Hello all, having some issues with my '83 240, running a B23. Car was running fine previous to this. Just started up the other day, put it into reverse, began backing up, and it died. Would not start again.

Here are the symptoms:
- Will not start. Turns over and over but does not catch, and I don't hear it even trying to.

My troubleshooting steps:
1. Checked fuel pumps - jumpered them and the both sound fine, no whine, just a good solid whir. Tried cranking with pumps jumped, no change.

2. Checked intake piping - no vac leaks that I can see.

3. Checked wiring - all connectors firmly in place, all grounds connected and tight (block to batt, intake to block, system grounds to intake, all good). The wiring harness was rebuilt by myself over 3k mi ago with new Volvo wires, everything that was degraded was replaced completely to the connectors).

4. Checked for spark at coil, distributor, and plugs, all good.

5. Pulled plugs - no fouling, gaps good, spark fine outside of the block.

6. Let the block dry out for 4 hours with the plugs out, reinstalled. No change.

7. Pulled the connector off the Coolant Temp Sender (to the ECU). Noticed that one of the pins was pushed back in the connector. Realigned and reconnected by pressing on the wires to ensure complete contact. No change.

8. Tried starting with starting fluid, however, left the injectors connected, so possibly the engine flooded. Did not get any start on starting fluid.

The only thing I can think of is that the temp sender has failed and is flooding the motor. The only other caveat is that I filled up with a full tank prior to parking the car, it has not run since. However, I've never seen bad gas that will not ignite AT ALL. I get a good smell of gasoline while I had the plugs removed.

Any thoughts or troubleshooting tips would be appreciated. I'm going to go down and try starting now with started fluid and injectors disconnected to see if I get anything.

-Phil

Here's some updated troubleshooting, still stuck.

1. Swapped injectors.
2. New coil
3. New plug wires
3. Clean and regap plugs
4. Verify strong spark at plugs
5. New distributor cap
6. Checked fuel deliver volume, correct.
7. Swapped known-good fuel pressure regulator.

At this point, I think the issue is either fuel pressure or bad gas. Is it possible for excessive cranking to kill an FPR? When pulling the vac line, I can smell gas on that side (in the vac line).

-Phil

I once found a car that ran fine with a FPR sending gas through its vacuum hose into the intake manifold. Does the vacuum hose on it have any fuel smell or is there fuel coming out of it?

What about the 25 amp fuse? I've seen one get wet/dirty to where it was making the car turn over with no start.

Just thought I'd shoot this down the old intake an see what happens. Have you checked the timing belt.

RonJ

Timing belt is ~3k old, new tensioner. I will check that as well, but I don't think that's it.

Thanks for the tip.

-Phil

Well at this point the crankcase is pretty much filled with gas - I guess that answers my question as to whether or not the engine was flooding. I can feel and smell a gas film most of the way up the dipstick. I've left the oil cap off in hopes that it might air out - is this reasonable or should I just have it towed to my garage and empty out the oil?

-Phil

Hi Phil,

Missed your post here for some reason and found it on TB.

"An open ECT will flood the motor in any climate outside of Nome, AK. You'll have fuel in the crankcase, and the cylinders will be washed with fuel to the point you haven't got enough compression to fire once you do correct the rich mixture."

"To verify your ECT is the cause, given you know how well you made the harness, go to ECU pin 2, and measure to ground. Compare the resistance reading to the temperature chart in your garage manual. If all looks well, consider it may be intermittent. If you backprobe pin 2, the voltage will vary from about 2.2V at 68F down to less than half a volt as the motor warms up to operating temp."

I should have added the suggestion to put some oil in each plug hole to re-establish compression, once you've solved the flooding.


--
Art Benstein near Baltimore

Drive-In banks were established so most of the cars today could see their real owners. (E. Joseph Cossman)

Thanks Art. I have a spare sensor and will put that in. I will also try the oil trick - how much should I put in each cyl? Once I get it running, is it OK to drive 20 mi to my garage to change the oil or should I take it to a local quick lube place (grrrrr)?

-Phil

Hi Phil,

Given California's clement weather, why not get that electrical test under your belt instead of jumping ahead to the part swap? What if, indeed, the connector has been pushed back? How will swapping the sensor help find that? It is very easy and comfortable to finish the diagnosis sitting on the passenger's door sill with the ECU in your hand. If you decide to swap the sensor, I've done this only removing the AMM and flame trap hose, giving room for a deep well 19mm socket and 10" 3/8 drive extension. Very little coolant leaks out while you are swapping.

Whether you drive with a mix of oil and gas in the crankcase, has to be your call. Only you know how much fuel is in there. I'd be more worried about bearings than blowing the oil pan off, but how much trouble could it be to drain and refill the oil where it sits?

Returning lube to the cylinder walls doesn't take that much oil. I envision it as less than a teaspoon per cylinder, and would equate that to about 2/3 of a pull on this old oil can. Cranking for a couple seconds should distribute it well enough.


--
Art Benstein near Baltimore

Be thankful for problems. If they were less difficult, someone with less ability might have your job.

Are you getting spark?

Not sure if this works on an 83 but will it start with the AMM disconnected? (key off)

Change the oil, if there is a lot of gas in the oil and went down the cylinders compression is down to the point it won't start. Put an ounce of oil in each cylinder for compression, clean or change plugs

Dan

Try some NGK plugs if you don't have them in there now.I had BOSCH plugs in mine and it failed to start on very cold days.The NGKS would fire where others won't.My car is a 83 240 also,B23.This fuel system doesn't use a cold start valve so it injects extra hard on cold days.The NGKS will fire in richer conditions.Try it.

That's a good idea - I think I might have some sitting around. I've always preferred NGK anyways.

-Phil