306oc - Peugeot 306 Owners Club & Forum

Right I've had this fault intermittently for a little while now but it's just getting worse and worse.

A few weeks back my EML came on. I plugged in Peugeot planet and got a fault ' mixture regulation fault - upper stop'. Cleared the fault and it stayed a way for a while then came back and went a few times. During this time, there was no noticeable difference in power or running except for stalling occasionally when dropping to idle (my icv is mega f*cked)

Today it came on and stayed on but today I noticed a difference. It felt very sluggish. I pulled away from the lights and out it into second at 1500rpm and planted my foot. It climbed through the revs until I hit about 3500 and then it took off. It was like boost but really quite violent!
Light has gone out again but this still remains. I've done it several times now and same thing. Hits 3.5-4k and it takes off like a rocket!

My thinking was either MAP sensor (sticking st a certain value) or lambda sensor (I'm 99% sure my cat isn't working properly but I've had faulty lambadas before and they havent done this!). Lambda is only about 6 months old.

Just after some more input on this before I go spending or just scrap the bastard.





(it was good fun when it hit 3.5k though )

Not sure if the lambda is the same between our cars, but when do do my decat this weekend you're welcome to take the lambda off mine and give it a go?

Also the car might be feeling different now as it's timed right...not by a huge margin, mind, but something to consider.

Scott Wrote:Not sure if the lambda is the same between our cars, but when do do my decat this weekend you're welcome to take the lambda off mine and give it a go?

Also the car might be feeling different now as it's timed right...not by a huge margin, mind, but something to consider.

Cheers Scott but I'm positive the lambda is working ok. The readings from it are fine and as said, it's only 6 months.

This sudden surge in power can't be because of the rebuild. It was nice and smooth delivery until the light cam back on and now it is really violent! It's like Im coasting and suddenly slam my foot to the floor.

Does your speedo work?

exactly the same problem ive been having! Check the MAP!

Yep fine. Why?

Problem I had with my gti6 when the speedo sensor was broken/unplugged, no power at all til about 2k and then liked into life as if it was bumpstarted.

You can rule out lambda, that usually causes hesitation at part throttle and acts normally at full throttle, lambda values are ignored by the ecu at wide open throttle.

Could be throttle position sensor or map sensor. I've had issues with the tps before and that gave weird jolty power but never had any map sensor problems so can't comment.

cwspellowe Wrote:Problem I had with my gti6 when the speedo sensor was broken/unplugged, no power at all til about 2k and then liked into life as if it was bumpstarted.

You can rule out lambda, that usually causes hesitation at part throttle and acts normally at full throttle, lambda values are ignored by the ecu at wide open throttle.

Could be throttle position sensor or map sensor. I've had issues with the tps before and that gave weird jolty power but never had any map sensor problems so can't comment.

Cheers!

Can't see it being the tps as iirc, the ECU takes the map values over the tps value but once again I do have a spare so can check if needs be.

if the idle control valve is acting eratically i found this to be due to a faulty MAP :/

Mixture upper stop sounds to me like the request amount is higher than the map has values for... I.e. you're pulling in too much air...

Will PP tell you lambda values at WOT even if the ECU is in closed loop?

Ruan Wrote:Mixture upper stop sounds to me like the request amount is higher than the map has values for... I.e. you're pulling in too much air...

Will PP tell you lambda values at WOT even if the ECU is in closed loop?

Yes it does. I'm off to kris Bs now do will have a play with pp there while he works his magic!

Right I fitted a new fpr and map today and normal driving conditions are back as they were but there is still a fair bit of hesitation under full load. Now the fact it's filling the cylinders with oil can't help but any other ideas?

air filter/ injectors need a clean? Also, if you need an extra set of eyes for pp give us a shout

Thanks for the offer Sam

Right fitted a new FPR and MAP yesterday and it's not made a blind bit of difference. Still suffering my 'boost' problem.
Went out for a drive with the laptop plugged in and when you let off the throttle, the lambda was dropping to 0v (should normally float between 0.8v and 0.3v normally. Weird thing was it wasn't going out of range under hard or normal driving.
It wouldn't surprise me if the stupid amount of oil running through the exhaust has ruined the lambda but it's weird that it only dies on overrun?

Niall Wrote:Went out for a drive with the laptop plugged in

I hope you used one of these:

Nope used this

£10 clearance rack... Classy as always Grant.

I dont get it, you used a pink suit to work a laptop? lol


Surely you would have been able to see it yoruself if you weren't busy pulling stupid faces such as this...

Pulling faces? What you on about I'm not pulling any faces......

Right more findings

It only does it when it's warm (rag it from cold (don't make a habit of this) and its fine)
EML seems to come on after about 2 or 3 minutes of driving from cold and as soon as it does, if I slow down and dip the clutch, it stalls even on cold idle

Any ideas

Oh and now it's started misfiring horrendously. Someone help!

You need to show it whose boss. Set fire to it, it'll sure learn its lesson!

Scott Wrote:You need to show it whose boss. Set fire to it, it'll sure learn its lesson!

I am getting so so close to scrapping it you wouldn't believe.

Going to get rid and buy a golf. There much more reliable

Good one!

Is it just that everything inside the engine is getting covered in oil and also the sensors are getting covered so aren't working properly? Gutted for you to be honest mate, it's a shame you can't just get yourself another engine and drop it in

Scott Wrote: Good one!

Is it just that everything inside the engine is getting covered in oil and also the sensors are getting covered so aren't working properly? Gutted for you to be honest mate, it's a shame you can't just get yourself another engine and drop it in

I think/hope it's just that the lambda has packed up cos of the oil. Only other thing I can think of is the ECU has gone bad

Not going to repair it until the bottom end is done this weekend but it's just depressing me that it's getting worse and worse by the day!

Don't suppose you've asked your local peugeot master-tech about it..? Unlikely they'll be able to help, but worth a go.

Poodle Wrote:Don't suppose you've asked your local peugeot master-tech about it..? Unlikely they'll be able to help, but worth a go.

My local Peugeot are wankers. So doubtful! Haha

I was doing some reading about yesterday eve and it looks like it could be the ECU. Found a company that does a refurbished replacement marelli (instead of Sagem so doesn't suffer from the spiking issue) ECU with lifetime warranty for 195 quid so once the bottom end is rebuilt, I might order one.

I wouldn't waste any time getting a replacement ECU mate, it's money you could put towards basic aftermarket management.

The trouble is, that with the GTi6 inlet and exhaust manifolds and other changes the sensors are reading outside various parameters that they normally would, so chances are a new ECU would just have a 'temporary' lifespan on that engine, before confusing itself. Part of the reason I returned my Cabriolet back to standard manifolds (although in hindsight, I wouldn't have bothered putting the exhaust back to standard as this doesn't seem to affect the car at all). The new TB from a GTi6 has to be maybe 50% bigger than the standard one, so your letting in a whole lot more air. Not to mention that the ambient air mass inside a GTi6 inlet manifold far outweighs what should be in there, with the crappy restrictive plastic one...

In your position, again, I would source an aftermarket ECU (can you get a megasquirt one?) and GTi6 cyilnder head. Get it mapped and have done with it.

c.a.r. Wrote:I wouldn't waste any time getting a replacement ECU mate, it's money you could put towards basic aftermarket management.

The trouble is, that with the GTi6 inlet and exhaust manifolds and other changes the sensors are reading outside various parameters that they normally would, so chances are a new ECU would just have a 'temporary' lifespan on that engine, before confusing itself. Part of the reason I returned my Cabriolet back to standard manifolds (although in hindsight, I wouldn't have bothered putting the exhaust back to standard as this doesn't seem to affect the car at all). The new TB from a GTi6 has to be maybe 50% bigger than the standard one, so your letting in a whole lot more air. Not to mention that the ambient air mass inside a GTi6 inlet manifold far outweighs what should be in there, with the crappy restrictive plastic one...

In your position, again, I would source an aftermarket ECU (can you get a megasquirt one?) and GTi6 cyilnder head. Get it mapped and have done with it.

Yep but that requires lots of money which is something I just don't have at the moment.
I'm going to try a new lambda I have laying around and if that doesn't cure it, it has to be the ECU. It can't be anything else. Ecus on these are known for doing this.
Might swap back to the 1.8 manifold anyway soon but we will see

Oh and I'm not fitting a gti head. I've just fitted a newly refurbished one!

For the first time ever, I agree with C.A.R.

You're best off getting some decent management. If I were you, just save up for decent management, Megasquirt really isn't that expensive.