'84 240 GL- Main fuel pump not working.........now no spark, bought new coil...

I have a 1984 Volvo 240 Series GL. It has an automatic/overdrive, EFI
(LH-Jetronic injector system) with the 2.3L B23F motor.

The other day I was going to go to the store, started the car and let
it warm up close to normal operating temperature before driving. I drove
about 2 block when it shut down for seemingly no reason. For the next 5
minutes I tried to restart it. At first it would fire, run for a moment
and then die, like it was starving for gas. It would fire and I would
pump the gas like crazy, but it wouldn’t have any effect, it still died
after a few moments, and I noticed it wouldn’t rev up above about
1200-1300 rpm. The last time it “ran” I fired it up and it briefly ran at
about 200-300 rpm before it died. Again, pumping the gas had no effect at
all. It ran as if it was running on fumes.

The following day I put 5 gallons of gas in it, tried to start it but
it only turned over, didn’t fire at all. I realized that I didn’t hear
the fuel pumps working when I tried to start it and suspected fuel pump
failure. After testing out the fuel system, per my Haynes manual, I
eventually put a jumper where the relay goes and found that the pumps
didn’t fail, that they were working fine and had fuel through-out the
fuel system, as it should be.

With the fuel system working (when I jump the relay) I discover, after
pulling a spark plug to check for spark, that I have no spark. Next, I
test the coil and the readings are below the low end of the tolerance
levels. After having a mechanic confirm my coil is bad, I installed a new
one but I still don't have spark.

This is what I know and what I have done:
· bought new and replaced relays and ignition coil
· removed a spark plug, grounded it, cranked the motor, no spark
· unplugged coil/cap wire from distributor, grounded it, cranked the
motor, no spark
· with key on, coil has 12v on both sides of the primary terminals (if
this is normal why does the coil have -1 and +15 markings on it)
· cap and rotor slightly worn, but not bad, with no moisture inside the
cap
· tested ignition control unit for voltage on the blue wire (#2 connector)
and it had 12v, then I tested the black wire/ground circuit (#10 connector)
and had 0.4 ohms resistance, within the 0.5 ohms or less tolerance.
· per manual, pick-up coil ok
I’m lost after this. I still can’t get a spark. Is there something I
missed that I need to check or something I should try? What is my next
step? This is my first time working with an electronic fuel injection
system, so I’m kind of stumbling through and could really use some help,
suggestions, do’s, don’ts or anything you may consider useful.

 

12V to both sides of the coil when not cranking or running is normal. As the
spark is called for, one side (I forget which) is momentarily grounded and
then opened again at the moment of spark. I think the high tension parts are
probably okay from the progression of your symptoms, but the ground never
comes. (A test across the terminals when you crank the engine can confirm
that.)

Perhaps you have lost power to the ECU. Dunno if this applies to 240s, but
it happened to my 760 and a couple of other 740/760 owners. The lead at the
positive terminal of the battery corroded and made intermittent or high
resistance contact. Kind of a long shot, but ensuring all the wires are
intact at the battery with a gentle tug is quick and easy. Mine came apart
when touched. In the 240 power may come from a different source, including a
regular fuse. I am not familiar.

In any event, wiring problems are a suspect because the fuel quit before the
spark did, and both are now dead. Does your 84 show signs of wiring rot
under the hood?

Mike

 

fwiw, I have an '83 with ~250 on the clock.
Owned it 7 years and it always starts second try. Bump the key once, bump it
again and it lites...
One morning I did the same as always and was sitting there warming up. After a
minute, the motor spins down and stops... just like someone clicked off the
key.
I spun it a couple times, not even a cough.
Put a light on it and it had spark so must be no fuel.
Being a lazy sort, I checked the easy things first. Fuses were good but a
little corrupted.
Cleaned the contacts and put new ones in.
It fired right up...

 

Also fwiw... that suggests the fuel pressure is bleeding off. Usually it is
the check valve on the fuel pump. But mine has done that, too, for a year or
so. It's hard to work up the initiative to do anything about it!

Mike

 

So, you're saying it should go first click?
I've always been tickled that it started so well... the second try.
We're not talking round and round either. I touch the key once, motor may go
half way around. Touch it again and it goes.
Other injected cars I've seen and driven grind, and grind, and grind before they
lite.
You're right about messing with it though. Other things need attention... like
the harness leprosy, heater valve, odo gear, etc.

 

Yep - the bump/start thing is the shadetree test for leaking off fuel
pressure. The first bump fires up the fuel pump, and the second hit lets the
engine start. If you don't bump it the engine will grind several seconds as
the injection system tries to figure out what's going on.

Mike

Mike

 

Exactly... Whenever anyone borrows my car, I cringe as they try to wear out the
starter.
Thanks for the insight.
Now I have an explanation (besides 'cause it works better this way) when I tell
them how to start it.

 

Those old 240s with the Chrysler ignition have a big problem with the
connector between the wiring harness and ignition computer (the box
mounted on the windshield washer bottle bracket). If that connector is
disconnected for any reason, the harness is supposed to be replaced!

Also, don't worry about the fuel pump not working - the fuel pump relay
doesn't turn on until it sees the low tension ignition pulse.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)