I have rebuilt the engine in my Mk2 GTi 8v (PB) but it wont turn over. Everything is connected, fuel etc is all good. Now, when I first turned it on the key it cranked for about 3 seconds but really slowly. Then it wouldnt crank at all. Left if a few minutes and it did the same thing. At this point I had all the dash lights that you have on start up. After this it wouldnt even crank, there is 12v+ in the battery. I moved the gearbox earth strap to the starter mount where it meets the engine block. Still nothing. Moved it back and for some reason now, I have no dash lights, it still wont crank but unless i disconnect the battery the handbrake light stays on - as does the full beam light but really dim (and full beam isnt on). Royally confused. Anyone got any ideas? Dan
Right, left it 10 minutes - Now she cranks, and the dash lights are back to normal but still wont fire up - I can smell fuel so I can only assume I am not getting a spark I hate cars
how much do you know about the battery!! it might show 12v on a meter but might not have the juice to crank, all batteries will gain a few volts if left like that, might be worth chucking another on or a set of jump leads to illiminate the battery. keep us posted, then we can sort it
I did electronics at A Level - I didnt bother posting all the info about the battery It has enough cranking volts and enough current to spark but its not getting any for some reason. As i said in the last, the car now turns over fine, it just wont fire - The problem with the dash lights was the gearbox earth.
hmm does the fuel pump stop priming with the ignition on? it should stop after a few seconds. if not...ecu blown. the timing 180 deg out? or slightly off?
I'll try the ignition in a sec but im pretty sure it stops. Timing should be fine, when you earth the HT lead you dont get a spark so Its not sparking at all, not just at the wrong time. Ive just had a thought though, I dont remember plugging the throttle position microswitches in - Would that cause a non-starter?
Are you certain that you have timed the cam up correctly? Having cam timing out would potentially cause the cranking issue you have described but not the electrical issues.
It was TDC when I timed it up, when turning over by hand they all matched up - If it was the cam timing, surely i would still be getting a spark at some point, albeit at the wrong time? Or am i mistaken? Ive just got outside, yes the fuel pump stops priming after a few seconds. The throttle microswitches werent plugged in, plugged it in and still nothing [:^(]
I was going by the fact that you said it only cranked for a few seconds really slowly and now cranks no problem at all....just ringing some alarm bells! Yes you would still get a spark for sure....can you check something quickly to rule out any issue with cambelt (unlikely that it is)....disconnect the plug at the dizzy, remove cap and make sure that the rotor arm is turning as you crank it over.
Oh I should be more thorough with my replies tbh The problem with the funky dash lights to begin with and the cranking them stopping was the gearbox earth - Where I had painted the gearbox, i hadnt removed enough paint to make a good connection but that is sorted now. I will go and check that now
[YOUTUBE][/YOUTUBE] ECU should be fine, it was strong before the engine came out and it hasnt been touched at all - Im going to test the coil solinoid tomorrow and test the king lead to see if that is causing it. Do you or anyone know which sensors, when broken or unplugged - Stop the car getting a spark?
So when you turn the key to position number 1 (Acc) The battery light and oil light illuminate, yes? When you go to crank it, are the lights still on or do they go out? The oil light might go out when sufficient oil pressure is achieved? Could be dodgy ignition switch! U could also eliminate the ignition barrel by placing the car in neutral, turning the ignition on into the 1st position. Then by using a 'jump wire' (roughly 600mm) with a 6mm female spade terminal on 1 end. Disconnect the wire to your starter solenoid and fit your 'jump wire' in its place. Now touch the other end to the positive terminal of your battery and see if it starts. Ignition barrels on these cars seem to have a good switching life of about 20 years! Just a suggestion!
All the lights act as they should when you crank it over, and it cranks over fine - The starter turns on every turn on the switch it simply will not fire. The ignition barrel was fine before I took the engine out and hasnt been touched since
I seem to recall that a bad earth can cause a short that will blow the ECU....I know this happened to me on my Mk4 1.8T. I suggest you drop a PM to rubjohnny as he is the best person I know on here for wiring and electrical issues
No spark would lead me to the coil. Ive found with a blown ecu these engines still spark. Ive had the cam timing slightly off once which caused the engine to turn slower/stop turning (with spark plugs in) Also are you sure the piston is at Top Dead Centre? remove spark 1 and put a screw driver down the hole. The piston should be at the top.
I will test that tomorrow but I am fairly confident that the timing is ok. Ive just had a thought though which someone might be able to help me with. When I took the engine out, the nut on the rocker cover ground plate was just spinning, and before I had a chance to figure out what I was going to do about it - My mate took a pair of snips to it Now when i put the engine back in, ive put (what i think is the same wire) back on with a new crimp. Its a black wire, but i did notice today that on the coil, their is a connector on it with no wire. It is the connector that is on the side of the coil facing the front of the car. My only problem is, that if it goes their - Where is the earth wire Anyone able to help?
As per my post above I would suggest you contact rubjohnny for any electrical queries as he has a wealth of knowledge. My gut instinct is still leaning towards ECU as you had a knackered earth and tried to start....but I could be wrong as my knowledge of Digi is somewhat limited I'm afraid.
I'll give everything a test later this evening, if all fails I will send him a PM. Cheers for the suggestion. The only query I have with it being the ECU is that the earth wasn't shorted, it was just simply not connected. Am I right in thinking that on these engines, the hall sender also controls the fuel so if that was faulty, I wouldnt be getting fuel either? Dan
