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325 non start no spark
Posted: Tue Jul 01, 2014 6:49 pm
by Olley
325 M20, wont start, got fuel but no spark. no power to coil. anyone got a clear wiring diagram or knows the colours and where they go?
car turns over ok. but the wiring is a bit hit and miss. done manual conversion so all auto loom removed, and has after market alarm that has been bypassed. any and all help appreciated.
Re: 325 non start no spark
Posted: Tue Jul 01, 2014 6:52 pm
by Speedtouch
Re: 325 non start no spark
Posted: Tue Jul 01, 2014 6:59 pm
by Grrrmachine
Green wire would be my bet, especially if this used to be an auto:
http://www.e30zone.net/e30zonewiki/inde ... oubleshoot
Re: 325 non start no spark
Posted: Tue Jul 01, 2014 7:47 pm
by Olley
Got 12v at C101 pin 7. going to have a look through the interwebs about what wires need connecting to bypass the inhibitor switch on autos. proper confused as i had it running. took the engine and box out to change the clutch, dropped it back in and now it wont start.
can't start it now as it's too late. but will be back on it in the morning. if anyone fancies popping by to give me a quick hand feel free!
Re: 325 non start no spark
Posted: Tue Jul 01, 2014 9:16 pm
by Brianmoooore
If the engine cranks, then the auto inhibit is bypassed.
Are you absolutely sure that the fuel pump runs when you crank the engine?
Remove a spark plug after cranking and see if it is wet with fuel.
Re: 325 non start no spark
Posted: Tue Jul 01, 2014 11:28 pm
by Olley
I'm sure the fuel pump is going. i can hear it, and the first time i tried to start it, there was a 4 foot fountain of fuel spraying out of a split in the pipe! which is now fixed.
had a look on a thread for trans swaps, and it showed some plugs under the centre console that were different to mine. so might have an issue there, I'm just so baffled because i had it going before i took it out to change the clutch...

Re: 325 non start no spark
Posted: Wed Jul 02, 2014 12:28 am
by Brianmoooore
Brianmoooore wrote:
Remove a spark plug after cranking and see if it is wet with fuel.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 12:44 am
by Olley
Point taken, will have a go in the morning.
what would be the likely cause if no fuel through the injectors and no spark?
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 6:43 am
by Grrrmachine
Olley wrote:what would be the likely cause if no fuel through the injectors and no spark?
http://www.e30zone.net/e30zonewiki/inde ... ion_Sensor
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 9:52 am
by Brianmoooore
No fuel through the injectors (with fuel pressure present) and no spark would be a very unusual scenario, and wouldn't be caused by a duff CPS.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 12:00 pm
by Speedtouch
Has the engine-to-body earth strap been reconnected securely?
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 1:53 pm
by Brianmoooore
Are you checking the spark at the king lead or at a spark plug? If at a plug, is it one spark every two turns of the crankshaft?
We've had cases on here where the problem has turned out to be a broken cam belt!
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 1:56 pm
by Olley
spun the engine over with oil filler cap off and looks to me that cam is spinning ok, no voltage to the coil itself. been out ordering parts this morning will get on it now! but if someone is nearby NW london, it'd be hugely appreciated!
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 1:58 pm
by Olley
forgot to add, the fuel pump was being "hotwired" so power straight to it.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 2:06 pm
by Brianmoooore
Olley wrote:forgot to add, the fuel pump was being "hotwired" so power straight to it.
That does make rather a significant difference!!!!!!!!!!!!
Does that mean you don't have fuel pump activity then?
If not, disconnect the crank sensor plug and measure its resistance.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 2:06 pm
by Speedtouch
Try hooking a lead directly from battery +12V to the + side of the coil, to at least establish if the engine runs.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 2:08 pm
by Olley
tried putting 12v to coil and it still didn't kick into life, turns over, but doesn't fire.
what resistance should i get across CPS?
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 2:10 pm
by Speedtouch
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 2:19 pm
by Olley
Got 520 ohms.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 2:30 pm
by Speedtouch
Sounds healthy enough.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 2:43 pm
by Olley
My bad! had the three plugs wrong for ICV, CPS and the one that goes to #6 HT.
she fires and runs but runs like a cammed V8, except she wont rev up. just hesitates and cuts out.
at least i know it runs! time to get on with the rest of the project! cheers guys!
videos when it's done!

Re: 325 non start no spark
Posted: Wed Jul 02, 2014 3:18 pm
by Speedtouch
Hehe, that would explain it. Could be the ICV in need of cleaning, or the TPS needs setting up.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 3:28 pm
by Olley
Well, it's on a "new" ECU from a manual car, so I'm guessing the ECU will need to learn the car a bit, also, no coolant system on the car so can't run it for more than a few minutes. Can I put a link to a website on here for purchasing bits and pieces? I highly recommend this particular site, as it is cheap and the free delivery took less than 24 hours...
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 3:44 pm
by Speedtouch
Yes, you should let the engine idle for at least 10 minutes to enable base idle settings to be learnt, then switch off, then drive it throughout the rev range to ensure full transfer of data from the EPROM to the processor.
Re: 325 non start no spark
Posted: Wed Jul 02, 2014 3:47 pm
by Olley
Cheers, will get the rest of the car put together then let the ECU learn.
Cheers for all the advice!