People Gti 125 won't start

[Ruffus]

Pls try this


-when your injector is out and in a container, switch ignition on (you should hear the fuel pump running for about 10 secs) and watch whether you injector is dripping. IT SHOULD NOT drip, only with ignition on and pump running.
If its drips, some grain is in your injector nozzle

This airfilter looks...hmmh
check, is there any possibility that, from your fuel line some fuel is leaking into this suction tract.and swamps your intake system?

[Faber32]

I did like you say. Ignition on, injector out and I watched it for a couple of minutes. No dripping.
I give up, I'll go to the dealer. My fear is that too much gas enters combustion chamber for a timing issue or there's a weak spark because ignition coil is not good enough to send a high voltage. It's a difficult diagnosis.

I'll let you know and thanks again

[CROSSBOLT]

I did like you say. Ignition on, injector out and I watched it for a couple of minutes. No dripping.
I give up, I'll go to the dealer. My fear is that too much gas enters combustion chamber for a timing issue or there's a weak spark because ignition coil is not good enough to send a high voltage. It's a difficult diagnosis.

I'll let you know and thanks again

Bring lotsa money.....

[Ruffus]

@Faber32,
I still think there is a simple cause behind this phenomenon. Before you see your dealer, pls check valves again and the fuel delivery chain from gas tank until injector. Gas must somehow, sonewhen enter your cylinder and wet the sparkplug otherwise we would not see it on endoscopes pics.
Would really love to put hands-on.
Weak sparkplug Im inclined to exclude, 'cause its running when started.
Timing issue, so-so, but runs fine.
Whatever you find out, pls tell us.
Maybe you write down in bullets.what you did
to make your mechanics life easier and search shorter $$.

[Faber32]

Thanks again.

I just let it to an indy in the end. Unfortunately I didn't have time to do attempts anymore, I felt I was at an impasse. I adjusted valves very carefully with a professional gauge, I don't think I could have done big mistakes. Probably I should have checked if the injector leaks watching it for hours and not only minutes. It's possible that it drips very slowly. This morning same story: didn't start, then I dried the plug and boom, start at first shot perfectly. I'll let you know soon

Question: if it's the injector faulty, is it sufficient to detach it from fuel hose line and replace it? What about air trapped in the hose at first start? Doesn't it damage the injector? There's a way to purge air before starting the engine with new injector?

[Ruffus]

No, it does not matter at all if you had your injector removed.
This little air in it is easily compressed by fuel via fuelpump. Evaporates then through valve and off.
But would really love to know the outcome.

[Faber32]

For sure, I'll let you know 

[Faber32]

Bad news. Suspect head gasket burned. I don't know if I will repair it. The mechanic says it was water getting the plug wet.

[scooterfan]

Bad news. Suspect head gasket burned. I don't know if I will repair it. The mechanic says it was water getting the plug wet.

One good reason to stick to air cooled carborettor models.

This thread just confirmed what I firmly beleive in - just stick to air cooled carborettor models and you will never experience such nonsense.

[Iahawk]

interesting..so all along the assumption was that the liquid in the cylinder was fuel when in reality it was engine coolant?

[Faber32]

Exactly. And considering how rapidly the plug gets wet, I think the damage is quite evident.

Honestly I don't know if it's an issue that happens or if it's due to short trips or what. Anyway I'll repair it, next big issue I give it away :-)

[Ruffus]

Sorry to hear, but on the other hand, a headgasket repair is not that big issue. I don't think your cylinderhead or any imminent parts have suffered too much, for it would not run properly.
Thanks for your review.

[Faber32]

Thank you :-) mechanic asked me about 440 dollars. I told him to proceed

[Ruffus]

Faber32, what a coincidence, I'm living in Italy regione(FVG) Udine, too.

[Ruffus]

Just recently bought a LIKE 200i from Spinea and drove it home to Aquileia. Chi vediamo. Mandi
If your are by happenstance in my area, AQUILEIA (UD) send me a PM.