hello all 

 

car showed simultaneous P0170 and P0301 fault codes this morning.  the engine didn't seem to be misfiring (clutch in and revved ok).  fault cleared using ODBII and switch on/off but comes back.  car runs fine until at 90C.  Engine seems to be in limp home mode, refusing to rev about 2000. 

 

I don't have a compression test kit to hand but I really doubt that it's a compression issue or spark issue. 

 

Any thoughts please? 

 

 

I've swapped two of the coil packs to check whether they are culprits and now have misfires ok both cyl 1 and 2.  So first step is replacing the coil packs for both (I broke the connector housing on cyl2) and the plugs.  No point in trying further diagnosis until those are known to be good.  

 

coil packs and spark plugs replaced on cyls1 and 2.  that seems to have resolved the problem for the time being.

My 2007 1.2 12V used to go into limp mode occasionally under heavy load (eg blasting through roundabouts) until I changed a coil pack which appeared to have been cracked and "repaired" with a soldering iron. Changing the plugs also stopped the uneven idle it always had, to the extent it would often cut out idling in traffic.