The mystery of my missing engine.

[rennch]

Compelling title, eh? "Wait...is the ENGINE missing? Like...it's not there anymore?"

No, not exactly.

It appears as if 1, if not 2 of my cylinders is not firing. "A dead hole", as they say.

First things first: Motor is a Euro 3.0 Carrera case, with mostly early engine bolt ons. (smaller distributor, etc...)

It has, at some point since I've had it, run brilliantly.

Important info:

MSD ignition and Coil.
New Battery

New Beru Wires, New Bosch Spark Plugs, New Cap & New Rotor

Injectors tested: They are all equal, and spray pattern is perfect.

Weak spark in cylinders 2 and 3.

Plug wiring is correct

My next thought was perhaps to change out the distributor if I can find a spare somewhere.

I've been told by Steve Grosekemper (Deiter's) and Marc Kinneger (Black Forest Automotive) that it's at least one cylinder down under load.

Can anyone help solve this mystery?

[pete3799]

I'd do a compression test to see if they're all healthy first.

[ivangene]

and a leakdown

[ivangene]

how did you measure "weak spark in 2-3"

[rennch]

Originally Posted by ivangene

how did you measure "weak spark in 2-3"

pulled a wire, plugged a spare plug in, and cranked the motor

[rennch]

Originally Posted by pete3799

I'd do a compression test to see if they're all healthy first.

Good idea...haven't done that yet.

I don't have a compression tester yet, so I'll have to grab one.

[ivangene]

Originally Posted by emptyo

pulled a wire, plugged a spare plug in, and cranked the motor

so it "looked" weak compared to others....

not a good measure - the only reason for that would be a wire, or a plug - but its not a good measurement

RE compression tester - I bet someone near you who has one would loan it to you for a couple beers
I would

[T77911S]

you may be confusing weak spark with just a weak cylinder based on what the 2 guys told you.
is it an idle issue or are you down on power driving?

compression and leak down test are needed.
i saw your fuel test. you might consider going back and doing it again if the teat above looks good. next time, fill the bottles at least half way, the more the better. do it WOT.

not the dist.

you could start it cold and check the temps of the exhaust at the exhaust ports to see if you have one not firing.

you also need to check timing. are you getting full advance?
check mixture.
air leaks
how do the plugs look?
fuel pressure- system pressure. fuel volume


not knowing what the engine is really doing i have to throw out the basics to cover it all. again, based on "one cylinder down under load" tells me its a driving issue. is this a WOT problem?

[rennch]

I got a compression test kit yesterday. Am hoping to find time to run it today. I've never done one before, so I'm hoping I'll do it right.

[rennch]

So, I was digging a bit further into the Pertronix situation, and I found this wire very frayed. It had been rubbing on the inner rotating cylinder of the distributor:



I cut it and patched the area. (I ordered a new Ignitor II yesterday, but I wanted to see if it would make a difference)

So...I went to start the car, and something very strange happened.

In the key "on" position, I got fuel pump, dash lights, etc.

When I turned it to fire the engine, everything abruptly cut out. I have nothing...no electrical whatsoever now.

I was able to reproduce it, but it's intermittent. and I can't start the car at all now.

Ugh.

Now what???

[Dave Colangelo]

My guess as to your electrical issue is that when patching it you left something exposed and the coil grounded though that point into your electrical system, check your fuses. Also check your bat connections and make sure they are secure. How exactly did you patch up the bad section of wire?

Regards
Dave

[rennch]

Originally Posted by Dave Colangelo

My guess as to your electrical issue is that when patching it you left something exposed and the coil grounded though that point into your electrical system, check your fuses. Also check your bat connections and make sure they are secure. How exactly did you patch up the bad section of wire?

Regards
Dave

I checked the fuses. It's intermittent...so tough to find.

to patch it, I cut it and put a male and female connector on it.

[gtc]

Do you have a set of points you can swap in to check the pertronix?

[rennch]

I don't. I wish I did.

[Dave Colangelo]

I have had a lot of success with electronic issues by just cleaning up the grounds and swapping all the fuses out. When doing so I clean up the fuse tabs until they are clean copper. There may be some rouge corrosion in there somewhere.

Regards
Dave

[rennch]

This is a problem that didn't exist before today though. And I've been messing with my wiring in the engine compartment. I feel like I had to have unplugged something or some such.