Anyone know what is wrong with my 306??

sefw1982

Hi All

I just wondered if there was anyone on here who might have a clue why my peugeot 306 (S reg) is playing up?? It is absolutely fine starting but when cruising or decellerating in traffic the engine sputters a bit and when slowing down it struggles to idle and seems to lose power and often stalls. Accelerating is fine and the problem doesn't usually start until you have been driving for about 10 minutes, but trying to maintain a constant 40 or 50mph is a real struggle as it pulls back and forth. The problem is at its worst on hills (facing downwards) and around bends. The spark plugs have been recently checked as well as the oil - in fact somehow it just passed a service and MOT!!!

Does anyone have any advice on where to start?? It is an old car so not worth spending too much on but I can't really afford to replace it at the moment.:(

rodenal

Is it a petrol or diesel?

Assuming you have done basic head gasket checks (no mayo under oil cap, no water in oil, no oil in water - no great big cloud of blue smoke from the exhaust, see below...

The first place to start is to check for air leaks - a good way to do this is to spray carb cleaner on your inlet hoses, if the engine hunts then you have a split in that hose and it should be replaced. This should be the cheapest problem to fix.

Next thing to check is (and i'm not overly familiar with 306's so wait for further advice) Air flow meter, if it has one and lambda sensor(s) - you can do a basic voltage check on a lambda if you can get access to it, all you need is a digital multimeter. Once the car is warm the voltage should constantly vary between two set points- if it doesnt then it is probably !!!!!!ed. Also look into crank / cam position sensors

The last place I would look is your fuel pump and filter, again i'm not familiar with the 306 layout but this can either be relatively easy to swap or an absolute nightmare.

If the car has an OBD2 port then it would be worthwhile paying for a diagnostic (not from a dealer) from somebody with the right equipment.

sefw1982

Thank you very much for that. I really didn;t know where to start and as you say, no the big signs like clouds of smoke are all absent - I'll make a start with these checks this evening.

It's a 2.0 litre petrol engine.

crispy_chris

I had this with my 1.4L petrol 206.

I had so much replaced on the car I can't even remember it all now. Problem went on for about 6 months - replaced several sensors, coil pack and other various parts. Was told it *might* be the ECU. Ended up spending like £600 and it still wasn't fixed. In the end I gave up and Part ex'd it for a new Kia.

For my car at least the problem started intermittently, then got worse and worse until finally it was basically undriveable.
If you do fix it, let me know. More for idle curiosity than anything else.

[edit: just to add, its basically whenever you press the clutch down my engine would die - so traffic lights became something of a pain in the bum ]

Strider590

I had a 2 litre 306, had EXACTLY the same problem as you!

It's either the idle control valve (easy/cheap to replace £20 to £40) or more likely it's the Lambda sensor (can be anything from £50 to £200).
There's also the possibility of faulty coil pack (integrated into the engine cover).

Mine was the lambda sensor and im not kidding you, I took that car 4 different garages and NONE of them could figure out what was wrong.

One of them wanted to run engine cleaner through it, one said it was a blocked CAT, another didn't have a clue and the exhaust place (checking the CAT) actually deliberately damaged the CAT with a 3ft long screwdriver** in order to try selling me a new one! :mad::mad::mad::mad::mad:

** How do I know? (someone is bound to ask) the exhaust was fine before going there and sounded like a bag of nails when I left, then when I finally got it replaced (for considerably less than their quote), we cut the cat open and found the damage.

crispy_chris

Just to add that I replaced all of the three parts Strider mentioned and it didn't fix my car's version of this problem - although granted mine was a 206.

Strider590

crispy_chris wrote: »

Just to add that I replaced all of the three parts Strider mentioned and it didn't fix my car's version of this problem - although granted mine was a 206.

The other problem though with ALL Peugeots, they're plagued with electrical issues. The use of poor quality cable and poor quality connectors means that in fixing a fault you can actually create another one. So in your example you could change the ICV, but the very action of pulling that connector apart could have produced an unreliable connection.

And if you want to kill a Peugeot, take it for a steam clean...... Once that water gets into the connectors/wiring your driving on borrowed time.


Oh and to the OP, there's something you could try for free!!!
Disconnect the battery over night, this resets the ECU!
Unlikely to have much of an effect if there is genuine a fault, but it's free :money:

marksandsparx

After resetting the ECU, yo must drive for 30 min at all rev ranges and loads. This helps "re-learn" its parameters.

dazzadub

it could be as simple as the sensor, the one coming from the exhaust, if this has failed it could be that as that has same effect as you mentioned.

or you could had put a bit of rubbish fuel in, the same things as few years ago when tesco sold crap petrol and ruined peoples lamber sensor.

worth a look.

or

a cyclinder maybe out, or not all spark plugs are fireing, could be fuel pump, fuel filter etc could be few things

Strider590

marksandsparx wrote: »

After resetting the ECU, yo must drive for 30 min at all rev ranges and loads. This helps "re-learn" its parameters.

The 306 iirc uses the Bosch ECU, which if im not mistaken constantly learns as the engine parts wear and change with age.... However it's still recommended not to hammer the !!!!!! out of it following a reset.

sefw1982

Hi All
Thanks for all the advice. We had previously changed the idle control valve and coil pack with little success but we changed the lambda sensor as you suggested and (so far) it's worked!!! At £89 and free husband labour it was an awful lot cheaper than I had feared.