I posted a message few post down.My 1990 240dl stop running today.I bypassed the fuel pump relay and the car started just fine. I replaced the relay with a known good one and all was ok. Now the car won't start again. This time when I tried to bypass the relay the car still would not start. 25 amp fuse ok.Replaced with another good relay,no start.Put everything back together and unplugged amm,no start.What else should I check,need to move car in 24 hours.
Thanks for all ideas,
Nelson

If both the pumps are buzzing the problem may be the tube that conects the in tank fuel pump to the pump. It may come of and not run at all or in a way that when the tank is full some gas goes in and it runs but around half tank it hesitate or dies intermitenttly.
Good luck

Been following this thread, when my hose from the intank pump was shot, car ran only on full to 3/4 full tanks of gas.
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1985 240 DL, 1989 245 DL

you said you bypassed the relay but you didnt say if the pump was pumping. when you bypass the relay, does the pump start to buzz? if not maybe you have a bad fuel pump. if you gently tap on the pump while you crank the motor does it start to buzz?

I could not hear the pumps because of the cars whizzing by.I will go back in the early morning to see if I can hear them.Does one failing relay equate to a failed pump? Or is just not a good day for the volvo?

no, but fuel pumps on this model are commonly intermittent so it could work one day and not the next. if the pump has the undercoating spray on it you know it is the original pump,so if it is the original its 15 years old.

Great!Too late try anything tonight. Will try again in the am. Will also call FCP and get a new pump or two[ 87 a bit noisy].Gee I hope it just cools down and starts.Thanks,
Nelson

Check if you get good white spark on one of the sparkplugs. If you get no spark then there is a problem with the distributor hall effect sensor or ignition ECU

Check if you get fuel ok. If you can check for the correct pressure that will be great.

Is there anything that can be done to hot wire an ecu so I can get this car homeThis car has the 561 ecu. I have a spare 544 from my 87. Will this at least get me home,25 miles?

Is there anything that can be done to hot wire an ecu so I can get this car home?

If the 561 ecu is failing to ground the fuel relay for running (I believe this is the usual 561 problem), you can run a ground jumper to relay terminal 86/2 -- "back-probe" it in at the harness plug (Blue-Green wire).

Pump should run immediately with key ON.

P.S. I know of no basis for branding these pumps as "commonly intermittent".
What is relatively common here are known problems with fuel relay/ecu, fuse 6, the original rpm sender, aging AMMs, etc. And these things are only common here because this is a "trouble forum", and is thus not typical of all 240s.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

RPM sensor new,also the amm and fuel pump relay. It is looking more like a pump problem. When by passing the relay and jumpimg the pumps,no sound.Will probe the pump for current.Thanks
Nelson

Yeah, unfortunately the car needs a 561 or a 951 to run. The older (LH2.2) ones won't work.

Try these things:

1) check for spark. I pull off the coil wire at the dist, tuck it in by the left hood hinge and crank. I can see the end of the wire while I crank it myself that way. Good regular spark tells you that your crank sensor is OK. (No hall sensor on this later car). No spark, plan on getting it towed for a crank sensor replacement.

2) unplug the Air Mass Meter (AMM) in the LF fender area. 6-pin plug to it. Do this with the key off. If the car starts, GENTLY drive home, no heavy throttle or it's likely to stall. Plan on a new AMM in the morning. (Rebuilts are junk IMHO, likely to fail again.)

3) still no start, check the cam: have someone crank it while you look in the oil cap. No rotation = broken timing belt. Plan on having it towed. The belts can actually look OK even if damaged- sometimes they strip teeth off around the crank pulley and it turns but won't run the cam and dist.

4) beyond that, you will probably have to get into the ECU or a fuel pump. Yes, main pumps do fail and sometimes (rarely in my exp) they will RUN but not pump. I've only seen this with non-Bosch main pumps. Either way, maybe get it towed to somewhere more hospitable.... though I did a main pump right on a side road here in CT last year for someone. I don't recommend it, put it that way!

Good luck!
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Rob Bareiss, New London CT ::: Roterande Fläkt Och Drivremmar!

CPS test ok for spark. Can't test amm.Will check fuel pump later. Car is now at home in driveway!As for check engine light being on during cranking,yes. So I think the ecu is ok and the pump crapped out. Will post with my findings,Thanks to all,
Nelson

Crank sensor new,maybe 6 months,amm new 8 months, cam rotates, belt replaced last year.I did try the amm test,unplug and try to start,but no luck.I have tried 2 other known "good' relays but no start. I will resolder the original just because.I do have spark.So it is looking more like a fuel pump problem,I hope and not an ecu fiasco.Now to recharge the battery on my 87.Been sleeping most of the winter but that is another project.
Nelson

Run two wires directly from Battery to Pump. Pump it label "+" and "-"

If no run then you know. no more variables in the line from battery to Pump.
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me

Good idea. Will try it tomorrow.Losing to much time from work right now. I am 98% sure it is the fuel pump.New one on the way.Thanks,
Nelson

Those ECU's are not compatible. Look for a 951. Dan