melted coil

[kurthansen]

Hi, everybody-first post.
I drove my '95 ti to Killington, VT last weekend, and it's still there-Help! Sunday morning was -23F. went out to start the car but it would only sputter. Seemed like a frozen fuel line. Shot some starting fluid in the intake and induced it to run, but on only three cylinders. Soon thereafter, the area of the coil at the #3 plugwire smoked and melted. Opened the coil and saw a big crack in it. I assumed the coil had cracked because of the cold. Hitched a ride back to MA (3 hours drive). Went back today with a replacement coil, hooked it up, and the car fired up on three cylinders and fried the new coil in exactly the same place.
Well, to make a long story even longer, I went to Mountain Auto Sport and spoke with Kermit Upton, A famous BMW Guru. He had never seen this before.
I have spoken with my mechanic, The dealer tech advisor, The parts guys at Greenfield Imp. Car Pts, (very savvy guys) and no one has seen this happen, but I have had several guesses as to what it could be...
1. The #3 plugwire is bad, causing a voltage buildup at the coil
2. The electrical control unit needs to be "checked".
Do I get a third coil, new wires and plugs, go back up to VT and plug the parts in and hope I can drive it home?
Do I risk frying a third coil if the control unit is bad? The Bently manual says to check the control unit before replacing a bad coil, but this means flatbedding the car 200 miles to the dealer for a diagnostic. The cost of a new control unit is over $1200.
Anyone have any advice or seen this phenomenon before?
I ran my '83 320i up there today to try to rescue the 318ti. The old bBimmer has soldiered on valiantly for over twenty years and never left me stranded. Does anyone see the irony here?
Thanx in advance,
Kurt

[bimmerboi318]

my guess would be the plug wires are shot. i dont think that anything on the control side of the coil could fry it but i may be mistaken. by the way how much does the coil pack cost? i do know that the plug wires are very expensive. i'd say replace them all at once though to avoid this happening on the other cylinders.

[318tibimmer]

well, I would see if you can get whoever to just replace that Coil that you bought and the go back with the new coil, plugs, and plug wires - Could be any of them. If there was any type of short then that would cause the problem. Getting your car towed 200 miles will be very expencive. Just a thought.

[kurthansen]

Many thanks for the prompt replies!
O.K., I will go back up to God's country with a new coil, a set of plugwires, and at least one fresh plug for #3.
I bought the coil used from Mountain Auto Sport for $90. It came out of a '95 318ti that Mr. Upton put a 6 cylinder M3 motor in.(YEEHA!) I doubt anyone would refund the cost of an electrical part.
The cost of a new coil at Greenfield Imported Car Parts is $125, the dealer wants $188. M.A.S. has a set of used plugwires, but now is probably not the time to get cheap.
In honesty, the 318ti has been very reliable and a joy to drive 'till now. Just turned 100K miles. I suppose this could have been forseen.
Thanks again, fellas!
Kurt
P.S. It was -14F with a high wind when I pulled the coil and I was about 5 minutes away from frostbite and all the plastic bits under the hood were very brittle. Maybe this weekend will be a little more moderate.

[J!m]

I dont have a definative answer for you, but a piece of advise that may serve you well:

I would not drive that car on a BET!!

Please tow it to the nearest dealer!

Most dealers charge only 1 hour labor to test (about 80-95 $) and will not do a repair unless you authorize it. But, I would just bite the bullet and get it repaired as soon as possible, as driving for any length of time will not be good for your motor or electrical system AT ALL, and I'm not sure how the rest of the electrical system would acept this idea. Perhaps a nice FIRE to keep warm??

Attempting the 3 hour drive is a bad idea... SOMETHING made that coil go bad, and the second one in short order, so I personally would not drive it at ALL until the root cause is found. It may be just a bad plug wire or plug, but what if it isn't???

Food for thought...

[kurthansen]

Thanks for the reasonable reply, Jim.
What I am thinking about doing is putting in a new coil, wires and new #3 plug. It will fire right up, even on three cylinders now. I'll put on the parts and fire it up. If it's still running on three, I'll shut it right off and follow your advice. Now the question is: Do I call in a favor and ride up with a flatbed in case it doesn't work?

I guess it's a matter of being expensive or REALLY expensive!

Anyone know if there is a BMW dealer in central Vermont?

Twelve hunnert long green for an electronic brain, eh? Jeez! there's a solid '74 2002 I know of for about that .

[J!m]

I might not be a bad idea- the 2002 parts are much cheaper...

[kurthansen]

If another Bimmer follows me home, my wife might have a hemmhorage. Right now I have an E30 325is daily driver, an '83 3201, another immaculate 3201, and five parts E21 cars.
But that 2002 would sure be nice. I wore out a few and NEVER came home on a flatbed!

[kurthansen]

Went back to Killington to try and rescue the 318ti. Installed new plugwires, coil, and plugs . Problem NOT solved.
Car will be flat bedded to the nearest dealer-125 miles- and diagnosed.
While I was out getting starting fluid last weekend, some good samaritan tried to jump my car with his pickup truck. He had put the ground cable on the negative terminal of the battery- not on the engine block. He said,

" I got her runnin for ye fer a couple minutes, but then she died."

Thanks a lump, Gomer. Could this hamfisted move have fried my electronic control module?

[318tibimmer]

ohhh, that sucks - keep us posted as to the probelm that is found

[bimmerboi318]

i dont think that putting the jumpers on the batteries directly will hurt anything (that i know of). i was told that putting the negative cable on the block of the car to be boosted is to prevent the sparks from igniting the gasses that may be coming from the potentially overworked battery. i have boosted many a cars including mine by just connecting the batteries direct. but i do not claim to be a professional. (although im on my way im going to school for auto tech )

[2ndBimmer]

Ive always tried to connect the negative to the body of the car to be jumped but it hasnt always happened, or I was with an 'expert' ( ) and they insisted on +/+, -/- connections. Never had a problem when connected that way though. [i do have a story about push-starting my car with a dodge ram though. ]

[bimmerboi318]

push starting with a ram eh? ive got a couple scars from a 4 wheeler doing that haha. one time my battery was so dead (i kinda left my car parking in temporary parking with the flashers on and forgot about it for 2 days) it wouldnt start by push starting it. apparantly the ecu has to have a little juice for the car to run.

[2ndBimmer]

Yeah, the bumper of a Dodge Ram lines up with this cars high tail pretty darn well.

[J!m]

Not positive of the requirements of the ti's ECU, but most need a minimum of 9 volts to even think about running. (A common trick is to rig a 9V battery to a lighter plug when disconnecting the battery- saves the clock and radio reprogram on most cars, yet will not spark like a charged 12V car battery if shorted.)

It's like trying to pop-start a 2002 with the low tension lead off the coil...