HI guys,

I went to start my R53 today and it was running like a tractor. I got the EML light and service engine soon. I started messing with the HT leads and found I was getting a spark from 1 and 4 side, but nothing on 2 & 3. A little research and pulled the ignition pack and ran an ohmmeter across 1 & 4 terminals, and 2 & 3. Got 10.7 megohms on each reading. Looking at the 3 pins for the primary coil, I'm getting a little confused. I believe the middle pin should be common and I should get a consistent reading between the middle pin and each of the 2 outer pins. Anyway, I got between 0.5 and 1.2 or so ohms when testing combinations of those 3 pins.

I put a test lamp on the wire connector that goes to those 3 pins and turned on the ignition. On the middle wire I got a light with the ignition switched on. I would have thought this would be ground? On another wire I got a steady light with the engine cranking. I don't think I got a light on the 3rd pin at all....so I'm starting to get confused.

My questions are:
1. Does anyone know what resistance I should see across the primary and secondary coils? I think the secondary coils are okay since they are both the same resistance.
2. Which pins are which on the primary coil, and what should I see with a test lamp when testing the power?
3. What is the next step upstream to look at if it's not the coil pack?
4. Am I working my way to the ECU? How do I know that's bad? Yikes.

Thanks for your expertise,
Mike

 

Throwing any codes?

 

Is it the original OEM coil pack from when the car was delivered ?

 

Good question. No codes relating to missfire. But codes such as airbag and tail lights. I have the OBD scanner from ECS, so I'm not seeing codes, I'm seeing decoded info.

 

Another good question thank you! It is a Screamin Demon coil pack. I've had the car since July.

 

Those packs have known issues and total Junk.....and im being gracious with that description. Did you buy this one new ?

 

^^Very true

 

I've had MSD for 8 yrs now with their wires = Quality product..

And anyone adding hi-po coil packs are essentially throwing money away UNLESS they're also widening the spark plug gap to widen the arc.....More spark = better more efficient fuel burn = more HP/Torque.

Mine are gapped at .050 - Stock is .032 !

I HAD a Screamin Deamon coil pack...and it's exactly that....you'll be screamin your head off swearing at the deamons under the hood with one of those. Even when new it's crap shoot.

**** If you have the stock one still, try that one and see what happens.

 

That's good to hear thank you. I bought the car in July, 101K miles and have made a few repairs so far. I wasnt' banking on engine repairs...but the coil was already there when I got it. I feel like the coil tested good with an ohmmeter, but then again I don't know what the resistance is supposed to be between the terminals. Maybe I should just buy a replacement for it and go from there.

I'd really like to know how to test the unit properly, and also how to test the supply line.

 

Thanks Euro, great info! I don't have the original but will replace the SD and give it a shot. I'm glad to hear it's a dud product by reputation, that gives me hope that it's not a deeper issue.

 

My 2 cents, just go OEM with the coil pack. I bought my car with the MSD coilpack + cables. I decided to sell the MSD coil and keep the cables. I bought a SKV Esen coil pack and it performs well on my R53 Works (211bhp).

 

Wow your engine bay is clean!

Thanks for your input, much appreciated! I ordered an aftermarket one last night, it's a Delphi brand and from my research it's made in Germany. I'm trying to avoid buying Chinese because I don't want Wuhan. I'm not sure if the one I pulled out is a dud yet; resistance test appeared okay, but I can't be absolutely sure it is, so I went with a $40 one, at least as a test. I feel like I may have a deeper problem because I couldn't get the signal voltage (flashing test lamp) from any of the power supply wires. That said, I was getting a spark on cylinders 1 & 4.

I'm an electrician by trade, but often times auto electrics stumps me. I'll post back here when I've tested the new coil on the car later in the week...Thursday is delivery day.

 

Thanks! Its not my daily car and it sits dry in my garage, so that helps alot :D

Agreed, buy from a reputable brand and you should be fine.

 

Well the coil pack came in today. I installed it an no change. Disconnecting bank 2 & 3 I get a weak spark out of it to ground and a strong spark from bank 1/4. It is obviously misfiring cylinders 2 and 3, but wonder what the $13 status means.

As a test I pulled the number 3 lead and placed it on the number 1 cylinder and the lead tested good. I guess the next thing I need to figure out is where the signal comes from where it enters the ignition coil. Seems odd, 2 cylinders (1 and 4) firing, and 2/3 not.

I'd love some advice.

 

Well here I am back to finish off the thread. I found this thread here: https://www.northamericanmotoring.co...tor-issue.html and thought it would be a good idea to trace the wires back from the connector. First thing I noticed was electrical tape around the plastic pipe housing the wires. Hmmm a prior repair perhaps? I removed all the sheathing and found this clumped mess, so cut the wires and reconnected them (soldered), put it back together and runs perfect...but with codes I can't clear. For which I'll start another thread if I can't find any info on them. Codes C0700, C0304, P0300.

Thanks everyone for your help!
Mike