serious spark/car problems LONG - HELP *LOOK*

Bacondoggy

Registered User
ok my dad has this ignition firing indicator - wich looks like a pen with a red plastic tip grooved out to fit a spark plug wire. let me first say I bought a brand new set of spark plug wires about 8 months ago, and have driven the car about 3k since the new engine has been in. now this indicator has 2 led's a green one (to indicate its on) and a red one the flashes each time it senses a spark. it also has a sensitivity adjustment so the red led would be on almost all the time or flash flash flash for each spark. well this is really messed up - I was measuring from the coil pack and 456 and REALLY strong signals. NOW 123 ALL had VERY VERY weak signals. by the supercharger snout there was no signal. could these wires be bad already?!?! because RIGHT by the boot on 2 and SOMETIMES 3 (I think) you could get a reading and none on 1. I had the brilliant idea to take the one boot (#1) off WHILE THE CAR WAS RUNNING and sparks started jumping and it scared the crap out of me. I had my bro turn it off immediatly. now WHY just by the supercharger does the signal get lost? I am sure there is SOME energy going to the plugs because when I replaced my old ones, they were all in the same condition. (pretty fouled w/ decent carbon and they were only in for 3k). I know the plugs are not an issue - I replaced them with the stock motorcraft doubble platnum's like not even 100 miles ago. I don't drive the car because it is soo jacked up. now just sitting in idle, the check engine light comes on and flashes... I replaced the O2 sensors like 2k ago, but my dad said they could have melted or got fouled from the messed up fuel/air mix (DEF. a problem). ANY help would be VERY greatful.
 
Run a codescan to find the specific codes for your problem. Also, you can use a multimeter to measure the amount of resistance in your plug wires.
 
pearl95sc said:
Run a codescan to find the specific codes for your problem. Also, you can use a multimeter to measure the amount of resistance in your plug wires.

Most likely because the wire tester you were using employs a diode that lights when current is induced in it from the wire. Since the current flows one direction on one side of the motor and the opposite direction on the other side, the diode won't light. All the light you are seeing is from residual EMF on the wire. It might work if you test the wire from the opposite side (reverse the direction of the tester) but I'm not sure on that.

If you want help with the problem you are going to have to be more specific with the symptoms.
 
so you are saying that a checker that is designed to check spark plug wires doesn't measure 1/2 of the wires??? the diodes are designed to let current/volts one way and stop them from going the other way (much like a PCV valve), but there are led's (and led's are like diodes also). so is the tester totally garbage? I know that the tester picked up the 123 charges. if it was only geared for positive polarity then it wouldn't... I am confused I don't know why less voltage goes to half the engine. is there a way to test the coil pack???
 
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LED = diode. LED "Light Emitting Diode" So yes, it will be affected by the direction of the current flow.
 
well the tester is a solid state. you can turn it around it doesn't matter. It is true that diodes only let current go one way, but it is checking for current. + or - .
 
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haha - I'm just going to take some advice and swap the plug wires... the ones on the drivers side *should* reach over to the pass side, right??
 
Why didn't I think of that?

I don't know what the benefit of having each pair of plugs in series is, as compared to having them in parallel. Anyone knows?
 
I did think of something else, though. You need to swap the wires at the coil pack only. If the wires don't reach, then try rotating the coil pack 180 degrees.
 
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