Frank;

Welcome to this Forum!

Congratulations on your ES acquisition!

You don't state your level of vintage car ownership or wrenching, or fuel injection experience (this is probably not a good starter vintage vehicle, but if it is, you have a lot of learning to do and it will happen fast!), here are some thoughts to your symptoms...

"pretty strong smell of gasoline in and around the car"...inspect carefully along the ENTIRE Fuel System for stains of fuel where it might be weeping (or out and out leaking) out of joints or even the continuous hardlines between Tank/FuPu area and engine compartment. Beware...fuel-lines downstream of FuPu are pressurized and will/should maintain this pressure (2 Atm) for at least a while after Ign shutdown. When opening pressurized lines be ready for pressurized release of fuel...USE OPEN FUEL SAFETY PRACTICES!

"venting filter that I am suspecting needs to be replaced." ...based on what? Be careful about presumptions or shotgun troubleshooting (defined as throwing all sorts of replacement parts at a problem without root-cause troubleshooting.) Volvo Service Manual should be augmented by info in D-Jet Fault manual. See: http://www.sw-em.com/bosch_d-jetronic_injection.htm#volvo_fuel_injection_fault_tracing and the Bosch Injection book will be the best $20 you ever spent!

"quite a miss which may be a result of the electronic ignition being bad (easily found)"...agreed
", or maybe a bad ECU. But I don't see a source for ECU's?"...that's because you don't need a source for ECUs! (not initially anyway!)...D-Jet ECUs are highly reliable and should be the LAST thing to be suspected and replaced as they are not cheap...before even thinking about replacing ECU, you should assure electrical connections at FI Sensors and ECU, and constant fuel delivery and pressure (including under engine load i.e. high fuel demand), measured at Fuel Rail which supplies injectors, see: http://www.sw-em.com/bosch_d-jetronic_injection.htm#Measuring_Fuel_Rail_Pressure , and good Injector spray pattern...and not sticking Fuel Pressure Regulator or Cold Start Injector leakage...etc.

Before throwing replacement parts at your car (often the old parts simply need checking and degumming!, not replacement!), you need to edumacate yourself on what you have gotten into, unless you want to needlessly spend a lot of time and money and maybe still not make progress (this is often what the last owner might have done, before he gave up, and moved the car along...D_Jet cars with problems are cheap to buy!) You need to develop your info and parts resources...Forums, Pbanders site, Bosch FI book, Dr. D-Jet site, Planetman (Eric), Don Thibault, all easily found or linked on above linked page. Know that you CAN have a good time with a D-Jet 1800!...it might (probably WILL) just take some dedication!

Most if not ALL problems on these cars have been experienced and in many cases are well documented, and symptoms and remedies are fairly well known...this is where I would advise you to start your journey with this car. Hopefully I have not discouraged you, my intent was to give you a good start!

Good Hunting!