ignition problems

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pjc360

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I'm having trouble with what i think is the ignition, everytime i start it up when its cold outside it pops and bangs thru the exhaust and it sounds really muddy but it will smooth out once i get the rpms up a little bit, then when it warms up to operating tempature it almost completely goes away but my engine is idling pretty high and i have the idle on my carburetor turned all the way down, what could be causing this?
It's a 360 crate engine magnum in a 1991 dodge power ram, its carburetated fuel injection and computer are gone, the owner before me had the charging system wired up wrong, he had the blue wire coming from the voltage regultor tied into the primary side of the ballast resistor, i was told that blue wire needed to be tied into a 12v ignition source, so i tied it straight into my ecu power wire. Ever since i tied the blue wire from the voltage regulator i fried the original ignition module, i dont know if having the blue wire from VR tied into the ecu power wire caused the module to fail, or if it was already on its way out and failed do to the overcharging that was going on from the previous owner having it wired up wrong.
I am at a loss here.... i do not know what is causing it to run muddy and pop and pop and sputter out the exhaust, the two things that come to my mind first is the timing and then the coil, is it possible i fried the coil with the overcharging? is there a way i can test the coil to find out if it is still good on my own? how many volts should be at the coil while running and all that good stuff? when i timed it i timed it while the charging system was wired wrong because i was not aware of the overcharging problem, is it possible that what sounded good while the overcharging was going on is not working now that the charging system is working right?
I just dont know, timing and coil are the only two things i can think of that are causing this, distributer cap and rotor are brand new as well as the coil and the ignition module, any advice or opinions would be greatly appriciated.
 
Hard to read with few sentences, paragraphs, or capitals, which is probably why most didn't even try.

You say it is a Magnum crate engine in a 1991 RAM, so I assume you have the "barrel keg" intake w/ multi-port injectors. You confuse me when you mention a "carburetated (sp) fuel injection and computer" (what is that?) which is now "gone", yet you still have an ECU.

If you do have the "barrel keg", a common problem is that the sheet metal cover on the under-side pops a leak. This causes it to suck air, plus oil, so it runs lean and the spark plugs foul. It sounds to me more like a lean problem than ignition. A guy on ebay sells a thicker aluminum plate (~$100) that holds much better than the factory cover and solves the problem. He even has an improved design (~$150) with a deflector V for better air flow, if you also cut back the air runners. It would also be very stiff. For either, you must remove the intake, which is a bit of a hassle in a SB since you have to drain the coolant, etc. BB intakes are easy to swap.
 
First, it may not be ignition, but rather carb/ vacuum leak

But the blue to the alternator field, one of the regulator (IGN) terminals, and the "input" side of the ballast resistor is SUPPOSED to be tied together. Refer to these simplified diagrams:

A simplified diagram of the older "5 terminal" ECU NOTE the notch in the ballast, it's important it be oriented this way:

Also, you can wire the vehicle for a 4 pin ballast and use EITHER a 4 or 5 terminal ECU. You can NOT tell by looking if an ECU is 4 or 5 pin, as some 4 pin ECU's have 4, some 5. The only way to tell for sure is to use an ohmeter on the "5th" pin to see if it's hooked up or not. If you wire for a 4 pin ballast, it does not matter which ECU

The diagrams below are meant for "conversion." Note the wire at top right marked "existing wire" which represents the dark blue (in many cars) which comes from the key through the bulkhead and is the "switched igntion" or "run" sometimes called "IGN1" by mopar

THIS POINT in the harness, labled "existing wire" is where the factory "Ys" off to the IGN (blue) terminal at the regulator and the blue field connector at the alternator, AND electric choke, if used, and I BELIEVE distributor retard and idle solenoid, if used.

WHAT IS NOT SHOWN is the (sometimes brown) "bypass" wire, which comes from a separate contact in the IGN switch, through the bulkhead, to the + side of the coil. This switch contact only does one thing---when the key is in "start" the brown is hot, and feeds hot 12V to the coil + for starting.

Ignition_System_5pin.jpg


Wiring for a 4 pin ECU, note the 2 pin ballast

Ignition_System_4pin.jpg


Something that is getting to be a huge problem, I write in just about every post, is VOLTAGE DROP in these old harnesses, caused by corrosion in connector or in the ignition switch. Problems are typically in various connectors, ESPECIALLY in the bulkhead connector

READ this excellent article at MAD electrical:

NOTE I don't know what changes they made in your later truck, so some of this might not apply

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

which came from here:

http://www.madelectrical.com/electrical-tech.shtml

One thing you need to get, and I don't have access to, is at the very least a wiring diagram for your vehicle and better yet a shop manual. If nothing else, you should be able to get one on CD from the eBay.

I would make some voltage checks to confirm or eliminate voltage problems in your rig.

Check voltage at the IGN supply wire coming out of the bulkhead to the "key" side of the ballast. Best way to do this is to measure voltage drop directly. To do so, set your meter on low DC volts, turn the key to "run" with the engine OFF.

Stick one probe onto the battery pos. post, and the other onto the "key" side of the ballast. You are looking for a low, very low voltage, the lower the better. If you show over .2v (two TENTHS of a volt) be concerned, try to find out why, if it's approaching or over 1/2 volt, or more, REALLY did in and find out why
 
ok, i have a 4 pin ignition module, its brand new nd i got it from car quest, this truck is carburated, no fule injection at all, it was tbi originally but the person i bought the truck from tore all that out and put a crate 360 magnum in it with a 4 barrell carb, the ignition module is a 4 pin but my plug that plugs to the module is a 5 pin. I checked voltage to my battery positive post it reads 13.8 volts, i checked the volts at the positive side of my coil with the key on and i get 12.3 volts, i checked the volts on the negative side of the coil and it was very low 1. something. In my haynes repair manual it says if the negative side of the coil is not within 1 volt of the positive side of the battery then it says ignition coil is faulty and should be replaced.
In my repair manual it shows how to test the ignition coil with an ohm meter it says that the primary resistance of the coil should be at 01.3 and that the secondary resistance of the coil should be at 13.51, so i pulled my coil off and tested it and the primary resistnce on my coil is 02.0 and the secondary resistance of my coil is at 9.81, it says in the repair manual if the coils measured resistance's are not as specified the coil is defective and should be replaced.
Thank you for the pictures 67dart, i have alot of them drawings in my repair books, but you can never have enough of them, so what you are saying is me tying the blue wire from voltage regulator staright into the ecu power wire can cause problems? the directions that came with the voltage regultor said green wire runs straiht to altenator field terminal nd the blue wire runs from a 12v ignition source to the voltage regulator and then on to the other altenator field terminal. So i dont understand why it would matter where the voltage regultor was getting the 12v ignition source from, as long as it is getting a 12v ignition source, correct? The previous owner had that blue wire from the voltage regultor wired to the primary side of the ballast resistor, there fore the voltage regultor was not reading right and sending way too many volts to the battery and whatever else, so i'm thinking with that overcharging problem cause of it being wired wrong fried the coil and the voltage regulator and it darn near fried my bttery too. the crburator is brand new, it dont even have 1000 miles on it and i adjusted the idle air mixture screws with a vaccume gauge.
I just dont understand why my engine is idling so high, the idle on the carb is turned all the way down and the engine is still idling high, do i need to re-time the engine? is it possible that since i timed it while the charging system was not working right that what sounded good then is not good now? i just cant figure out this high idle its strange.
 
pjc360 said:
, i checked the volts at the positive side of my coil with the key on and i get 12.3 volts, i checked the volts on the negative side of the coil and it was very low 1. something. In my haynes repair manual it says if the negative side of the coil is not within 1 volt of the positive side of the battery then it says ignition coil is faulty and should be replaced.
.
Click to expand...

Voltage at the positive side of the coil SHOULD be "downstream" of the switched voltage and should be in the range of 5-8 depending on the resistor. Sounds like you have it wired wrong, and have switched 12V going to the coil + Do this test again, check BOTH sides of the resistor. Haynes is wrong, the neg side of the coil SHOULD be low, 1 or 2 volts.

pjc360 said:
In my repair manual it shows how to test the ignition coil with an ohm meter it says that the primary resistance of the coil should be at 01.3 and that the secondary resistance of the coil should be at 13.51,
Click to expand...

The coil primary should be in the 1.xx to 2 ohms range, depending on the coil. The secondary should be more like 13K ohms, meaning 13,000, or 13,510. Read your book again, and see if it does not have a K after that figure. Measure again, be careful not to get your fingers on the probe tips, and use a higher range on your meter


pjc360 said:
me tying the blue wire from voltage regulator staright into the ecu power wire can cause problems? the directions that came with the voltage regultor said green wire runs straiht to altenator field terminal nd the blue wire runs from a 12v ignition source to the voltage regulator and then on to the other altenator field terminal. .................. The previous owner had that blue wire from the voltage regultor wired to the primary side of the ballast resistor, there fore the voltage regultor was not reading right and sending way too many volts to the battery
Click to expand...

When you get some of this sorted out, I can point you to more tests regarding the regulator. NORMALLY, one terminal of the ballast, the "key side" is indeed used to "Y" off to the regulator and field. It does not matter where you "Y" the blue AS LONG as the Y is on the proper side of the coil ballast. One example is---Blue switched ignition ("ign run") comes through bulkhead connector --goes to Y-- from the Y you have:

1 to the "key" side NOT the coil side of the ballast the other terminal of the ballast goes to coil +

2 to the wire indicated in the drawing above, to the correct pin of the ECU

3 to the blue going to one of the field terminals of alternator

4 to the blue IGN terminal of the regulator

5 to the electric choke if used

Sounds to me like you have the blue going straight to the coil, instead of through the ballast.

The green indeed goes directly from the regulator to one field terminal. These do not matter, you can switch the blue/ green at the alternator


pjc360 said:
I just dont understand why my engine is idling so high, the idle on the carb is turned all the way down and the engine is still idling high, do i need to re-time the engine? is it possible that since i timed it while the charging system was not working right that what sounded good then is not good now? i just cant figure out this high idle its strange.
Click to expand...

The charging issue should not really affect a timing problem. You need to get a light on it and see where it is. High idle is probably a vacuum leak somewhere.
 
The only way an engine can idle at high rpm is if it is getting too much air. If your throttle plate is almost closed, i.e. the idle speed screw is in the normal position and the choke is open (speed cam out of the way), then it must be getting air from somewhere else, i.e. a vacuum leak.

Check the common and easy places first. Detach each vacuum hose from the carb and plug the port, one at a time - PCV, brake booster, vacuum advance, charcoal canisters, etc. If it slows way down for any one, you found the leak. Since you say the idle is really high, I would suspect the big hoses (PCV or brake). You could also have a leak at the throttle shaft of the carb. For many hoses, you can hear it hissing. I fixed a relative's Honda Civic once. They said the engine "sounded funny" at idle and was rough. It was idling ~1500 rpm and I could hear the hiss from a 1/4" vacuum hose. Popped it back on and it purred like a kitten.

Some people try flowing propane (not burning) around the intake - head junction and the carburetor base to see if the engine idles smoother (but not slower), in searching for a vacuum leak. I have heard of spraying carburetor cleaner similarly (but not around rubber diaphragms!).
 
what kind of carb is it?
if the lines are not in the right spots you can have these kinds of problems...

for newer holleys i'm pretty sure it's the distributor vaccum advance - right side of carb
pcv + accessory misc vacuum front of carb
power brake rear of carb
 
sorry i have not been talking, been gone for a couple days, and to clear some things up, when i turn the key on i have 13.6 volts at my battery and 12.5 volts at the positive side of the coil and i have 1.5 volt at the negative side of the coil, wonder why haynes says the negative should be 1 volt from the battery voltage? Anyways so if 13.5 at battery is normal and 12.5 volts at the positive side of the coil is normal and 1.5 volts at the negative side of coil is normal then it should be wired right, could it be my ballast resistor causing it to run a little muddy when i first start it up? or does that sound like a vaccume leak as well? my carb is an edelbrock 600cfm manual choke, i did put a new air filter on it, i had a different air filter and i threw on an edelbrock air filter case with a bigger filter... maybe i knocked a hose loose somehwere i'm pinching a hose off somewhere? i dont really know, i'll check it all out tommarrow, this thing with the voltage regulator is still conbfusing me tho... I talked to a guy on ramchargercentral.com and he told me to wire the blue wire from voltage regultor to the ecu power wire and that it'd be fine???
 
The battery cannot be 13.6 unless it's running. You must have meant 12.6?

12.6 at the coil is way too high, should be more like 6-8 so you must have the switched ignition power going to the coil, IE wrong side of the ballast. Refer to the diagram I posted.

I don't know how I can make this more clear:

The dark blue switched ignition wire coming OUT of the bulkhead FROM the key should be hooked to one side of the ballast.

ALSO hooked to that end of the ballast are the blue field wire, the blue IGN lead to the regulator and IF you have a 2 pin ballast, the wire going to ECU power should be hooked to that same end of the ballast. In the diagram above, with the 2 pin ballast, that wire is labled "new wire" because this is a conversion diagram

ONLY the coil + wire AND the brown bypass which also comes from the bulkhead and the key should be hooked to the OTHER side of the ballast

The wire going off the diagram at the very top right labled "existing wire" represents the dark blue switched ignition coming from the bulkhead

WHAT IS NOT SHOWN in that diagram is the brown bypass coming out of the bulkhead. It goes to the + side of the coil OR the coil + side of the ballast

The guy on Ramchargers is INCORRECT
 
I have nothing more that I can ad to what is said above to help you, first like said above the coil has too much power going to it with the key on.
This is what the ballast resistor does reduce voltage to 5-8 volts except with the key in the start postion (battery voltage)

any dark blue is power with the key on for the most part, chrysler usually taps into the harness for the electronic ignition around the distributor area from factory (the voltage regulator dark blue)
 
The part about "run muddy and pop and pop and sputter out the exhaust" sounds like crossed plug wires...
 
ok, just so i understand this.... and so there is no confusion here between us, when i turn the key to the run posistion i get 13.6 volts from the battery, with the key turned on i'm getting 12.6 volts at the positive side of the coil, with the key on the on position i'm getting 1.5 volts to the negative side of the coil. If that is too much going to the coil then i will have to order another brand new ecu wire harness connector and tear all of that out and start over, my question is since i have a 4 pin ignition box can i use the two prong resistor starting over? and if so does this make it easier to wire up? i am a complete tard when it comes to wiring.... sorry but im a visual learner touching feeling and watching i'm not the type of person that can read something and then automatically know what to do, specially when it comes to wiring, that might explain why my coil gets pretty warm while running, i'm suprised it starts and runs with the many volts going to the coil and with it being wired wrong..... I could slap the previous owner of this truck he messed so many things up was a complete retard. i have had to correct so many things because of him.
 
You need to be more specific, or all we're gonna do is keep going round in circles.

Are you trying to tell me you are measuring 13.x volts WITH THE ENGINE NOT RUNNING?

If so, you have something wrong with your meter.

You don't need to trash the harness, you can rewire what you have now.

YES if you are sure you have (and are going to use) a 4 pin box, all you need is a 2 pin resistor.

12.6 at the coil is too much, for about the third time.

One thing that might help is to draw it out yourself.

Draw a picture of the coil, ballast, regulator and ECU.

Start at the ECU follow EVERY wire to where it goes.

Find the blue at the regulator and follow where it goes

Find the blue at the alternator and follow where it goes

Everything should "funnel" to the ballast and the bulkhead

You really at this point might want to find some local help. Surely you have a friend/ Dad/ Uncle/ etc that's good with wiring.

All you need to do is print out one of the diagrams I posted, and follow it.
 
if my old man was still alive i wouldnt have to ask any questions on this site at all, and i hope nothing is wrong with the meter its a very nice craftsman meter and i put brand new batterys in it before using it, the multimeter, and yes i read 13.5 volts on the positive side of the battery with the key on and the meter grounded to the negative side of battery. an i am meausuring in VDC.
I am sure i could get by with the 5 pin harness i have, but its hacked to **** and very old all the connections at the ballast are rusty and crappy looking. it would make it easier for me to get a brand new electronic ignition wiring harness and to tear all the old crap out and start fresh with new wires, and i printed of your diagrams, thanks by the way.
And i already know where the blue wire from my altenator goes, it goes straight back to the voltage regulator and from there it goes across the fire wall and ties straight into the ECU power wire. I think getting rid of this 4 prong ballast would help simplify this for me as well.
 
I dont understand why having the 5 pin modules required 2 extra prongs on the ballast resistor? but whatever, i thought about ditching it all and wiring in a gm hei ignition but i decided against it, i know the mopar ecu ignition works well, i just need to get it wired up right. the idiot that had the truck before F'd alot of stuff up on it.
 
I know a mechanic of 20 plus years that i am sure would stop by and give me a hand wiring in a new controll unit wiring harness, he is not a huge mopar guy, he deals more with the fords, but i am sure with the two of us we can figure the thing out.
 
Ok, so i ordered a new electronic ignition wiring harness, it should be here next wednesday or thursday. I have looked at all of the diagrams and looked alot online trying to get to the bottom of this, the green wire from the voltage regulator runs from the voltage regulator to the back of the altenator to one of the field terminals, the blue wire runs from the other field terminal on altenator to the voltage regulator then it ties into the ecu power wire. I dont understand why this is wrong? it may not be the way dodge wired it originally, but why wouldnt it work? it says one wire oes to voltage regulator to altenator and the blue wire comes from other altenator field terminal to the voltage regulator and then off to an ignition power source, or just plain old ignition. Why would it matter where the voltage regulator gets the 12v ignition from? as long as its getting a 12v ignition source you'd think it wouldnt matter where as long as it is getting a 12v ignition source?
 
you will probably be wiring it like the bottom picture. print that out for your mechanic buddy so he has it when he stops by. note: the coil has 1 wire going to the ecu (marked with a - ) and 1 wire going to the ballast (marked with a +). that is it. the ballast gets hooked to your IGN (the line that goes hot when you have the key to the on position)
 
Yes i would like to wire it up like the bottom photo, i wanna get rid of the 4 prong ballast resistor, i dont need the 4 prong resistor anymore, i have the 4 pin ignition module so i shouldnt need a 4 prong resistor correct?
I have printed off everything you guys have posted as far as instructions and pictures.
And i appriciate everything you guys have posted to help me, for the most part i understand what i have to do, the only thing that is confusing me is the excisting wires in the pictures and how to wire the voltage regulator, i know how to wire half the voltage regulator, the green wire runs from voltage regulator straight to altenator and the blue wire runs from altenator to the voltage regulator and then off to a 12v ignition source, i was told i could just tie the blue wire running from the voltage regulator to the ecu power wire and it would be fine, is this correct? or am i going to hurt something having it wired this way? i figured as long s it is wired to a 12v ignition source that it would be fine?
 
I totally forgot to mention this, and this is more less a question for 67dart273, my ignition is currently wired to a toggle switch, the previous owner told me that the ignition switch was most likely burnt out, and instead of replacing it, he spliced a wire into one of the red wires in the loom that goes to the 5 pin ignition module harness and wired a toggle switch up. Now my truck will not start unless that toggle switch is flipped on, and it will not shut off ether unless the toggle switch is shut off.
So my question is, should i have the blue wire coming from my voltage reulator spliced into the same wire that the toggle switch is wired to? this would be a 12v ignition source so i dont see why it wouldnt work, and i was also told i could have it wired to the ecu power wire as well and it would be ok. the way it was explained to me and as i understand it the voltge regulator needs a 12v ignition source and it really doesnt matter where it gets the 12v ignition source, as long as its switched ignition source. I'm a little baffled with the way this guy has this truck wired, the wire that the toggle switch is getting power from is not the ecu power wire, but another red wire that runs to that 5 pin module connector.
 
I bought a 64 and 65 Mopar in the last few years and both had the wiring harnesses hacked up. It seems few people know how to wire correctly, including many "professional" mechanics. One fool installed an electric fan (no mechanical fan) and ran ~20 awg wire ~8 ft to power it off the ign wire (twisted together and taped). The factory wires out of the fan are ~12 awg, which should have been a tip.

To answer your question. Lose the toggle and replace your ignition switch. I got one recently for ~$8 at rockauto. You do need to swap your key cylinder, but that is easy (push in release w/ paper clip w/ key in correct position).

To answer your 2nd question, it kind of does matter where the voltage regulator gets its 12 V. Think of that as the "sense wire". It adjusts the alternator to regulate the sensed location to its preset (~14 V). You do want that to be a switched ignition source, otherwise Vreg will run down your battery when sitting. I would pick the most upstream position, which is where the ign wire first lands after coming out of the bulkhead before branching to other devices. In my 65, that spot was the terminal where ign feeds the ballast resistor. I re-wired mine with an under-hood ign relay, so wired Vreg to the relay output.
 
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