i have a 1990 volvo 740gl. it seems that on hot days my car has a harder time starting up. usually you just turn the key and it starts up. now on a hot day you have to turn the key and hold it there for several seconds before it starts. and a cople of times this has happened: on a hot day i turn the key and then hold it and i think it's gonna start so i let go. it pretends to start and then dies on me. no matter what i do again, it won't start. maybe half a day to a day later i go back to start it, it starts again. does anyone out there know what could be the problem? one other thing is that it's not a problem with my battery because i only got that battery replaced a year or so ago. anyone who know's anything about this please help me out. thanks a lot

In addition to the other posts, all of which have good things to check out in them, I would:
1) make sure the plugs, cap and rotor are in excellent shape

2) replace the fuel pump check valve- when this is bad, it takes longer for fuel pressure to build up to a high enough pressure to actually spray anything through the injectors. COuld take several cranks of the engine for there to be enough pressure to run.

See www.fcpgroton.com for great prices on all these parts.
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Rob Bareiss, New London CT ::: '87 244DL/M47- 221K, 88 744GLE- 202K, 91 244 181K, 88 244GL 145K

i used to have an 86 740 wagon with around 167,000 miles.. had some problems that sound like yours.. i had my mechanic replace the intake gasket as it was about gone and was telling the computer all sorts of wacky things because the engine was getting too much oxegyn which created a seriously rich mixture.. any way it made it hard to start when hot. Might want to take a look at this. Just throwing in my two cents..

This almost sounds like you have a vacuum line leaking somewhere. That will surely cause starting problems. Just check around your engine bay for vacuum lines and pay particular attention to connecting points. Might not be the problem at all, but easy to check and an easy fix if you find a leak.

Have you soldered the fuel pump relay? Suppresion relay? Heat expands the cold solder joints/ cold contracts and they work. Check it out.

I am experiencing a similar situation with my '89 740. I believe that my problem is related to the pre-pump assembly that is mounted in the gas tank. Over the past few months I noticed that it took longer to start the car when my fuel tank was near 1/4 full or lower. (Typically after the car had been sitting overnight or during the day for 10 hours. (Temperature did not have a big affect on this.) Many posts, here on the brickboard, mention this fuel pre-pump as a reason for this hard starting condition. I had my mechanic replace this pre-pump about a month ago, but when he installed it he noticed that the new pump was not turning on when it should. He suspects an electrical connection problem with the assembly that the pump is attached to - it includes the float for the fuel gauge and a sock type filter. He didn't repair or replace the other parts of this assembly because they cost around $300. He wanted me to try it without the pre-pump working and see if gas would flow through the new pre-pump easier. There is a primary fuel pump located under the car near the driver seat location. He thought that my primany fuel pump was strong enough to handle all the pumping action. The fuel filter is next to the primary pump. You might try having a new fuel filter installed if you have not had that done recently and see if that helps. I replaced my fuel filter about 6 months ago but it didn't help my problem. I have now decided that I probably need to get this whole pre-pump assembly working since my starting problems with a low fuel level have continued and actually seem to be a little worse. Recently, I've tried to not to let my gas gauge go below 1/3 full. I'm not sure why this problem might be worse when it is hot, unless it has something to do with increased evaporation. Did you ever notice a similar, but less severe problem during cooler weather when your gas tank was less than 1/4 full? (I assume that your 1990 has the same system as my '89.)