GTi-6 Head Gasket Failure?

[khj100]

Hi all,

Sorry to join up and launch straight in with a brainteaser, but I was hoping for some advice and the benefit of your experience.

First of all the problem; I have a Peugeot 306 GTi-6. It's done 92,000 miles, and tolerated my "enthusiastic" driving (and a few trackdays) for the last 50k of those... It's been fully serviced, and had absolutely everything it needed.

About 3 weeks ago it developed a bad starting problem... It struggles to fire, seems immediately to be overfuelling, and obviously very quickly floods completely. Difficulty seems to be related to the length of time it's been left.

When it is running, it runs absolutely fine. Definitely no lack of power, no immediate signs of any failure etc.

I have replaced EVERYTHING i can think of (all sensors, ECU, injectors, coilpacks, plugs, entire throttle body... - the list goes on!) all to no avail.

Another member of the 306GTi6.com forum had experienced a similar problem, with ultimated turned out to be head gasket, so I have to consider this.

That said, I have;
- good compressions on all 4 cylinders (c. 190psi),
- no major evidence of water > oil contamination (just a bit of build up when the engine is first run),
- no evidence of coolant level loss (although there is [i]possibly[/i] a slight problem with a recurrent airlock - this might just be my paranoia)
- absolutely no steam out of the exhaust once warm, under any kind of driving condition - high revs, low revs, overrun etc.....
- definitely not got a drop in performance

I am ready for the worse, and by a process of elimination I'm considering the HG as a serious contender...

(my theory being there might be coolant getting into a cylinder whilst the coolant pressure remains high and the engine starts to cool, making it hard to start if it's been left a while)

....but I just can't bring myself to take the head off and investigate when I'm not seeing ANY [i]major[/i] symptoms. But on the contrary, if it could be that then I've got a chance to replace before it blows for 'real' and takes warps the head along with it...

So i'm particular interested to know
- has anyone ever seen a head gasket failure with no, or only very, very subtle symptoms?
- if yes, what symptoms would you expect to see first?
- if no, can anyone think of anything i've not yet tried?

Thanks in advance for any thoughts or experience anyone's got of a similar problem.

Cheers,
Kev

[Matt_FP]

Seen similar to what you describe, coolant leaking into cyls overnight causing starting issues. Although you would expect loss of coolant.

Word of warning though the GTI-6 heads warp to the point of being useless when you un-bolt them. You need (IIRC) aa pug frame which bolts onto the head and holds it straight whilst the headbolts are undone.

Matt

[khj100]

Matt,

Thanks for the reply. That's as I feared. When you've seen those symptoms, have they affected any other aspect of the car/performance (like the ones I listed?). If not, how rapidly has it 'developed' into something a little more identifiable?

I've heard of the problem with heads warping on removal too - I'm hoping that, if it is the cause, I could escape massive problems as I've caught it before it's overheated.... Will look into this locking device though too!

Sorry for all the questions!

I'm in a proper Catch-22 though. Take the head off, risk warping, realising it wasn't that, and cursing myself.... Or leave it, let it develop, realise it WAS that, the gaskets blown, I've knackered my head and end up cursing myself again! AAARGH!

More thoughts from others still very welcome!

Kev