S204 350cdi Limp mode, maybe??

[jcfixerofshiz]

Hi all.
Bought a grown up car a few months back S204 350cdi auto. All been going well and going through all the little things to make sure it'll go on for years to come.
Had the transmission oil and filters changed and plugged into the stars scanner to check for fault code (coolant temp switch over valve. New fitted)
Since then it occasionally goes into limp mode (I assume) won't go above 4th gear, even if I change it to manual. Holds the gears till 3k before changing. No performance.
Engine can be either cold (work commute) or hot after along drive. Doesn't seem to match up to a re-gen cycle either as the idle is still at 600, and stop/start is still working
Turn the engine off and back on, and your good to go till it happens again.
Had it scanned again, nothing.
Anybody come across this one? TIA

 

[AndrewOl]

If you are not getting an engine light it sounds like the transmission is going into limp mode. Cycling the ignition resets it but it will keep happening and it will get worse. Star diagnostic should be able to read the transmission codes to let you know what is going on. If you are not getting any codes then it sounds weird or maybe an issue with who is doing the diagnostic?

 

[jcfixerofshiz]

Yep, weird it is. No light comes on so my thoughts were transmission problem. I'll get in touch with the garage tomorrow.

 

[Larkone]

Don't discount the turbo actuator needing a refurb - similar symptoms. Get it on STAR to read the live values before throwing any cash at it.

 

[jcfixerofshiz]

They had it this week to check the actuator and all seems good.
But today on a 55mile run of motorway and A roads it happened twice, once on acceleration and the other on throttle off cruising, and that one got the engine management light on, so back it goes. That and almost being run off the road by a blind SUV driver causing me to now have a severely buckled Rear N/S wheel (anything above 45mph is terrible). Not a good weekend.

 

[phobos]

hello, I would check if the ammount of gearbox fuild is the correct one, as if it not it can cause issues like the ones that you have mention and also some "kangooring"
Failing that, a STAR diagnostic will be a good way forward here, but I would fo it either way, just to be on the safe side.

 

[jcfixerofshiz]

They have checked the fluid level and said all OK, I can only assume they put the right stuff in. I'll get in on the Stars scanner for a third time to see what it says

 

[suty455]

Are you sure its not doing a DPF clean assuming it has one, mine does this now and again but it does go through all the gears ok just acts very much as if its in sport plus the revs are held much higher at tickover, my Subaru behaves exactly the same when doing a DPF cycle hence am not over concerned, 10 minutes later its fine.
Just to confirm "mine" refers to my E350 not the Subaru

 

[jcfixerofshiz]

Are you sure its not doing a DPF clean assuming it has one, mine does this now and again but it does go through all the gears ok just acts very much as if its in sport plus the revs are held much higher at tickover, my Subaru behaves exactly the same when doing a DPF cycle hence am not over concerned, 10 minutes later its fine.
Just to confirm "mine" refers to my E350 not the Subaru

It's still doing stop/start and idles at 600, not 800 when doing a re-gen. The revs fly up but no power and definitely no gear higher than 4th no matter what setting its in. Wouldn't have thought a re-gen would limit power and gears as a safety issue?

 

[suty455]

It's still doing stop/start and idles at 600, not 800 when doing a re-gen. The revs fly up but no power and definitely no gear higher than 4th no matter what setting its in. Wouldn't have thought a re-gen would limit power and gears as a safety issue?

Well it does for many cars because the EGT is raised artificially, mine idles at 800 on a regen good luck with it