New Turbo Build Doesnt Start. Popping Coils

Discussion pertaining to positive pressure E28s.
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e38740imd
Posts: 430
Joined: Jun 17, 2013 12:36 AM
Location: Maryland

New Turbo Build Doesnt Start. Popping Coils

Post by e38740imd »

Good Evening Guys.

i recently finished up this turbo build on my e34 535i (m30b35)

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running MS2PNP so essentially its plug up and go. i set the settings to use wide band and attempted to set injector size (running 80lbs injectors)

as i try to start the engine cranks but doesnt fire. its getting fuel. can be easily smelt through the temporary up turn exhaust.

so it means that im getting no spark? all my ignition coils keep popping or blowing up and i dont know why. i blown 3 coils. 1 msd blater 3 and 2 oem coils. the coil heats up fast and pop goes the weasel in about 1-2 mins.

im afraid to set up my new blaster coil 3. i sent ecu back and they said the ecu functions normal and the m30 base map setting are fine. what could be causing this issue? with the ignition set to "on" the coil gets 12v at the terminals. only mod to engine harness was lengthening icv, tps, gm iat, ignition coil wires. the wires are not reversed. this was confirmed with a multimeter. and ive used one for years now. Any Help is super appreciated

could a swapped cps and 6 cy ignition sensor cause this? i doubt it but want to be sure. im sure i placed them in the right spot on the harness loom by the injectors. they look like they fit one way. thats the only thing i can think off. i was quite precise during my install but maybe i made the mistake.

i finished mid June and im ready to take to tuner but need car to start and idle first.

snap shot of my ignition settings: (base map)

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below are pics of the carnage:

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demetk
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Location: CT, USA

Re: New Turbo Build Doesnt Start. Popping Coils

Post by demetk »

My guess is incorrect wiring. Are you using a ground wire on one of the terminals?
e38740imd
Posts: 430
Joined: Jun 17, 2013 12:36 AM
Location: Maryland

Re: New Turbo Build Doesnt Start. Popping Coils

Post by e38740imd »

demetk wrote: Jul 14, 2020 7:40 AM My guess is incorrect wiring. Are you using a ground wire on one of the terminals?
for the negative terminal im using the same line from the oem harness. should i be using a stand alone ground?
demetk
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Joined: Aug 09, 2007 8:58 AM
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Re: New Turbo Build Doesnt Start. Popping Coils

Post by demetk »

Make sure it's the ground wire to the ECU and not a body ground. Did it start and then blow the coils or did the coils blow when you turned the ignition on?
e38740imd
Posts: 430
Joined: Jun 17, 2013 12:36 AM
Location: Maryland

Re: New Turbo Build Doesnt Start. Popping Coils

Post by e38740imd »

demetk wrote: Jul 14, 2020 3:17 PM Make sure it's the ground wire to the ECU and not a body ground. Did it start and then blow the coils or did the coils blow when you turned the ignition on?
Car never started.

They get hot while ignition is on. During the cranking stage im guessing its not sparking. I will confirm the ground wire is the ecu ground to triple check.

I was gonna use the 179 ecu to see if this happens but cant seem to find it. Of course i was going to disconnect the boost pipe before i tried this
demetk
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Joined: Aug 09, 2007 8:58 AM
Location: CT, USA

Re: New Turbo Build Doesnt Start. Popping Coils

Post by demetk »

I can send you a 179 if you'd like to try it.
e38740imd
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Joined: Jun 17, 2013 12:36 AM
Location: Maryland

Re: New Turbo Build Doesnt Start. Popping Coils

Post by e38740imd »

demetk wrote: Jul 14, 2020 4:47 PM I can send you a 179 if you'd like to try it.
well i have dug into this issue a little bit.

so i have this issue with the ignition turned on with NO ECU plugged in. i plugged the new coil on for about 30 secs and it started to feel warm so i took the terminals off. it got real hot will disconnected so i took it off in time.

so clearly there is an issue with the engine harness some where. i looked and pin 1 is spark out on the ecu harness. i did a continuity test with pin 1 from the 55 pin harness to the negative if of the ignition coil with ignition off and it beeps. i did a continuity test on the two wires at the ignition coil ( ignition coil removed) and it beeps :? i measured voltage and it shows 12volts on plus terminal. ground on negative at all times with ignition on. s

so what could have caused this? should i get a new manual ecu harness or run new wires to the ignition coil?

i decided to open back the loom to see if there is any damaged wires and i see a small burnt or corrosion spot and continued to follow it to harness, i will have to dig in it a little later.

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i am open to suggestions. or go wasted spark? i prefer to get car running on oem ignition setup to confirm the all is ok before i jump into other stuff
tschultz
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Re: New Turbo Build Doesnt Start. Popping Coils

Post by tschultz »

I would do the same and check to make sure it is all working before trying a different system.

Are you sure you are getting 12v with the ignition on at the coil wire? Is is grounded improperly? Compare against ETM maybe...
Shadow
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Re: New Turbo Build Doesnt Start. Popping Coils

Post by Shadow »

with my ms2 coils will fire every time you turn the key and i think it's just a shitty ms thing unless you build
some circuit to prevent this. idk about with the ecu completely disconnected though.

i did blow the fuse going to the coils, do you have one?, because i switched the settings over to inverted instead of normal.
without the fuse it would've blown my coils. hope that helps.
mitch5
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Re: New Turbo Build Doesnt Start. Popping Coils

Post by mitch5 »

Nice to see my old manifold being put into action!

You mentioned that you lengthened the ignition coil wires. I would triple check that connection, on one of my cars i length ed the wires and had the exact same issues. Turned out i had some of the shielding wire touching the ground wire, always grounding it.
e38740imd
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Joined: Jun 17, 2013 12:36 AM
Location: Maryland

Re: New Turbo Build Doesnt Start. Popping Coils

Post by e38740imd »

mitch5 wrote: Jul 20, 2020 12:07 PM Nice to see my old manifold being put into action!

You mentioned that you lengthened the ignition coil wires. I would triple check that connection, on one of my cars i length ed the wires and had the exact same issues. Turned out i had some of the shielding wire touching the ground wire, always grounding it.

Good Day Mitch5!

yes that was the exact issue happening. i was on the Phone With Demetk and he mentioned the negative terminal had a sheiling which i didnt know. now i fixed the issues and the coil no longer pops with ignition on. but i am still getting no spark. i thing when i was fixing the wire issue the latest msd coil i had, it did boil and got hot but didnt pop. so i ordered an oem coil to really see. i pulled a spark plug and saw no spark. spark plug was wet from fuel which i had to blow off. so thats a sign the cps is working fine

but as im righting this. im not even sure if the cylinder head is grounded now im thinking. the block is grounded but maybe the gasket (mls) is isolating the block and the head? so i will ground the head today and see if the makes me get a spark to the plugs.


also Thanks jim for your time!. i just needed some extra insight and when we last spoke and you said sheilded wire. i already knew what i did wrong and what the issue was. :D . i now owe you a 12 pack
e38740imd
Posts: 430
Joined: Jun 17, 2013 12:36 AM
Location: Maryland

Re: New Turbo Build Doesnt Start. Popping Coils

Post by e38740imd »

the car was able to start but only for about 3 secs.

i suspects the coil is weak so i think i will have to wait until the new oem comes in

in the meantime does any one know a good place to place a ground on the cylinder head? m30b35
e38740imd
Posts: 430
Joined: Jun 17, 2013 12:36 AM
Location: Maryland

Re: New Turbo Build Doesnt Start. Popping Coils

Post by e38740imd »

i gapped the spark plugs and i notice the wire going to the ignition coil on to the distributor wasnt all the way on. :roll: :roll: i punched it in and got it to start.

only for about 15 seconds so thats still a great start. i beleive i could say i have spark and i could figure out how to make it idle. thanks for every one insight in this thread.cill make a new thread concerning idle if im not able to get it right :laugh:

you can click one the video to see it start. hopefully there is audio

edit: these is no audio!! dont know how to get it to work :roll:

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mitch5
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Location: phoenix

Re: New Turbo Build Doesnt Start. Popping Coils

Post by mitch5 »

Thats awesome to hear you got it running! Also the head typically has a grounding strap to the firewall, well atleast on my e28. Depending on how you grounded the megasquirt it could make a difference.

PID tuning the IAC can be tricky, if you search there should be some bsic settings you can find. After i had an IAC fail i just ran cracked throttle and that worked fairly well in AZ. I would almost suggest running a cracked throttle to get your fueling right at idle then return it and tune the IAC to match the rpm idle set by your cracked throttle.
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