Ignition problem- New parts, no spark- 454 HEI

[suburble]

Hey, all. Finished replacing a bunch of tune-up parts on my '86 C20 Suburban but I'm still having problems. It's a 454 with HEI.

Here's the history:

It starting acting like it was missing a cylinder last Friday. When I tried to start it last Saturday it fired over and idled for a few seconds and then died. After that, no spark at all.

I pulled the cap and wires (pic below) and the rotor button was GONE, and some of the wires toasted to the point of crumbling.

I replaced the plugs, wires, cap, rotor, coil, Ignition module, and the Radio Noise suppressor part that plugs onto it.

It fired up and ran great for about a mile, then cut out completely. Once again, no spark. There was one more strange symptom- the windshield wiper ran intermittently for the first few minutes after I first started it up (this has not happened before).

The plug wires, rotor, contact button, etc. all looked fine. I went to the parts store and got ANOTHER coil, ignition module, and Radio Noise thingy under warranty. Still no dice. Parts all looked fine, no rattling in the coil or modules, no signs of arcing.

I spent about 4 hours playing mix-and match with various new parts and checking connections. I could not get it to fire once. It was turning over just fine, just no spark.

I had it towed home, tomorrow I will check if it's getting 12v at the coil.

The only 2 things I can think of are:
-It might have a short in the wiring going from the ignition switch to the coil, or a bad ignition switch
-The distributor pickup mounted under the advance weights might have somehow gone bad

Here's my questions:

Assuming it has 12v at the coil, is there anything else in the system I could check besides the distributor pickup?

If it does not have 12v at the coil, am I safe bypassing the ignition switch wiring by running a wire to the coil directly from the battery, for test purposes?

Should there be fuse, breaker, or fusible link anywhere in the ignition wiring?

Add'l information: All parts were BWD from O'reilly Auto Parts.

Pics are from the old parts I took off. None of the new parts look bad.

 

[HotRodPC]

You're aware this should be an ESC distributor? There is a way to bypass the ESC by cutting and twisting some wires at the dizzy. At that point it operates just like the old fashioned HEI dizzy. All the ESC does, is allow maximum ignition timing and when a knock is detected it retards the timing so the knock goes away. Do you know if you still have the ESC computer as part of this ignition system?

OH and yes, the Pick Up coil could have certainly gone bad too.

 

[suburble]

You're aware this should be an ESC distributor? There is a way to bypass the ESC by cutting and twisting some wires at the dizzy. At that point it operates just like the old fashioned HEI dizzy. All the ESC does, is allow maximum ignition timing and when a knock is detected it retards the timing so the knock goes away. Do you know if you still have the ESC computer as part of this ignition system?

OH and yes, the Pick Up coil could have certainly gone bad too.

Shouldn't the ESC dizzy have a plug-in instead of a vac advance? Mine definitely has vac advance. What would indicate if it should have originally had the ESC type?

 

[HotRodPC]

ESC also has Vac Advance. To tell the difference is to look at the plug on the dizzy. Let's see if someone might post up pics of the differences, or I'll look to see what I can find too.

 

[chengny]

The harness connector for an ESC enabled distributor has different configuration according to the year/make/model of the vehicle. This may be what goes on a 86-88 SBC with ESC - also shows the wiring modifications required to turn an ESC it into a standard HEI distributor:

You must be registered for see images attach

But all that does not matter if your harness connector looks like this:

You must be registered for see images attach

If it does (look like the above) you have a standard HEI distributor.

 

[chengny]

Should there be fuse, breaker, or fusible link anywhere in the ignition wiring?


As shown in the text above, the power from the battery has to go through the following to reach the primary side of the ignition coil:

1. Two different fusible links. One of them is down close to the starter (it might be a little bit up in the conduit tube that carries the wiring to and from the solenoid). The other is just a couple of inches away from the firewall junction block - the wire is connected to the JB.

2. The ignition switch. When the key is in the either the START or RUN position, the contacts that switch power on/off to the coil are closed. This allows current to flow to...

3. The neutral safety switch (or the clutch switch if it has a manual transmission). If the transmission is in either the P or N position the NSS contacts (CSS if MT) are closed and battery voltage is then available at the BAT terminal of the distributor (positive side of the coil primary). This is via the red wire. The white wire provides a signal to drive the tachometer if so equipped.


The image below shows the locations of the two fusible links - the location of the ignition switch and NSS should be apparent:

You must be registered for see images attach

 

[HotRodPC]

Yep, un huh, that's what I'm talking about. Thanks again Jerry.

 

[Jims86]

Ummmm....I dont think the BBs were esc. I may be wrong. in 86 for Ca the only esc or CC carb engines were in the 1/2 tons. 3/4 sbc and BB wer old school, no frills.

 

[chengny]

Ummmm....I dont think the BBs were esc. I may be wrong. in 86 for Ca the only esc or CC carb engines were in the 1/2 tons. 3/4 sbc and BB wer old school, no frills.

X2.

I find that BB's are set up externally just like the 350's that were installed in trucks with the EPA classification: "Federal - Heavy Duty Emissions Package" ( i.e. no cats, no o2 sensors, no carb controls, etc.)

Other than 2 air pumps, an evaporative emissions system and an EGR valve, they were basically bare bones engines).

 

[GTME94]

Ummmm....I dont think the BBs were esc. I may be wrong. in 86 for Ca the only esc or CC carb engines were in the 1/2 tons. 3/4 sbc and BB wer old school, no frills.

X2.

I find that BB's are set up externally just like the 350's that were installed in trucks with the EPA classification: "Federal - Heavy Duty Emissions Package" ( i.e. no cats, no o2 sensors, no carb controls, etc.)

Other than 2 air pumps, an evaporative emissions system and an EGR valve, they were basically bare bones engines).

That's how my '86 454 is. I'm not sure it even has EGR, or maybe it was removed before I got it. I removed the AIR and evap.

 

[suburble]

Wish I'd grabbed some pics of the harness connectors while I was under the hood earlier, but here goes:

There are 2 connectors that plug into the distributor cap.

The one closest to the distributor body comes up from the "Radio Frequency Interference Condenser" inside the distributor, which is plugged into the ignition module. It has 3 wires.

The one further out from the distributor comes up from the firewall, and has 2 wires.

I'm assuming the 2-wire connector from the firewall is keyed 12v for the coil, and should show 12v across the 2 terminals when they key is at "start" or "run".

When I measured across those 2 terminals (with my wife inside the 'burb turning the key) I saw a small jump to about 1.5v when the key was first turned, then nothing.

Am I correct in thinking I should be seeing 12v?

 

[HotRodPC]

Ummmm....I dont think the BBs were esc. I may be wrong. in 86 for Ca the only esc or CC carb engines were in the 1/2 tons. 3/4 sbc and BB wer old school, no frills.

You could be right, but pretty sure my 86 C20 is CCC and does have a ECM with knock sensor. Did have a feedback carb, but it's got a non feedback card on it now, and a standard HEI Dizzy. The wires are all there though.

 

[suburble]

Should there be fuse, breaker, or fusible link anywhere in the ignition wiring?


As shown in the text above, the power from the battery has to go through the following to reach the primary side of the ignition coil:

1. Two different fusible links. One of them is down close to the starter (it might be a little bit up in the conduit tube that carries the wiring to and from the solenoid). The other is just a couple of inches away from the firewall junction block - the wire is connected to the JB.

2. The ignition switch. When the key is in the either the START or RUN position, the contacts that switch power on/off to the coil are closed. This allows current to flow to...

3. The neutral safety switch (or the clutch switch if it has a manual transmission). If the transmission is in either the P or N position the NSS contacts (CSS if MT) are closed and battery voltage is then available at the BAT terminal of the distributor (positive side of the coil primary). This is via the red wire. The white wire provides a signal to drive the tachometer if so equipped.


The image below shows the locations of the two fusible links - the location of the ignition switch and NSS should be apparent:

You must be registered for see images attach

Thanks, this is very helpful.

So, check me on this logic:

-Neutral safety switch is not the problem per functional testing; the starter turns the motor over just fine in P or N, but not in gear.

-Fusible link between starter and battery is not the problem per above

So... If I'm correct in assuming I should be seeing 12v at the plug in from the firewall to the distributor (which I am not seeing on my multimeter), then it should be either a bad ignition switch or a wiring issue (possibly the 2nd fusible link).

Would I be getting power to the gauges and wipers if the 2nd fusible link is bad? I'm almost positive that I am, but I will double check tomorrow.

Does this reasoning fly?

 

[HotRodPC]

Just for ***** and giggles, check your starter to make sure your wires are all connected to where they go and connections tight. Mainly talking about the smaller wires to the solenoid.

 

[suburble]

Just for ***** and giggles, check your starter to make sure your wires are all connected to where they go and connections tight. Mainly talking about the smaller wires to the solenoid.

OK. Worth checking in any case. It's cranking over just fine on the starter, though. Problem is it has no spark and won't fire off.