then back to II (Run) wait a sec, turn it off and back to II, wait a sec THEN III (Start)... when you turn it to II, the fuel pump runs for about a second. many people just turn it straight from off to III and that doesn't give the fuel pump a chance to develop fuel pressure.

other possible causes... when was the last time the car got a 'tuneup' ? (New plugs, distributor cap and rotor, plug wires, air cleaner, fuel filter, ...)

a marginal coolant temp sensor could be throwing off the warm start timing.

 

I would have to agree with Lev on this one. At least on my Mercedes - which has a similar LH fuel injection setup - I was having longer cranking times on warm starts. The issue was the fuel pressure regulator.

 

you might be misremembering. turning the key to II does not cause the fuel pumps to run for a split second (for either an ‘87 or ‘88 DL)

 

You are correct - it doesn't on LH2.2. It does for LH2.4 & LH3.1 which is '89 and on.