306 1.4 LX jerks when pulling off.

pug_owner2002 · Post by **pug_owner2002** » 10 Jan 2007, 12:52

Hello All,

I have just got a 2001 (X reg) 306 1.4 LX (not sure which engine code this is?), which jerks when pulling off and doesn't feel as smooth as I thought it should when accelerating.
The car used to be my mums and it's done this for quite a while, it has 90k on the clock and a full Peugeot dealer service history.
Could this problem be the common fault of the EGR valve being bunged up?
If not what else would you suggest I check
Any help appreciated, Thanks.

pug_owner2002 · Post by **pug_owner2002** » 20 Jan 2007, 17:28

Well I have had another look to try and find this problem and whilst at it sorted out the exhaust which had a hole in it, now that the middle pipe has been replaced it does feel a bit better but still has this jerk when pulling off, which I can only describe as the car pulling off, hesitating and then finding the power again.
I was going to change the HT leads but it would appear that this engine does not have them, just a black box that sits on top of all of the spark plugs.??
I want my diesel back

PowerLee · Post by **PowerLee** » 20 Jan 2007, 17:34

pug_owner2002 wrote:Well I have had another look to try and find this problem and whilst at it sorted out the exhaust which had a hole in it, now that the middle pipe has been replaced it does feel a bit better but still has this jerk when pulling off, which I can only describe as the car pulling off, hesitating and then finding the power again.
I was going to change the HT leads but it would appear that this engine does not have them, just a black box that sits on top of all of the spark plugs.??
I want my diesel back

That black box you mention is the coil pack, A lot of cars have the coil pack or individual coils bolted straight on top of the plugs now, no need for HT leads.

This coil pack, isnt made by SAGEM by any chance? Have a good look for a makers name

Hopefully fingers crossed it wont be a SAGEM coil pack

pug_owner2002 · Post by **pug_owner2002** » 21 Jan 2007, 14:06

Hi PowerLee,

I've just had a look and my car has got the Bougicord coil pack fitted.
Could this still be the cause?
I'm not sure if that is the original coil pack as when my mum first had the car it kept loosing power and then coming back to life, it wouldn't tick over and then when restarted it would tick over. As the car was only 10 months old it went back in under warranty, the peugeot dealership said that they only replaced the spark plugs but I cant belive that the plugs would have made it run like that.
Also I have noticed that if I start it in the morning and blip the throttle the car almost cuts out when you take your foot off, another thing I have noticed is when I turn the engine off I can hear a ticking noise like a stepper motor, this noise comes from a unit that is on the air pipe at the top of the engine, is this normal?

Has this car got an EGR valve? if so where is it as I would like to blank it off as I have done the on the girlfriends astra and it has made it run miles better and the way the pug runs reminds me of how the astra was prior to the EGR valve being blanked off.

Any help is much appreciated!

PowerLee · Post by **PowerLee** » 21 Jan 2007, 14:44

A Bougicord coil pack is fine

Sounds like its been replaced sometime in its life.

I would take the stepper motor off ( 2 x torx 20 screws, dont lose the O ring ) & clean the plunger & also the air bypass hole the plunger sits in ( cotten buds are perfect for this task )

This ticking unit, isnt brown in colour by any chance & made by Bosch towards the left hand corner of engine bay?

EGR valve, I would think it has somewhere but dont quote me on that.

wheeler · Post by **wheeler** » 21 Jan 2007, 23:22

pug_owner2002 wrote:Has this car got an EGR valve?

No this engine doesent have EGR.

pug_owner2002 · Post by **pug_owner2002** » 25 Jan 2007, 12:36

Thanks for the replys,

The unit that makes the ticking noise is black in colour and appears to be screwwed to the side of the air pipe at the top of the engine by the fuel injectors.

pug_owner2002 · Post by **pug_owner2002** » 15 Feb 2007, 12:47

Hello,

Just an update, I have checked all of the breather hoses etc and they are all clear. I am starting to think that the automatic choke is playing up as when the car has been stood all day or over night it will cut out as you go to pull off and if you feel that it is about to cut out and try to give it some revs it splutters and nearly dies.
Does anyone have any ideas about this?

Thanks.

Post by **philhoward** » 15 Feb 2007, 20:11

Its fuel injection, so won't have an automatic choke as such - what might affect it is if the engine temperature sensor has failed (not the one which is used for the temperature gauge, but probably in the same area). If it fails, the engine sends to run in "limp home" mode, and substitutes a reading of its own. It's not optimum, but should allow the engine to run, even if badly - even from cold.

AndersDK · Post by **AndersDK** » 15 Feb 2007, 21:13

I'm with Phil here.

The engine temp sensor is used by the ECU to determine which degree of "choke" the ngien needs. This sensor is designated the Coolant Temperature Sensor (CTS).

Your engine type is some variant of the basic code TU3, possibly a TU3M variant.
On this engine you have the CTS located at end of cylinder head - straight above the clutch bellhousing (flywheel housing). The sensor has a blue plastic connector, hence its often referred to as the blue sensor.
Its important to know that its a 2pole sensor. I.e. if any other sensor found in that area only has got a single spade/cable connector - its not the CTS you have found.
EDIT : the sensor may be green on later models.

This sensor is a common fault on TU3 engines. A failing sensor badly affects coldstart behaviour and idle running.

There is another possibility.
Its wellknown that when you throttle the engine you need to advance the ignition timing - exactly to avoid the bad hesitation on power take up. This is done by a vacuum sensor - designated as the Manifold Absolute Pressure (MAP) sensor. Often this is a small electric device located away from the engine - on a nearby crossmember piece etc. Its then connected via a small diameter rubber hose to the engine intake manifold - or the throttle body.
Both the rubber hose - and the elcectric cable/connector can be at fault. Commonly its the rubber hose that has split over the stud - telling that the rubber has reached the end of its life. Replace with a standard rubber fuel hose in suitable diameter.
The MAP sensor can of course be at fault itself, but not that common.

A third possibility is the charcoal canister purge valve. This looks similar to the MAP sensor - and is also lacated away from the engine - with a connecting small dia rubber hose. Check this rubber hose - or try block it.
This purge valve is only opened while engine is at normal temperature and running under load - to vent the charcoal from petrol fumes. Its in no way an important function for the engine running.

Post by **philhoward** » 15 Feb 2007, 21:18

Thanks for the extended explanation...i'm not too knowledgable on the TU engines! XU's are more my thing - moreso general EFi systems

pug_owner2002 · Post by **pug_owner2002** » 15 Feb 2007, 21:45

Thanks both for the replys!
I will check these out tommorow afternoon and report back.
I did see black circular "thing" with a rubber hose that seems to be connected to the breather/vacuum pipes and some wiring going to it near the drivers side (on a right hand drive car) wing, which i belive from what you have said to be the MAP sensor.
If the temp sensor was at fault would the engine management light come on or not? as there are no warning lamps illuminated when driving.

Thanks again for all of the helpful replys.

AndersDK · Post by **AndersDK** » 15 Feb 2007, 22:53

A failing CTS will set the engine fault lamp - and store a fault code in the ECU. But then again the fault lamp (bulb) may be at fault

Note that the MAP sensor will have only 1 rubber hose connected. The purge valve will have 2 hoses, as it is an electric valve inserted to block the pipe line.

pug_owner2002 · Post by **pug_owner2002** » 16 Feb 2007, 10:02

I can assume that the CTS is not at fault as the fault lamp illuminates when the ignition is first turned on and then goes out when the engine is running.
I will check the other items this afternoon if the weather is ok and report back.

Thanks again.

pug_owner2002 · Post by **pug_owner2002** » 24 Feb 2007, 12:14

Hello All,

I've had a look this morning and the rubber hose appears to be ok.
The picture below shows what I think is the MAP sensor, hopefully someone can tell me if I am correct.
One test I have tried doing is disconnecting the rubber hose from what I think is the map sensor (the hose I disconnected is on the right of the picture) this seemed to make the car run better and never made the fault lamp come on?
Is the pipe that is on the left of the picture the one that goes to the charcoal canister? if so do I just split it and block it up with a bolt or something?
Thanks again for any help as it is much apprecited.