240: Brick died on hwy, won't start

[SaltyBrick_MN]

**Ignition Coil was grounding somewhere. unplugged wire going to the tachometer and she turned over! For anyone seeing this down the road, test for spark and work backward!**

SOS! Box Down, Box Down!
My ‘92 245 (LH 3.1, M47) stalled on me this weekend. I was going about 50 mph, and it just died- didn’t overheat nothing weird before this happened. Got it towed home, and I haven’t been able to start it since. I've been through the forums and read through the countless threads, where most issues were resolved by either the fuel pump relay, an inline 25A blade fuse off the battery, or the crankshaft position sensor.

I'm getting no error codes (1-1-1), and all the systems clicked on in sequence (injectors, IAC, etc.) The fuel pump relay is new and doing its thing (clicking with ignition turn); pumps are new and kicking on. As far as I have seen and confirmed on my year of box, there’s no 25A fuse off my battery. My crank position sensor was hanging by a thread, so I replaced it with an OEM Volvo part but still nothing. Just cranks...

Parts replaced last 2k miles:
- spark plugs, gapped to 0.028
- cap+rotor, plug wires, ignition coil,
- fuel pressure reg, pre+main pumps, filter, all 4 injectors/seals
- IAC valve, throttle switch, coolant temp sensor
- Crankshaft position sensor
- Timing belt, tensioner, harmonic balancer

The ignition module tested good but was replaced, to be sure. Air Mass Meter is testing good (112 ohms) and cleaned with the proper cleaner. All electrical connections I could find have been cleaned and dabbed with grease. Grounds have gotten the same treatment. Compression was tested, and everything is within spec. I pulled spark plugs and could smell gas. I'm alone in this pandemic and have no remote switch, so it was tough to monitor spark. However, I did rig something up, grounding the plug to the engine block and recorded with a camera. No spark. As mentioned, I replaced the coil with a Bosch unit, and it's been running great until this stall/no start.

My last test before I rage quit and take it in is the ECU. I read somewhere that a bad ECU was the culprit for one stall-no start, but that was a pink label ECU. My ECU is a Bosch 000 572 (AF).

Any ideas?? por favor!!

[2manyturbos]

The ECU has nothing to do with spark. It does need the spark signal in order to fire the injectors. It is kind of a one way street. The ECU needs the EZK. The opposite is not true. If you determine you do not have spark, check whether you are getting 12V at the coil with the key in the run position. You may have a bad ignition switch. The contacts do wear out.

[ZVOLV]

You can just make a jumper wire to the starter. Apply B+ from the battery and have key on.

Powerstage?

[RonJ]

Have you checked the timing belt.

RonJ

[SaltyBrick_MN]

Originally Posted by 2manyturbos

The ECU has nothing to do with spark. It does need the spark signal in order to fire the injectors. It is kind of a one way street. The ECU needs the EZK. The opposite is not true. If you determine you do not have spark, check whether you are getting 12V at the coil with the key in the run position. You may have a bad ignition switch. The contacts do wear out.

Okay.. thanks for the information, def good to know. Would a bag ignition switch cause it to die, while driving? I'll get the meter back out and verify the ignition coil is still testing good, and that it gets signal with key on. Thank you!

[SaltyBrick_MN]

Originally Posted by ZVOLV

You can just make a jumper wire to the starter. Apply B+ from the battery and have key on.

Powerstage?

Yep, power stage tested within spec but I still replaced it. And I've tried going back to the original part as well, bc aftermarket is the only available part I could find. I'll look at doing the process you outlined. Thanks!

[SaltyBrick_MN]

Originally Posted by RonJ

Have you checked the timing belt.

RonJ

Yessir, timing belt is still intact and the cam is still spinning. Did the timing belt over Christmas and left the cover off to repair the plastic bits. Never got around to getting it back on there so clear view atm.

[ZVOLV]

Do you have injector pulse?


Do you have a test lamp?

[bobxyz]

There should be a little unconnected single pink wire test socket in the engine compartment up against the bulkhead, roughly in the center. If you jumper this to battery +12v, it will crank the engine. It goes through the P/N interlock switch on Auto's, so it's a little safer and easier than jumpering the starter solenoid directly.

When you checked the codes after cranking, did you do both EZK and ECU (sockets 6 and 2)? Both 1-1-1?

[SaltyBrick_MN]

Originally Posted by ZVOLV

Do you have injector pulse?


Do you have a test lamp?

Yep, I'm getting injector pulse when running the diagnostic sequence. I don't have a test lamp, I'm guessing this is timing-related? Definitely something I should have on the shelf already.. I'll look into this.

[SaltyBrick_MN]

Originally Posted by bobxyz

When you checked the codes after cranking, did you do both EZK and ECU (sockets 6 and 2)? Both 1-1-1?

Ran both EZK and ECU, got 1-1-1 off ECU, and I everything clicked on in sequence (IAC, Injectors, etc.) The only component that I couldn't get on was my cold start injector, but I can't imagine this would be my cause for no start?

This all started with it dying at speed and then no start, so I have to imagine something got disconnected or grounded out?

[ZVOLV]

Click my signature.

Spark, fuel pressure, injector pulse, timing, compression. What's missing?

Injector pulse can be tested with a test lamp backprobed between an unplugged injector wiring connector.

[SaltyBrick_MN]

Originally Posted by ZVOLV

Click my signature.

Spark, fuel pressure, injector pulse, timing, compression. What's missing?

Injector pulse can be tested with a test lamp backprobed between an unplugged injector wiring connector.

Thanks for being so responsive friend!

I got her running this morning, it was in fact the coil grounding out.

Long story short, I bought the "large" tachometer with clock off ebay last year, and couldn't get it to function. The seller was adamant he replaced the internal bits and tested to make sure it was doing its thing. I assumed there was a splice somewhere in the red/white wire so I ran a new wire off the coil to the tach. Still wasn't getting a signal. This wire that I ran must've came loose and made contact somewhere behind the dash. In any case, unplugging this wire are the coil solved my issue of the coil grounding out.

I couldn't find the thread again, but there was a comment made by the infamous "Art" dude on another forum that got me thinking about that tach wire.

Thanks again to all that chimed in. No better feeling than getting something to run again!

[ZVOLV]

Good find. Thanks for posting back.