Wierd engine behaviour 1999 306 XSI 16v 1998cc.......

Expert opinions urgently required.....

My 1999 (T-reg) 1998cc 16v Peugeot 306 XSI has a wierd engine
characteristic that I’m a bit baffled by. It only seems to happen
when the car has been running for half an hour or longer, and seems to
come and go a lot. I suspect it’s to do with the fuelling. When it’s
misbehaving, the engine is very hesitant, it takes a few seconds to
respond to the throttle, even when out of gear, and the engine seems
to have difficulty in responding to changes in engine speed, e.g. when
changing down to a lower gear and pressing the accelerator I get a
hesitation that can last a couple of seconds before the engine pulls
forward in a rather lumpy manner. This never happens within the first
20 minutes of any journey, and the car might behave normally if it
gets to remain at the same engine speed e.g. when cruising along the
motorway for an hour. On Tuesday it was fine on a long motorway
journey until I hit stop-start traffic and it started misbehaving, it
got got so bad that the engine started stalling when left to idle.
Whenever I started the engine following a stall it would start on the
button and behave normally for a few seconds (presumably until the
automatic choke turned itself off) and then would go back to
misbehaving. Then on one particular occasion when the engine cut out
when I was changing between gears at about 25mph I just dropped the
clutch into 2nd gear and bump started the engine, it spluttered and
lurched into life and the problem instantly disappeared for the rest
of the journey (but this problem still occurs at the moment just as it
did before).

Any ideas what this could be? I’m baffled because it only seems to
happen when the engine is hot, and i’m confused at how bump-starting
the engine temporarily cleared it on Tuesday - I’ve thought it could
be a clogged/collapsed cat, or a ropey lambda sensor - Any other ideas
what it might be? The car has done 100k miles by the way, it makes a
bit of a tappy/ticky noise at 2k+ RPM but i’m told this is common on
306s and is probably just noisy fuel injectors........

 

Anyone????

 

i no this sounds simple but have you checked the spark plugs as ive had one
with the same kind od fault and it had ngk single electrode plugs in it
instead of multi point replaced them and it cured the fault got to be
worth a try

 

Check *ALL* the pipes in the engine bay for leaks. My 2.0 8v 405 had a split
vacuum pipe from Manifold to MAP Sensor, and it had very similar symptoms.

 

The pipes all look okay, not corroded or anything. I’m going to have
a bash at changing the lambda this weekend if the weather’s good.
Does anyone know where to find the MAP sensor in a ’99 306 xsi? Are
they easy to change?

 

There is a ton of people with the same problem on 1.8 and 2.0 16V motors on
different cars (306,406..) Far as I know (and I am following all the forums
because I am pissed of with this situatuion) nowbody knows what is the
reason. There are different theories (stepper moror, ignition coil, low
voltage, Sagem or Bosch ECU...) but some of the people with this problem
already changed all this parts (!!) and they are still strugling with the
same problem. I am planning to write a letter to the Peugeot headquarters
with enclosed all the mails from formums and discuusion pages. If you are
willing to write one (I am from Croatia and my English is not perfect) i
will supply you with the copies of most of the topics about this theme.