just picked up my first volvo 940, 94 model. not running and got it for $300.

it's not getting gas. spray ether in it and itll run for a second and cut off. fuel pump is squirting gas.

this is leading my mechanic to believe it's the injectors or control module. the car has been sitting about a year and a half and has bad gas, so having clogged injectors wouldnt be out of the question.

any other possibilities? would it be possible a code has been set and if so, how do i read it? all ive had so far have been 80's 240s (and an 09 s40). oh, and according to ipd, these cars had 2 different injection systems, how do i tell which? the module in there currently is a bosch, but i dont know if they could have replaced that with the wrong one. this one is a base model, 2.3 automatic nonturbo.

thanks in advance!

 

make sure the injectors are getting power. disconnect one of them (they are all wired in parallel, exactly the same), and ignition to II (run), then take a volt meter, ground probe on the grounding rail, and plus probe on one of the two pins on the plug that went into the injector, and you should see +12V. you can use a 12V test lamp instead of a volt meter. the other pin will be 'floating', so will give semi-random readings that might also look like 12V to a volt meter (the ECU grounds the other pin to fire the injectors).

if you do NOT see injector power, the first thing to check is the 'radio suppression relay'. bad name, its actually the 'fuel injector power relay'. this relay is probably on the right fender, behind the right headlight. see http://www.davebarton.com/pdf/1994-9...ylocations.pdf (on a turbo, its on the left side).

warning, the relays sold at NAPA/etc kinda parts stores are often the wrong ratings, they might work but they might not last long, I'd get the proper relay like Volvo Multi Purpose Relay - KAE 1323592 | FCP Euro

 

re ECU, the Regina system is *completely* different, the ECU wouldn't fit. Bosch cars have a 'MAF' (Mass Air Flow meter, sometimes called a AMM) in the air path between the air filter and the throttle body, this is clearly labeled Bosch. Regina cars have a intake air temp sensor, that looks very different.

MAF:


Regina:

 

I printed off that relay sheet and went out to the car. i found that the one labeled "E Fuel Injection" that's in the center stack is missing (this seems to be the same relay as from a 240 that's behind the glove box). so i took my relay from the 240 and placed it in there and it matches up, but it just "flops" like there is not plug in holding it in.

is this relay not needed and the slot is a blank or do i have a problem? is the relay under the hood used in place of this relay?

 

on 1994,1995 940 non-turbos, they got rid of the traditional dual relay in position E (middle row, left side), and instead use the 'radio suppression' relay under the hood for the ECU and Injector power, and a new simple relay in position M (2nd from right side of the closer row) for just the fuel pump.

 

thank you sir, that answers that question.

we'll get to work on checking out the power to the injectors.

 

some history explains this whole relay thing a little better.

first, early 240's had two seperate relays, behind the glove box, one turned on the ECU and injectors and stuff, it was controlled by the ignition key, and the other relay turned on the fuel pumps, it was controlled by the ECU.

later 240's used a dual relay to do this.

the 740 centralized the relays under the console, which unfortunately was directly beneath the radio. the current pulses from the injection power was causing AM radio interference, so they added a 3rd relay under the hood to provide the injector power, this 3rd relay was slaved to the ECU half of the dual fuel injection/pump relay. They called this 3rd relay 'radio suppression' since it was added to stop radio interference, but it is really the 'injector power relay'.

by 1994, they realized that was redundant, so they dumped the dual relay, and ran the ECU off the radio relay (which is switched on by the ignition), and added a seperate simple single relay to power the fuel pumps. electrically, this was directly equivalent.