OK, I know 940s are very reliable, and mine runs well, but I want to make it as reliable as possible. I've changed or will change plugs, cap, rotor, wires, water pump, timing belt, vacuum hoses and coolant hoses. Are there any other weak points? Like the crank position sensor on the bellhousing? Coolant temp sensor for the EFI?
Any info would be appreciated.
thanks,

Csaba
'93 945Ti,
'84 245Ti, lots of mods, sold

For sure the crank position sensor. It is a <$30 part and it can stop the car in it's tracks. It's an easy job to replace it.
--
94 940 112K ,98 V90 147K

hello
not sure if the 93 had the small coolant hoses at the oil filter housing for cooling the oil, but you might want to replace them two small hoses.
might want to check the radiator, if its a volvo its has a date code usually on passenger side, its blocked by the black turbo hose going into the intercooler.
if its a 93 its done its job.
clean the vacume nipples on the intake manifold, make sure the oil seperator box is clear.
what i carry in my 940 turbo
air mass meter
crank sensor
fuel pump relay
supression relay
power stage
ballast resistor
o.D. relay
extra fuses
good luck
mike

Mike,

> small coolant hoses at the oil filter housing for cooling the oil,

yes, I will change those.

>might want to check the radiator,

Good idea, thanks!

>clean the vacume nipples on the intake manifold, make sure the oil seperator box is clear.

Will do!

>fuel pump relay
>supression relay
>power stage

I do have a spare fuel pump relay (white relay, goes in left side of relay board, second from the front IIRC?), but what is the suppression relay and the power stage, where are they, and what do they do?

>ballast resistor

Is there one for the ignition, or are you talking about the 4 resistors for the injectors?
thanks,

Csaba

The (radio interference) Suppression relay gates +12V to Injector resistor pack* AND to the EZK Ignition CU.

*[I think this is what Mike is referring to as "ballast", because the ignition has no ballast resistor.]

The Power stage (aka Ignition Amplifier, also sold as "Ignition Module") triggers the Coil to generate spark. Search on any of these terms for more info.
[This is the only major ignition part I know of that can fail, but still allow FI operation. Symptom: No spark and wet plugs.]
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

hello Bruce.
the part i was talking about is on turbo cars only, i always called it the ballast resistor not sure exactly, but volvo calls it (part# 3531339 series resistance) and i only seen em on turbos, even my 240 has a simular one. i believe going from memory it can give you a no start and has something to do with fuel injection power.
heres a go at a pic. i found this one at the JY new in box for 5 bucks.
good luck
mike

Bruce,

>The (radio interference) Suppression relay gates +12V to Injector resistor >pack* AND to the EZK Ignition CU.

Do you know where is it located?

>The Power stage (aka Ignition Amplifier, also sold as "Ignition Module")

Aha! Now I know what it is, the module on the right inner fender.
thanks,

Csaba

On my non-turbo, the RIS relay is on the right (passenger side) inner fender, about even with the ABS module. Unlike earlier 700/900 cars, it is not interchangeble with the Fan relay, which is down in front of the battery.
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

In the 740/940 FAQs, there is a list of things to do or replace when you buy a 940. I'd recommend that you do all of the things on this list. I did this with my '93 940NA and it has been very reliable. My wife prefers it over our MBZ so I want ed to be as confident in its reliability as possible.

The only time it gave any trouble in 5 years was the crank position sensor went bad. I had this on my to-do list but had not gotten to it.

I would at least buy spares of the following:
-RPM Sensor
-Fuel Injection Relay
-Radio Supression relay.

If you want to be proactive, I don't think anyone could argue that at your car's age, it wouldn't be prudent to replace them as preventive maintenance. Why wait until the day when you're running late for work, it's pouring rain, and one of them decides to fail? If the replacements last as long as the originals, you should be good with them until 2021 -- at which poin, the car will likely have been long gone.
--
Jeff Pierce (Post back with your results... it's what makes this forum work.)

Maybe your fuelpump relay,The only problem Ive had with my 93 940t was a bad powerstage.