Right guys. Trying to help out a fellow dubber with their 1990 Digifant 8v MK2 Golf GTi. It's refusing to start, but will start with a bump start. Starter motor seems to be cranking the engine ok. So far - * We are getting spark from all 4 leads and the kind lead from the coil * Fuel pumps are priming ok when ignition is started * Cylinder and plugs are wet with fuel * Tried a brand new Bosch battery from Euro, still the same * Plugs look ok. A little black but nothing too bad * Dizzy and rotor arm look ok What else could I look for ? It's had a head gasket change in the past. Knock sensor looks a little worn. Any help would be great. Cheers.
Could this be a possibility, even though the engine is cranking over ok. Also, it seems to be ok at the moment. Seems to start ok after a bump start. But then sometimes will only crank over ?
Could this be a possibility ............ Just not sure anymore ..two things came to mind when I read your topic. It was the ign switch or the flux capacitor "even though the engine is cranking over ok." it losses feed to ign terminal ..burn worn switch
turn ign on ..all lights ..pop bonnet main feed to your starter bit of wire from it to starter solenoid terminal car should crank and start (health & safety) check car is not in gear you just need to touch a feed on the red/black wire on ign switch plug ..with ign on leek have you never stole a car Rick
Guys, we haven't tested the igntion switch yet, but could a faulty blue temp sensor cause these kind of running issues ?
it could well be the switch, sometimes they fail in such a way they cannot supply the coil with enough voltage while the engine is cranking over. easy test for that is run a wire from battery + to coil +, if it fires up perfectly every time then check the ign switch and wiring to it. top suspect for this apart from switch is ropey old alarm or immobiliser, or bodged up wiring to ignition switch due to the above. it may even be the blue sender starting to pack in, they can fail in mysterious ways. on mine it woudl never ever fire on the 1st turn of key, no matter how long I cranked it for. 2nd crank perfect start and run, every time. scratched my head for a while and tried a new blue sender, fixed! have a listen out next time for the fuel pump runnign while the engien is cranking over also, and just have a good look over the wiring. by the sounds of it since you have intermittent fault its a case of something almost, but not fully broken. which is the most fun kind of problem to find a good one is a pin inside one of the sensors that is slightly out of shape or pushed out of position, so pop all the plugs off and check, and any that have a rubber boot on peel it back to check wires underneath
I' definately give this a wirl, quick test and its free. I suppose the other thing to check for is compression.
When you say the plugs and cylinders are wet with fuel reminds me of a problem I had with the ECU. When you say the pumps prime OK, do they stop after a few seconds if the engine isn't started? If not it's likely a bad earth has fried the ECU.
I wonder if there's a poor connection, or degraded cable going to the starter? (Positive or ground). This might explain why, even with a brand spankers battery, it's not having it via the starter, but will go with a bump. I recently had an issue with a dodgy alternator volt reg, which made my battery gradually flatten over the winter. The difference between starting with and without an external charger having been put on the battery was stark. Yet I hadn't noticed any difference in cranking speed.
I wonder if there's a poor connection, or degraded cable going to the starter? (Positive or ground) no topic states ... Starter motor seems to be cranking the engine ok. This might explain why, even with a brand spankers battery, it's not having it via the starter, but will go with a bump. again ..Starter motor seems to be cranking the engine ok. your trying to explain a problem that isn't there.
We'll see. The key word for me is italicised here: "The starter motor seems to be cranking the engine OK".
