Hi folks i have a 1991 mk2 golf gti 8v digifant engine (ce2) and over the past few months the car has been starting very inconsistently. One morning it may start first time, the next morning it might be after 10-15 turns, sometimes i need to give it a bump start to get it going, and other times it just will not start at all! The fuel relay clicks as normal and primes almost everytime (sometimes it doesnt but i think the system has enough pressure at this point that it shouldnt need to prime?? this is usually after a few turns of the key one after the other...) So i thought i am not getting a consistent spark, so i changed the TCI unit, the coil, changed the distributor for a full brand new VW gen one, changed the plugs and plug leads, changed fusebox and also removed the immobiliser/alarm system as it was getting old.. Still nothing. she fires up sometimes and when she does she drives sweet and doesn't miss a beat, there has been a couple times where the engine has cut out but this was down to the hall sender which has since been replaced with the new dizzy. I am really not sure where to with this iv checked earth wires they all seem fine and must be okay if the car starts up sometimes?? Iv read that components inside the ECU can fry and melt and this can cause intermittent problems?? i will need to look into this still but is there any advice anyone can offer? i need the car running again as its my daily driver and recently iv been relegated to driving my mums fiat 500 which is S**T! any responses and advice welcomed and appreciated cheers, DAZ
Hi Pete thanks for the reply, I should have mentioned, the blue temp sender was renewed within the last 6 months to a year, it was a non gen one bearing in mind, but when the engine does start it idles and runs fine which would suggest the temp sender is okay? Thanks Daz
Before you go thinking a blown ECU, a very common issue with 20 year old Mk2's is a worn ignition. Bunches of keys dangling from it, who knows how many times it has been switched??? I had a Mk2 that failed to start on me at a filling station. I was just that, faultlessly starting everyday then this. Providing all your dash lights are in operating order, a quick check to reveal a dodgy switch is: With the key in the OFF position - NO warning lights on, Key in ON position - Charge & Oil pressure warning light ON, Key in CRANK position - Charge light ON, Oil pressure light ON/ Going OFF once oil pressure is reached. If BOTH warning lights go off in the CRANK position it is quite possible the switch is duff. I'm no electrical guru and I'm sure there must be info about in an advanced search. It's seem as even though you are getting it to crank on the starter, there's a live feed loosing its signal in the cranking position.
Simple check for a blown ECU is when you hear the fuel pump prime does it last a few seconds or carry on? If it carries on it's a classic sign of a blown ECU.
