TheLarneMan 4 Posted September 4, 2007 Has anyone experienced problems with interference and their Emerald M3DK ECU? Mine seems to be losing the signal from the crank sensor. It only happens after about 5 minutes of driving after starting the car from cold. After the 5 minutes, the car looses all power for a split second then it works normally for a bit. This continuosly gets worse until it starts to misfire causing explosions and pops from the exhaust. All relevant components have been renewed/swapped with known good parts - crank sensor, leads, plugs, battery, coil, even the ECU. As everything has been replaced, Emerald are suggesting something is interfering with the ECU. I can't understand how the interference only starts after about 5 minutes and is not constant from the moment I turn the key. At present the ECU is located in the engine bay (behind the passenger side headlight), but I'm in the process of getting a new loom made and moving the ECU inside the cabin. The car is a 1990 205 GTI with an Mi16 engine and Jenvey throttle bodies if that makes any difference. The throttle bodies with ECU (and new loom) is a new setup for me and has never actually worked properly! Everything was fine when the engine was standard with the original Mi16 ECU and loom. All suggestions welcomed. Cheers. Share this post Link to post Share on other sites
kyepan 291 Posted September 4, 2007 engine water temperature perhaps, as that stabilises after five minutes. or some other component coming up to temperature and then going bansai I've a heat related problem, turn the key after going for a long drive, nothing, but its fine from cold, give it 20 mins to cool and it goes. think i've narrowed it to one of the relays in the glove box fuse board J Share this post Link to post Share on other sites
pdd144c 0 Posted September 4, 2007 Take it your crank sensor wiring is screened correctly? Have you had your laptop connected in the car when it happens to see if any of the readings are odd? Share this post Link to post Share on other sites
TheLarneMan 4 Posted September 4, 2007 My first thought was water temp or something else heating up (e.g. spark plugs) but I can't find any problems. Yeah, the laptop has been plugged in while the car was running and no odd readings appeared. An o-scope also showed no glitches. I'm almost sure the crank sensor wires are shielded - will need to confirm. Share this post Link to post Share on other sites
kyepan 291 Posted September 4, 2007 so the timing goes completely dolally, can you wire the scope up to the crank sensor when it gets hot to check its pulsing at the right time? Share this post Link to post Share on other sites
TheLarneMan 4 Posted September 4, 2007 The o-scope showed no problems whatsoever! Share this post Link to post Share on other sites
Craigb 2 Posted September 5, 2007 Can you post your settings for idle control etc. Set the data log to record rpm , injector pulse , and ignition timing , and see if you can post the output file . Also have you configured the distributor / crank sensor correctly , I had issue with this , the ECU was expecting one type and was getting a different type , it didn't like it ! Share this post Link to post Share on other sites
Dream Weaver 2 Posted September 5, 2007 The screening wire is only earthed at the ECU isn't it? And does it run away from any other sensor wiring? Share this post Link to post Share on other sites
TheLarneMan 4 Posted October 18, 2007 Thanks for all the suggestions. Problem solved. The ECU was relocated from the engine bay to inside the cabin and all is well. Case closed! Share this post Link to post Share on other sites