Hi,
I have been having engine missing issues with my 92 M42 when coming off idle or mashing the pedal down at low RPMs. Car has around 230k miles but i did a headgasket and changed all the timing chain and gears 2 years ago and have had 0 problems with it. Car is throwing no codes and it seems to do it more as it warms up but not all the time. I first checked the coils and wires at night and they were arcing to their iron cores and the wires had a bit of arcing too. I tried some S52 coils i had around and picked up a little throttle response but once it warmed up it started again. Tried another set of wires but it still does it. Not sure the cables i put in are good either. They were used. Swapped cam sensors and it still does it. The coils i tried were used and of unknown conditon so it brings me to this project. Stock M42 S50 S52 coils cost $65 each and up and wires are $300ish. Even if i go to a regular COP kit i am stuck with these expensive coils. All the newer engines have the pencil coils and at $30each you can't go wrong. A set of 6 Bavautos hipo coils is $250ish and is still cheaper. So yesterday i decided to do a little proof of concept experimenting.
I have always loved the idea of COP but hated the idea of loosing my clean looking engine bay. I want my BMW cover.
Here are the S52 coils rigged up to test.
Here is a comparison of the later style coil next to the M42 wire end to show the height difference.
Coil no fit, project dead......NOT!!
Looks like the hole in my head is bigger that the cover......
Took the valve cover off and coil has plenty of room.
Grabbed a bad valve cover i had that has broken vent cover bolts to grind on.
Coil boot will not fit but it shouldn't need to go this deep anyways, just checking.
Got the dremel out with a cutting wheel and cut most of the lip off. Left a little just incase.
Chop, chop
Using my porting bit i proceded to open it up.
Ground it just enough for the coil, right side one done.
Coil fits but boot doesn't
This is how high the cover will sit.....sort of.
Decided to butcher a wire boot to make a way to seal the coil.
I guess i could make it work but i am not happy with it. The coil just rattles around.
I opened up the hole more
Went a little too much at the 1 o'clock area but that is the purpose of doing it on this bad cover. Learn learn learn.
Boot fits but it is too tight to get the coil in even with some organic lub.
I opened up the hole more but this time just at the top so i keep the gasket ledge intact. A little messy but it's just a test.
Boot fits and with a little organic lub and the coil slid in like a glove.
Put the car back together and decided to try get a bmw cover to fit the valve cover. I made this template for the brackets. I am going to make it smaller and cleaner.
and lower...... it probably sits too high but again, just want to see if it will work. I'll lower it when i make the brackets out of .090 aluminum sheet.
Sits high here. I hope to lower it a bit once i know exactly how high it needs to be to clear the coils. Should look OK once the brackets are painted black. I will grind up my painted valve cover once all the parts arrive to finish this.
So i have ordered 3 more coils (Bosch 0 221 504 464 OR BMW 12 13 1 712 219 ) and i also ordered an E46 03-05 coil harness for a M54 with the triangular plugs to run to the location of the original coil packs. I plan on cutting the sockets off of my old coils and hard wiring them to the M54 harness to go to the factory M42 coil plugs. I don't want to cut anything on my cars harness.
Hope this helps someone out who has been wondering about the feasability of this project too.
I have been having engine missing issues with my 92 M42 when coming off idle or mashing the pedal down at low RPMs. Car has around 230k miles but i did a headgasket and changed all the timing chain and gears 2 years ago and have had 0 problems with it. Car is throwing no codes and it seems to do it more as it warms up but not all the time. I first checked the coils and wires at night and they were arcing to their iron cores and the wires had a bit of arcing too. I tried some S52 coils i had around and picked up a little throttle response but once it warmed up it started again. Tried another set of wires but it still does it. Not sure the cables i put in are good either. They were used. Swapped cam sensors and it still does it. The coils i tried were used and of unknown conditon so it brings me to this project. Stock M42 S50 S52 coils cost $65 each and up and wires are $300ish. Even if i go to a regular COP kit i am stuck with these expensive coils. All the newer engines have the pencil coils and at $30each you can't go wrong. A set of 6 Bavautos hipo coils is $250ish and is still cheaper. So yesterday i decided to do a little proof of concept experimenting.
I have always loved the idea of COP but hated the idea of loosing my clean looking engine bay. I want my BMW cover.
Here are the S52 coils rigged up to test.
Here is a comparison of the later style coil next to the M42 wire end to show the height difference.
Coil no fit, project dead......NOT!!
Looks like the hole in my head is bigger that the cover......
Took the valve cover off and coil has plenty of room.
Grabbed a bad valve cover i had that has broken vent cover bolts to grind on.
Coil boot will not fit but it shouldn't need to go this deep anyways, just checking.
Got the dremel out with a cutting wheel and cut most of the lip off. Left a little just incase.
Chop, chop
Using my porting bit i proceded to open it up.
Ground it just enough for the coil, right side one done.
Coil fits but boot doesn't
This is how high the cover will sit.....sort of.
Decided to butcher a wire boot to make a way to seal the coil.
I guess i could make it work but i am not happy with it. The coil just rattles around.
I opened up the hole more
Went a little too much at the 1 o'clock area but that is the purpose of doing it on this bad cover. Learn learn learn.
Boot fits but it is too tight to get the coil in even with some organic lub.
I opened up the hole more but this time just at the top so i keep the gasket ledge intact. A little messy but it's just a test.
Boot fits and with a little organic lub and the coil slid in like a glove.
Put the car back together and decided to try get a bmw cover to fit the valve cover. I made this template for the brackets. I am going to make it smaller and cleaner.
and lower...... it probably sits too high but again, just want to see if it will work. I'll lower it when i make the brackets out of .090 aluminum sheet.
Sits high here. I hope to lower it a bit once i know exactly how high it needs to be to clear the coils. Should look OK once the brackets are painted black. I will grind up my painted valve cover once all the parts arrive to finish this.
So i have ordered 3 more coils (Bosch 0 221 504 464 OR BMW 12 13 1 712 219 ) and i also ordered an E46 03-05 coil harness for a M54 with the triangular plugs to run to the location of the original coil packs. I plan on cutting the sockets off of my old coils and hard wiring them to the M54 harness to go to the factory M42 coil plugs. I don't want to cut anything on my cars harness.
Hope this helps someone out who has been wondering about the feasability of this project too.
Comment