No spark

[Eric Wettschreck]

2000 Olds Bravada with a 4.3 motor.

It ran great yesterday. The wife got in it this morning and it wouldn't start. It has been raining and blowing hard all night so I thought the ignition was wet.

When I got home from work I shoved it into the garage and pulled the dist cap. It's bone dry. The cap and rotor definately look like they need replacing as they're showing their age, but no moisture. Cleaned things up, put back together, tried to start, still no spark.

Do ignition modules normally go bad when you shut the motor off??

I'm thinkin the module went bad. What do yous guys think?

[Macgyver55]

Did you check for spark at the coil wire or at a plug wire?

I've run into bad rotors and caps that are grounding internally so you wont see the spark unless you check it at the coil.

[Eric Wettschreck]

I did not check it at the coil. I pulled a plug and checked for spark there.

If the module is good it will spark at the coil, correct?

[Macgyver55]

Yup!

[Eric Wettschreck]

be right back.

[Eric Wettschreck]

Checked at the coil. There is spark at the coil. Checked at 3 different plugs, no spark.

Safe to assume then that the module is good, and the problem probably lies in the cap/rotor?

I've had bad caps and rotors before, but I've never heard of them going bad just at the snap of a finger. Then again, I'm not ASE type dude either, just a shade tree guy.

[Macgyver55]

Thats where I would go. Wet and damp weather brings out the worst in ignition systems. I guess if mileage/time warrants it, I'd replace the plugs and wires too. Hopefully that will get you back on the road.

[Jeremy airjer W]

Have fun whith the #5 plug if you choose to accept the challenge!

[Eric Wettschreck]

Have fun whith the #5 plug if you choose to accept the challenge!

I hate this rig. I'm thinking a black and red for sale sign is the best part I can buy.

I just put new plugs in this thing like 5000 miles or so ago. Don't let #5 feel so special, they all sucked.

[Macgyver55]

I just put new plugs in this thing like 5000 miles or so ago. Don't let #5 feel so special, they all sucked.

If you just did them, then the hard part is over Start with the cap and rotor and go from there.

[Eric Wettschreck]

That's the plan.

Thanks a bunch, Mac.

[dabaer]

i got a 4.3 in my s10, last summer on the rainy day i tried to start it and it wouldnt fire, next day i took off the cap and rotor both were dry, but there was corrision all over them cleaned them off put it back in and it did start but it struggled, replaced both of them and started great!!

[Eric Wettschreck]

I got home from work today and put in a cap and rotor. She started right up. That's the good news.

It runs horrible, idles rough, and no power. That's the bad news.

I hooked up my auto x-ray and got the code 0300- multiple cylinder misfire. I then took plug wires off the cap one at a time and yup, #1 and #5 have no change when I pulled off the plug wire. I pulled #1 plug, hooked it up to the wire, touched it to the manifold and started the motor. It's sparking. I didn't do the same to #5 because as airjer stated, it's a challenge.

This thing ran fine 2 days ago and now this. First no spark and no start. I fixed that but now #1 and #5 have no change with the plug wire disconnected, but #1 plug is firing and the piston will blow your finger off the open plug hole.

Any suggestions where to go from here?????

[Dozer]

Are you sure the wires are hooked up in the right order?

[Eric Wettschreck]

Yes. I checked, double checked, and triple checked.

[Jeremy airjer W]

3 2

1 4

5 6

- C

Are you sure the rotor is on the right way?

[Jeremy airjer W]

[Eric Wettschreck]

Rotors on the right way. I tried to put it on 180 off and it will only go on one way. Wires are on the right way.

Your last post is spot on, Jer.

[Jeremy airjer W]

Your sure the wires aren't arcing?

[Eric Wettschreck]

I can't see or hear anything arcing. This of course doesn't mean they arn't, I just can't see or hear it.

[Macgyver55]

Just for fun, humor me/us and quadruple check. Are you sure the cylinder positions are where you believe them to be? Did you trace each wire all the way to each plug to make sure that two are not crossed?

It just seems too coincidental that it was running fine before and now its missing after a cap and rotor install.

The cylinders are Drivers side front to rear 1..3..5 and passenger side front to back 2..4..6.

[Eric Wettschreck]

Mac, you wouldn't believe how many times I've traced them out. The wires are on the right part of the cap.

I've taken this cap and rotor off about a million times now and still no change. I know it's very weird that things were good, then no spark, cap and rotor later and I have a misfire.

I don't have time to work on this as life is getting busy. It's on it's way to my good friend Jimmy (ASE tech) at his shop when I get home from work.

I'll let yous guys know what the deal was when I get it back.

[Surface Tension]

Eric did you plug the wires from the plugs?

Any chance you didn't get them seated?

I had the runs rough in wet weather syndrome on the van.

Of coarse the first thing I did was change the cap/rotor/wires.

Didn't do a thing. Eventually I found out water was running off the windshield and onto the engine. Guess where some of that water ended up? Yep wet spark plugs and it would sit there till you drove long enough. I pulled off the weather striping and used contact cement to reattach it. Problem solved.

That could be your problem. If you didn't drop off yet, use compressed air the blow out any water that could have gotten around your plugs. Remove the plug wire and dry that out too. It'll take a lot of air directly at the source so use a hose off your air tool to get down in there.

[IFallsRon]

I had a beater that the ECM went out. No spark.

[Eric Wettschreck]

Jimmy told me there are 2 bad injectors. We'll see how this POS runs after they're replaced.