1985 244 here. It'll fire up and run on ether, but won't on gas. Previous owner said it had a bad fuel pump. I replaced both with good quality Bosch, new filter, new sending unit, supply line and tank. All we crapped up with rotten gas and a huge amount of crud from sitting idle through Phoenix summers for 4 years. I have good fuel pressure at the rail, and must have spark if it ran on starting fluid. Main "fuel pump" relay was replaced, both sides pull in when cranking. I have a very mediocre Haynes manual with just about enough schematic to get me in trouble. I've checked the fuse by the coil, none blown or discolored in the fuse block, all wiring appears decent. I made a new harness for the underbelly fuel pump as the insulation on it had disintegrated... as stated, good fuel pressure, just nothing out of the injectors. I really want to get this survivor running!

(might confirm it will still fire on ether... that test was 4 years ago!) Just confirmed it will still fire on starting fluid...

 

You have connected a fuel pressure gauge to the injector rail ( with the weird adapter needed for a Volvo of that age?)

With your noid light - are the injectors firing?

If you don't think so you can pull the injector rail with feed and return hoses connected, lay it on top of the valve cover and watch the injectors spray -

If the injectors are firing - what are they spraying (after xx years) from the gas tank?

 

I have not "noided" the injector circuit, but have assembled the rail and injectors off the head, and nothing sprayed while cranking. The entire fuel system from tank to rail is new; tank, sender & pump, belly pump and filter, nylon fuel line to rail. I have a ton of fuel spilling when I pull an injector, and left the return line off long enough to purge the old brown stuff, so I have assumed the new parts are working. (yes, I know what happens next...) I can check the pressure, bought an expensive kit on Amazon a while back... but I'm pretty confident it'll prove the pressure is correct. I opened the ECU, solder joints aren't lovely, but don't appear to have failed. I might replace the 2 electrolytic caps on it and reflow all the joints just to be sure.

p.s. "noid" light is simply a suitable bulb or LED indicator in parallel with the injector circuit?

 

Pressure test would be a good first start

Those ecu's only fail (with some cars/part numbers) by failing to turn on the fuel pump. But not with a 1985 - that happened beginning with late 1980's speed sensor cars. (lh2.4?)

Noid lights can be from $5 to $xx for a kit.

 

If you have fuel pressure at the rails and if the engine starts on starting fluid then you need to check both the injector voltage and the injectors. The noid test will ell you if the injector circuit is working . Being the car has been sitting I would pull the injectors and have them cleaned or replaced. It all depends on the signal being at the injectors.

 

Doesn't sound like the injectors are firing at all so I would chase the problem from there. For a 1985 the pulse for the injectors comes from the hall sensor in the distributor. Google volvo 240 hall sensor and you will see all kinds of hits on it. Also, the 1985 model falls right in the middle of the years where wiring harness was made with biodegradable material which causes all sorts of electrical gremlins.

 

Will check injector signal today. Some harness' were replaced according to dealer receipts, the main engine harness looks very good, though there is some failed insulation on wires that look to go to the lights or horn. Would I have ignition if the hall sensor wasn't working? (Starts on ether) Thanks to all for the assist!

 

The hall sensor signal is used for both ignition and fuel system. It’s not your hall sensor if you have spark at the correct time

 

So I used a LED indicator light connected to the injector circuit, no blinking at all. I confirmed I have 12V at I believe terminal 1 on the ECU with ignition on, and various voltages on several other pins. Haynes decided no one cared about engine management by 1985 in the wiring diagrams they included in my manual... horn circuit made the cut though! The link posted above for manuals had nothing for a 1985 240 series.

 

So I guess I'm an idiot. I finally looked at the injector pulse with a scope and it's there. That gave me the idea to clean the injectors, not sure why I never tried that given the schmutz that was all the way through the fuel system. After cooking them in an ultrasonic cleaner and installing new o-rings and pintle caps, she's finally running. Not especially well, the car sat in Phoenix not running for about 5 years, so vacuum hoses are pretty crummy. It didn't really want to idle, and I had no brake boost, the end cap is missing from the check valve in the booster vacuum circuit, so I have one on order. Thanks for all the suggestions!