Peugeot 307, petrol engine: cranks but does not start - trouble getting OBD diagnostics

[Bescheiden]

Yesterday I drove normally when I heard a very small noise, like maybe a plastic part came loose and was clattering. From the engine compartment. I stopped, then the engine stopped by itself, and I haven't been able to start it since.

In retrospect, the engine did not always start immediately, it sometimes took one or two seconds longer, and not only when it's cold.

Trying to start the engine sounds normal otherwise, but there is no combustion.
Jump-starting (downhill, then 2nd gear) did nothing either.

After cranking many times, the battery is now low but not dead.

There's a little blue knob behind the engine covering a valve, pressing it squirts fuel, so I'm guessing there's pressure on the line.
The cooling water was very low but not empty; I have filled it up now.

I have never had problems with the engine. I changed spark plugs and oil about a year ago. I changed the long exhaust pipe and the exhaust itself just before this happened.

I borrowed a cheap OBD reader, it connects (KWB FAST init protocol) and seems to be working (tests connecting to the internals give results) but each time I start the diagnostic it almost immediately returns "No emission-related DTC found". I have no idea if this is a s**t product's internal error message or the car's. I am telling the device to get all DTCs.

Is there any way I can find out what's going on? Thanks in advance.

[Bescheiden]

The battery is charged now.

Unfortunately, it didn't do anything to the OBD reader. This is how it looks both now and in the past:



So apparently it doesn't find any error codes.
I wonder if it's the meter or the car.

Engine:



Is the timing belt inside that plastic case? Is it possible to check its condition without completely disassembling it?

How can I check that the fuel reaches the engine? There is a blue knob behind the engine, there is a valve under it, I pressed it, gasoline splattered. The tank gauge shows 1/2.

[myglaren]

So apparently it doesn't find any error codes.
I wonder if it's the meter or the car.

Have you access to another car, ideally a similar one, that you can try and read the codes from?

[Bescheiden]

Good idea, thanks! That will be my next step.

[wheeler]

The timing belt is under that cover, the easiest way to make sure its not completely snapped is to remove the oil cap & get someone to try starting the car see if the camshaft is turning.
Does the diag tool read live data? can you see engine RPM?

[wheeler]

looks to me like your OBD tool is connecting but showing there is no fault codes? not every scenario that will cause a non start situation will log a fault code.

[PaulC5]

looks to me like your OBD tool is connecting but showing there is no fault codes? not every scenario that will cause a non start situation will log a fault code.

I think an example of this could be a fault with the crank shaft sensor.

[wheeler]

Exactly, no engine RPM reading = no spark & no fuel being injected.

[Bescheiden]

The timing belt is under that cover, the easiest way to make sure its not completely snapped is to remove the oil cap & get someone to try starting the car see if the camshaft is turning.
Does the diag tool read live data? can you see engine RPM?

Re oilcap: I can't get any help at the moment. I tried with my phone, but it cannot look sideways into the whole, and from the top I see no movement at all.
The tool reads live data though! RPM goes to just under 200rpm when cranking. Does this mean the timing belt is not snapped?

looks to me like your OBD tool is connecting but showing there is no fault codes?

That's my interpretation too. Maybe the module does not work or the car is too old.
I can get some data - just no DTCs

I think an example of this could be a fault with the crank shaft sensor.

What do you mean? That the crank shaft might be broken or the sensor that reports that?

[wheeler]

Thats good that you can see engine RPM but does not mean the timing belt is not snapped. Engine RPM is measured off the crankshaft which will still turn with a snapped timing belt.

[PaulC5]

Instead of using the starter to turn the engine, you can put it in say second gear with the handbrake off with the ignition key removed from the car. Then give the car a push whilst looking in the oil filler cap hole to see if the cam shaft turns so it only needs one person.

Seeing 200 rpm might not be enough to start it but it can mean the crank shaft sensor is not faulty.

[Bescheiden]

Seeing 200 rpm might not be enough to start it but it can mean the crank shaft sensor is not faulty.

This was just a short cranking; I'm afraid to break something if I crank longer. It might well have gone far above otherwise.

Anyhow, I learned that the engine is of the type where I cannot see any movement inside even after taking the oil cap of - there's yet another plastic cover.

Still investigating...

[wheeler]

Anyhow, I learned that the engine is of the type where I cannot see any movement inside even after taking the oil cap of - there's yet another plastic cover.

OK, may me easier to just undo the 3 screws on the top timing cover & pull it back for a look.

[Bescheiden]

Firt of all thanks for all replies, I really got some help and insight.

I brought the car to a mechanic and his diagnosis is that the timing belt is loose and most likely jumped and misaligned the valves (I'm probably saying this wrong).
He says there's a chance that changing the belt will fix the issue, but there's alos a (big) chance that the valves are damaged.

My question:

How likely is it that the valves are (fatally) damaged if I immediately noticed the belt jump, stopped the car within ~100m, the engine died and never started again?