Need help with no spark

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krazykuda

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Hi guys, we just got the new engine in the car and rewired the alt - ballast- coil, & ignition box with new wires and correct wiring diagrams (I hope...)...

We are not getting spark out of the coil. It's a new MSD Blaster 2, we have a MP chrome box from Jeggs, and the plug and play modified distributor with the advance limiting plate from the forum member here.

With a test light I get power at the input and output of the ballast resistor. I also get power to the positive terminal on the coil. I also get power on the blue wire at the control box at the harness, and the black when it's disconnected.

I am also getting power to the electric choke that is wired to the input side of the ballast.

This is all tested with the clamp of the test light on the negative battery terminal.

We are getting 6 volts at the positive coil terminal, with 1 1/2 volts at the negative terminal, and 4 Volts from going from positive to negative across the coil.


It won't crank over by the key, but we have to turn the key to on and jump the starter relay to get it to turn over.

We also noticed when we turn the ignition key to off from run, we get one spark jumping off the coil center main wire to a ground (we have the center coil wire disconnected checking for spark). We don't get any spark jumping from the center coil wire to a ground when cranking with a remote starter with the key on.

How to we test the ignition box to make sure it's not causing the problem and what other tests can we do with the coil to see why we are not getting spark?

Thanks for any help and replies...
 
Park/neutral safety switch stopping you from turning it over by the key/killing the spark??
 
Ok so we know coil is producing a spark when you interrupt the power via key. Problem is narrowed to either no signal from the distributor or bad module or module / engine ground.... Also check reluctor gap with an 0.006 plastic or paper gauge and try reversing polarity on distributor connector.
 
I recently went through this with a friends car. We pulled the "NEW" aftermarket distributor and went with a known good OEM unit then had to swap out the new orange box for a used chrome one to get a good blue spark....
 
Do you have a ground strap from engine to firewall?
Yep he do.
You might try a temporary ground wire direct to the box.
From MP............

Ignition1.gif
 
Thanks for the replies guys. We will check these ideas out and get back with you...

I did a continuity test and am getting continuity from the control box to the battery negative (ground), but may try to run a separate wire from the box to a body ground...

We will also verify the reluctor gap...

I have a complete electronic conversion kit that we can use to swap parts for testing...
 
Do you have a ground strap from engine to firewall?

Yes, we have a real fat flat one from the pass rear bolt on the intake to the firewall. I also ran a 10 gauge wire coming off the negative battery terminal to body ground in the front radiator panel. So we should have good ground (I hope)....
 
To get started, make a few tests..........

With everything hooked up "normal" turn key to run

Measure power on both sides of ballast. "Key" side should be "same as battery" and coil side should be somewhat lower perhaps 8V

Measure power at coil NEG. Should be quite low, 1V or so

Wiggle and work the dist. connector in/ out several times

Make CERTAIN and I mean CERTAIN that the ECU is grounded.

Hook the disconnected distributor connector..........the dist end....to your voltmeter on low volts AC. That's right, AC. Crank the engine. It should produce about 1V AC

Remove cap and examine internally for junk, rust debri, or strike damage to reluctor

Get a brass feeler and measure reluctor to pickup gap, .008". That's inches, not metric

Turn the key to run. Hold the coil HT wire near ground. Separate the distributor connector, and take up the vehicle side (not the dist end). "Tap" the bare connector terminal to ground. You should get one spark "snap" each time

Disconnect "everything" to coil except coil + and NEG wires, unhook tach, radio condenser
 
To get started, make a few tests..........

With everything hooked up "normal" turn key to run

Measure power on both sides of ballast. "Key" side should be "same as battery" and coil side should be somewhat lower perhaps 8V

Measure power at coil NEG. Should be quite low, 1V or so

Wiggle and work the dist. connector in/ out several times

Make CERTAIN and I mean CERTAIN that the ECU is grounded.

Hook the disconnected distributor connector..........the dist end....to your voltmeter on low volts AC. That's right, AC. Crank the engine. It should produce about 1V AC

Remove cap and examine internally for junk, rust debri, or strike damage to reluctor

Get a brass feeler and measure reluctor to pickup gap, .008". That's inches, not metric

Turn the key to run. Hold the coil HT wire near ground. Separate the distributor connector, and take up the vehicle side (not the dist end). "Tap" the bare connector terminal to ground. You should get one spark "snap" each time

Disconnect "everything" to coil except coil + and NEG wires, unhook tach, radio condenser


Thanks for the reply Del.

Here's what we measured when following your directions:



Test 1 Test 2

Battery voltage: 12.9 v 10.5 v

Ballast in: 11 v 10.5 v
Ballast out: 4.3 v 4.5 v

Coil + 4.1 v 4.5 v
Coil - 1.2 v 1.75 v

Resistance from control box to body ground strap = 0 ohms and passes continuity test.

Test 1 data is from my tune up gauge...
Test 2 is from my multi meter (Old analog one...)...

*****************************************************************

We were playing around with the shifter and found that it won't crank in any position P-R-N-D-2-1
however when we turned the key to the start position in each gear we would get one spark from the coil center wire to ground when we went to "start/crank position", then nothing and the starter would not crank...


Could the ignition switch or neutral safety switch cause no spark if we are jumping across the starter relay??? should we get the car to crank with the key first, then see if it will start that way???

*******************************************************************

Also, we tried to disconnect the distributor wire and crank is as you described and could not measure any voltage on either AC or DC scale while cranking with remote starter...
 
I was curious about that....as the bay looks like a fresh coat of paint.

I was trying not to scrape any of the new paint off if I didn't have to and hope the bolt contact would suffice....

I did measure 0 ohms from the control box body to the body ground strap...
 
Oh, and BTW, no need to disturb the paint, clean a spot on the outside of the inner fender, use a small machine screw in that corner with a nut on the outside. Clean the one hole on the ECU where the screw goes through.
 
Park/neutral safety switch stopping you from turning it over by the key/killing the spark??

That could be possible. See my post above about trying to crank it in each gear (just to see what happens), after reading your post...
 
Seems to me if it were grounded you would 'want' to see continuity there.

You mis-understood.

I checked continuity and it "beeps" when I put the probes on it...

I then measured for resistance from the ignition box body to the body bolt of the ground strap and found 0 ohms resistance, which should indicate a good ground (no resistance should mean free flow..)... So I'm getting continuity with very little resistance, that should be good... (I think...)
 
Here's what we have for ground:

Ground strap from intake to body:


DSC05026 B.jpg


Battery negative going to front of driver's side head:

DSC05028 B.jpg


Here's the 10 gauge wire going to the header panel off the battery negative post:

DSC05030 B.jpg
 
Will that work, or can it mess up something???

You don't want to run it that way for long, just to see if it starts.

In looking at those grounds, you still may have issues. Is the spot on the head cleaned off? The firewall? The core support??
 
You don't want to run it that way for long, just to see if it starts.

In looking at those grounds, you still may have issues. Is the spot on the head cleaned off? The firewall? The core support??

No, the intake is powder coated and we didn't want to damage it...

No, we didn't clean off the spot on the head or intake, but we did chase all threads with a tap so the threads should be clean virgin metal...

I did wire brush the contact point for the body ground at the front header panel where the 10 gauge wire goes to...

Should we scrape paint off the contact patches???
 
Your using a p4120534 chrome box right?

Anyone, for the Neutral Start, can't the lead on the starter relay be jumped similar to a stick. Yeah, it would crank in any position, but just to try and isolate a problem.

Don't know if this hurts or helps. Installation points from the book ...........
Ignition1.gif

Ignition3.gif
 
I did wire brush the contact point for the body ground at the front header panel where the 10 gauge wire goes to...

Just for giggles, see if you have continuity from the ground strap on the firewall to the negative cable end, pull it off the battery. You should, if those two places are clean grounds, I would think.

I just went out and checked mine, I get a solid beep when checking the firewall ground strap the the battery negative cable (battery end).

This should tell you if you have good grounds.
 
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