our 1990 740 gl wagon has a fuel leak somewhere. the gas smell is very strong inside and outside the car. it use to start right up immediately but now you have to hold the ignition for about 4-5 seconds before it starts. where should i start to look for the leak? are there any common fuel leaks spots for the 740? i do not have a shop manual yet for this car so please be real specific with any advice. i have a haynes from my '90 240 dl though.

thanks in advance!

Your interior air intake is the grill just ahead of the windshield. As you smell gas fumes both in and out of the car, the leak is likely under the hood. A common source of that problem is a disconnected line on the evaporative control system carbon cannister. Find the carbon cannister which is a black plastic cylinder about 7 inches long and 4 inches in diameter. It should be buried at the left front fender down behind the front bumper. Make sure both lines are still connected. It's not that hard for the return line to get accidentally pulled off. However, if you smell gas fumes mostly as you get out of the car and it's most prevalent when the tank is full on a warm day then suspect a leak at the fuel sending unit on top of the gas tank. In particular the sending unit may not be properly seated in the rubber gasket or the locking collar threads may be stripped from overtightening. This may happen if the in-tank pre-pump or fuel gauge sending unit have been recently replaced.
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Dave -not to be confused with a real expert

Could be anywhere from the line into and out of the tank, under the car, into the engine bay. Since you hhave trouble starting it is probably not holding the pressure.
You're going to have to follow the fuel line and use your nose and eyes. Probably best to look just after shut down as leak should be noticeable then as opposed to when the pressure leaks out and the fuel evaporates.
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744-16v-4+OD 185kmi., 745-16v-4+OD 359kmi., 242Turbo-4+OD 170kmi?, 245DLT automatic 287kmi.. 245SE automatic 198Kmi.