Xsara Picasso 1.6i sluggish and juddery

[JamesQB]

Hi everyone,

I've recently bought a Xsara Piccaso 1.6i. It's a 2002 model, petrol, manual and according to the Cit service website, should have 100 horses galloping beneath the bonnet.

It feels more like 60 lame horses though. Overtaking is something other people do now. Not me.

Sometimes when accelerating it feels juddery from the engine.

I have a Lexia but haven't managed to get the software to install on my new Windows 7 installation. Reading codes a couple of months ago when the car still belonged to my neighbour didn't show any faults.

I'm much more familiar with diesels and have forgotten a lot about petrols.

I understand the coil pack is one possibility; any way to be sure before spending money I don't have?

I see this engine has 2 lambda sensors. The last petrol car I owned had 1 lambda sensor and this wasn't used until the engine had warmed up so if the car was poor before the engine was warm, it removed the lambda from the equation. Is this true with a 2 lambda system? Car is equally poor cold and hot.

I also saw a MAP sensor on the intake manifold/throttle body. Is this likely to affect power output? Does the Lexia give a live readout of the MAP sensor?

Any other ideas what might be wrong and how to check, as I can't afford to buy part after part until something fixes the problem.

Thanks!

[Hell Razor5543]

I cannot help with the car, but what bit width is the Windows 7 you are running? If it is 64bit you will need to set up a 32bit Virtual Machine with good USB access, as the Lexia software is so old it has no 64bit capability.

[Mandrake]

Your first port of call should be getting your Lexia running - changing sensors etc by guesswork is just going to cost you a lot of money and get you nowhere as the possible list of faults is huge.

As James says it only works on 32 bit versions of Windows - whether XP or Vista or 7. I personally run it on Windows 7 32 bit on an old Acer laptop with no problems at all. If your windows is 64 bit (Start->right click Computer->Properties) then you will need to set up a virtual machine, in which case the best choice is to install XP SP3 within the virtual machine as it has the least system requirements.

You're right that oxygen sensors aren't used during initial start, however they come online pretty quickly - within about 2 minutes even for a cold start.

Lack of power and juddering is most likely a misfire but the causes can be numerous hence wanting to get the Lexia working to make a proper diagnosis. Even if a fault code is not being set you can look at the live sensor data to get an idea of how the engine is running, and some of the sensors such as TPS and MAP are easily tested with a working Lexia.

Is there an obvious vibration of the engine at idle like a misfire ? Does it stumble and hesitate if you punch the throttle at idle in neutral ?

[Hell Razor5543]

A short cut to the Device Properties screen is to hold down the left Windows key (to the left of the space bar), and press the Pause key (right key of a group of three keys, near the numeric keypad).

[JamesQB]

After much ado, I have managed to install virtual machine and XP mode, and after even more ado, I obtained Diagbox of the right version for my clone and all is working.

Only the BSI showed fault codes. Cleared them and checked again tonight after couple of days driving:

*Permanent fault: no comms with air con
Permanent fault: +APC open circuit
*Intermittent fault: EOBD or engine ECU
*Intermittent fault: Engine speed

I read elsewhere that the asterisk means that the code is a known phantom fault. From what I could gather, +APC refers to the voltage line when the key is turned to 1st or 2nd position. Couldn't find anything on what the code actually signifies though, when all is working.

So, nothing that helps with the low power and slight judderiness.

The judder is almost absent sometimes, and other times quite noticeable. I've just changed fuel and air filters, and fitted new plugs. No obvious difference.

When idling, other than random times when the idle speed won't stay steady, it seems smooth. Sudden revving in neutral doesn't seem to cause any misfire or judder. It seems to be an issue under load.

Any advice on what to check on Lexia is most welcome. Also, can I record logs while driving with Lexia?

[citronut]

have you checked/cleaned the idle stepper motor, as these cause the idle to fluctuate sometimes quite dramatically,

remove it from the throttle body blast it out with carb cleaner, blow dry with compressed air, then give it a very slight lub with the likes of duck oil or
aerosol 3 in 1

only use a very light oil,

then refit and switch the ignition on and off 2 to 3 times, this resets the stepper motor

[JamesQB]

Forgot about this until now as the judder is worse.

I cleaned the stepper and idle is now smooth.

I changed the lambda sensor by swapping the pre- and post-lambda sensors around and that caused a very noticeable power increase.

The judder remained though and is getting worse. Mostly shows up when accelerating right after going into 2nd gear. Very annoying as it happens as I pull on to the main road (60mph road) where I need to get moving quickly but it judders (little kicks like driving over bumps) and there's less power while it does that.

Lexia shows nothing wrong. Any ideas?

[JamesQB]

I should add that what puzzles me most is that it seems exclusive to 2nd gear right after changing up to it, and lasts a few seconds till I'm revving high. Or it's most noticeable then at least, as can't say I'm really aware of it happening any other time.