Running Rough All of The Sudden!!

[stingus]

Driving home friday my Bronco started running like crap. Feels like its missing spark throughout all rpm ranges and gears. Was idling smooth before and now idles so rough and eventually stalls out.

Here's some info: I just put a new Pertronix Flamethrower Distributor with Igniter 2 ignition on it 4 weeks ago, new Voltage Regulator 4 weeks ago, new coil last night, new plugs and wires last night.

No visible cracks in the Dist cap, changed fuel filters a month ago. All Plug wires are attached properly.

I'm going to run a compression test on each cylinder this week and try and find someone to check the timing. Can it just jump timing while driving?

Any suggestions on what else to look for is appreciated!

thanks!

Any suggestions on what else to check?

 

[daddycreswell]

I'm a newbie, but last week mine went from running fine to running rough, come to find out the plug wires had fallen down onto the headers and burnt the plug wires, also the points were bad. Might want to check those. Good luck.

 

[Bullitt94]

When people ask me about a miss in the engine the first thing I always do is tell them to run a carb/fuel injectoer cleaner in the gas tank (I prefer Sea Foam).

If it doesn't start to clear up after a bit then I would park in a dark garage and start it or fire it up at night. Pop the hood and look for spark jump. If you see a spark, then that's where your problem is.

If you don't see sparks, if you can get the engine to idle try pulling one plug wire off at a time. Each one you pull off should effect the idle. If one doesn't, then you have a problem w/ that cylinder, valves, plug, etc.

If all the plugs effect the idle, then take a carb cleaner and spray around the intake seals while it's idling. If the engine revs, then you have an air leak issue.

I hope this gives you a good place to start.

 

[DirtDonk]

...new coil last night, new plugs and wires last night.

Were they replaced BEFORE this issue? Or BECAUSE of it?

Paul

 

[broncnaz]

I'd check the gap on the ignitor setup. I know people have had issues when the gap is not correct. also check all wiring connections to the igintion.

 

[stingus]

I'd check the gap on the ignitor setup. I know people have had issues when the gap is not correct. also check all wiring connections to the igintion.

I wired a 2 port power outlet to the back of my ignition switch a while back. I don't think I had any ignition issues before that. Any chance since it is wired to the stud on the back of the ignition switch that it could be causing a surge or problem?

Thanks!

 

[stingus]

Were they replaced BEFORE this issue? Or BECAUSE of it?

Paul

All because of some ignition gremlin. It was starting but not running when gas was pressed and we narrowed the problem down to the distributor. After the new distributor it was running fine for about 4 weeks until this past friday. Thats when i replaced coil. plugs, wires with no change.

Also, I noticed that under the Distributor cap there were black burn marks at the brass connector points. it looked like some plastic around them had melted too. I'm gonna replace the cap and rotor this week but what would make a new cap and rotor go bad?

I have a power port wired to the back of my ignition switch that sits on my ignition wire as well. Any chance this is causing surges or something through my ignition wire to the coil and distributor?

 

[stingus]

I'd check the gap on the ignitor setup. I know people have had issues when the gap is not correct. also check all wiring connections to the igintion.

How do I check the gap on the ignitor setup?

 

[broncnaz]

should have come with instruction on how to set the gap. I know the standard ignitor setups does. its kinda like setting the gap on points. The way you have it wired should be fine as long as the connections are good.

 

[Explorer]

"If" you have something powering off the ignition wire, yes, it can cause problems. Nothing else should be powered on that circuit. Thats why you bypass the resistor wire on a Petronix to start with. It needs full battery voltage.

 

[stingus]

"If" you have something powering off the ignition wire, yes, it can cause problems. Nothing else should be powered on that circuit. Thats why you bypass the resistor wire on a Petronix to start with. It needs full battery voltage.

I do have the power port wired to the back ogf the igition switch and through a relay switch that runs to the battery. I will take it off tonight. My pertronix is hooked up to the pos and neg wires on the coil. Is that incorrect?

 

[broncnaz]

What coil do you have? Are you using the stock wire to power the coil? If so you need to run a seperate line for the red ignitor wire thats a full 12V.

 

[stingus]

What coil do you have? Are you using the stock wire to power the coil? If so you need to run a seperate line for the red ignitor wire thats a full 12V.

I have a new stock coil. I am running the stock wire to power the coil I assume. The red ignitor wire is running to the positive side of the coil as well, the neg wire from the coil is running to the neg side of the coil. I have 3 wires connected to the Pos side of the coil including the ignitor.

When you say run a seperate line for the ignitor, where do I run it to?

 

[broncnaz]

Ignition switch igintion terminal or any other switched power source. The ignitor must have a full 12 volts. the stock coil feed has a resistor which will draw the voltage down to 8-9 volts or so.

 

[vbro]

I had a problem with unburnt gas. My rig was running way too rich and running rough. It ended up being a vaccum valve off of the fuel bowl. Fuel was leaking into the vaccum line, into the intake. I had 4 cylinders getting too much gas. After rebuilding the carb and a week of driving, I was running smooth.