B6 has no spark at ignition coil...

[Polonius]

I use the car pretty much only to commute in the winter (motorcyclist). I do drive it almost once a week or so in the summer, though. It's pretty much stock, has 169,000 km on it, and hasn't had the greatest maintenance, I'm sure. I picked it up one year ago.

It started dying on me about two months ago, but didn't do it again for about a month. It then didn't do it again for a couple weeks, etc, etc. Today it died many times in a row, and I think I'm not able to diagnose it any better than a few months ago.

So what happens is that whatever I'm doing, one of the first things I notice is the tach drops to 0. I could be idling at a light, cruising down the highway, accelerating, decelerating, anything. It's happened in all four circumstances. At idling, it just dies like you'd expect a car to die. Cruising and decelerating is a bit eerie though. Tach hits 0, there's no power. Car coasts ok, I'd originally thought that I could roll-start it back up just by leaving the clutch alone and letting the wheels start it again. This worked on the highway with all that momentum, but not in the city. On the highway, it did it again once or twice, and was fine after that. In the city, it wouldn't start up again before I'd stopped. I could immediately try starting it again, and everything seemed fine. Except that nothing would fire. I could keep trying (or not) for a few minutes, and eventually it would start again, and I could go.

Today, it died 10 seconds after starting again - 3 times in a row. And then tried twice later. Fortunately, hard acceleration seems to only allow a big jerk before it quits trying to die.

I pretty much always listen to music in the car (aftermarket deck, but no amps - until today. Put my sub in. It's pretty basic, though - nothing to big). The music doesn't stop when it dies, so I'm not sure if it's electronics.

I had originally thought it might be electronic, because the tach drops to 0 while the engine is still turning (from the wheels).

I've got new plugs, which I'm pretty sure I gapped before putting in. I've got full compression on 3 cylinders, but only 60 psi on one of them. It idles roughly, but not too bad. Runs ok at regular RPM, basically (not that I've ever had it with all 4 cylinders). I've got no dummy lights on when she's running. The only thing I can think of is that it doesn't do it on my 10 minute commute. Just when I'm running around picking stuff up, etc. So maybe being fully warmed up triggers the problem? Also, I noticed on another thread a guy's car is doing white smoke clouds on cold starts. Mine does that too, for a while. Can't remember what it smells like, but it's very white. And by cold, I mean right around freezing. Oh, and every time I open my gas cap there's a big in-rush of air. Is it supposed to turn into a vacuum in there? I'm not sure what my fuel level has been in the past, but today it was empty for half of the problem, and refilled for another couple of times.

So, I'm not really sure where to start. Now that it's had time to cool down, I'll take a look at some things like coolant level, oil level, airbox.... But I'm pretty novice, so it's basically just visual checks. Any pointers?

[Polonius]

Huh. Didn't realise I've never posted on here. I've been lurking for a year! So, uh... hi!

Also, it's a '93.

[Polonius]

Well, coolant is at a fine level, ditto with oil. Spark plugs look a nice healthy light brown, plus a black ring at the edge. Gap is right at 1.03 mm. Air filter is pretty good. There's a bit of something almost oily looking in the air pipe just inside from the filter, but I think that's normal case blowoff (or whatever you call it. Bikes usually have some from the crankcase, and this car looks like it has a breather tube going to the top of the valve cover).

So yeah, I'm still clueless.

[Polonius]

Oh crap. Just went to go drive a friend to work. Got out of the driveway, died. Wouldn't start. Still won't start. Fuel Inj relay clicks on ignition like it's supposed to. Aren't the injectors supposed to get DC voltage when the engine is running (and being started)? Because they aren't, and I don't know for sure...... An hour later, and she's still dead as a doornail. Had to have my wife help push it up the driveway. Try again tomorrow, I guess.

[Ryan]

Some easy things to check..

#1 is battery terminals. take them off, clean them, and tighten them down.

Thats probably it.

[Polonius]

Thanks for the reply!

No, it isn't them. I checked 'em over when I was doing power for the sub. They look great. Also, The starter keeps on turning like an Energizer bunny. In the best of ways (lots of battery power still, and solid enough connection to keep cranking reliably.)

I'm starting to wonder if it's an electronic problem in the fuel delivery? I don't know.....

[Ryan]

You're right my bad, I failed to read your post thoroughly.

Crank and no start is either fuel or spark issue. If its air, it would studder and stall but still try.

Easiest way to check the pump is to jump F/P and GND in the DIAG box under the hood, and then turn the key to 'on' . You should clearly hear the pump. If you're not sure, go over to the diag box and pull the jumper, and reinsert it and listen for the difference. It should be obvious.

Spark... just pull a plug wire and hold it close to a ground. It should jump from the empty end of the wire, a few mm's to a ground. Try coil wire and plug wire.

[Polonius]

Thanks again, Ryan.

Fuel pump makes normal(?) sounding noise when I check it that way.

Wire going to the distributor cap from the ignition coil(?) does not spark when held near ground (strut mounting bolts). I'm about to look through the manuals regarding the coil, but figured I'd stop to "check in".

[Ryan]

If you aren't getting spark, either the ignition system is toast somewhere, or it isn't getting signal.

Either take off the cap to see the rotor spin when cranking, or peel the timing covers back to make sure the cam is moving and the timing belt isn't broken.

There will be procedures in the online manual for how to test the ignition system.

[Polonius]

Woohoo!

I discovered that the connection of the wire (that goes to the dist. cap) to the ignition coil was iffy. Wiggled it a big to drive it in as tight as I could, and she's started perfectly a couple of times now!

Although, when I checked the primary coil it had no resistance at all. The secondary coil had about 12 ohms, which the manual says is fine (10-16). It might be my multimeter though, because I just have the cheap pocket analog one at home. But it's working now, anyway.

And the injector electrical connectors do indeed have voltage, I just needed to push my multimeter probes in further.

[Polonius]

Sigh......

Apparently, that wasn't it. It died more. I replaced the ignition coil, hoping it was the problem, but it still dies! I still get no spark out of the ignition coil when I crank, so I'll have to follow the path backwards some more tomorrow....

[Polonius]

Well, I get the 12V at the ignition coil connector like the manual says I'm supposed to. I can't check the ignitor because I don't have that SST thing, and I'm not quite sure where it is. I don't want to tow it to a shop 'cause I'm cheap, but I'm not sure what else to check.....

Sheesh. I left a connector unplugged from the injection manifold (?), so I plugged it in. Car started! Woohoo! Drove around the block, and it tried to die momentarily halfway. Then, just before I got back it died and wouldn't start. Dead as a doornail again.

Is it possible that there's a fuel issue involved, and my ignition coil not sparking is dependent on it? Or is the ignition coil not sparking a definitive electrical issue? Also, I can't find my ECU to even check the connections.

[Polonius]

Whoops, just noticed some stuff you told me to check, Ryan. Timing belt seems ok, as the distributor rotor does turn with the engine.

Third time through the ignition section of the manual - I suppose I should communicate my findings, eh?

So, I get my 12V at the connector on the ignition coil. But no spark out of the high tension lead that goes to the distributor. Brand new ignition coil.
I don't have the tools to check advance timing (which probably isn't the problem), or the ignitor.
Distributor cap & rotor look ok. I have an alternative set that also looks ok, but don't fix the problem either.
Distributor connector is ok, but I can't find the ECU to check the other end.
Ignitor connector gets 12V as per manual.

Oh sheesh. It started again. We'll see, I guess......

[Polonius]

Well, it stayed running for 10 minutes of driving around the block. Started every time without any trouble. I check the spark off the ignition coil, and it was mostly orange with a little blue. The manual says it should be a strong blue spark.