E53 2003 4.4i Severe Pinging/Detonation under load, reduced power.

[Jusbok]

***UPDATE:
So.....still facing this problem....

Sometimes throws codes and flashing CEL and sometimes not, but ALWAYS has the same lack of power and pings (VERY BADLY) under acceleration - as if the car is in limp mode but with the added pinging (detonation)

Only the three same codes, ever thrown (see initial post below).

Done new fuel pump and filter, theres no blocked exhaust, checked every vacuum hose for cracks etc - nothing.

ANY ideas ANYONE.

Dealer/mechanic/nobody can give me an idea of what it could be.

DIY opinions!?


*************************** ^^^^


Hey Guys,

Been a longtime reader of this forums for the past 3 years, ever since I had my X5 - havent even needed to post to ask you a question, database searches prove wonderful.

Anyways, time to ask for some help...

Finally the X5 has stumped me, everything else (ALOT) that has gone wrong to date has been rectified, with the help of these awesome forums.

I will start with what the car is doing.

The Mrs reported lack of power one day and engine light flickering on and off. Immediately I took it for a drive and it under acceleration/load it would PING severely and have retarded power all through the rev range.

So what I have done:

Codes its throwing are as follows:
"P1341 - Multiple cylinder misfire with fuel cut off"
"P1343 - Misfire Cylinder 1 with fuel cut off"
"P1325 - Misfire cylinder 2 with fuel cut off"

I have, changed all coilpacks, timing chain tensioner, fuel filter, oil, sparkplugs.

It is unchanged however the cylinders seem to change with the misfire codes, after I erase it could be another cylinder misfire....

I have searched for these symptoms everywhere and everyone seems to get different symptoms to mine specifically - the car seems to idle fine, only happens under load/accelerations. The pinging is severe, there is NO SMOKE (white blue or any kind) coming from exhaust.

Another question/symptom, it seems I am only getting emissions from the left exhaust, the right seems to be blocked at idle with only limited pressure exiting the exhaust??? Is a blocked cat possible?

ANY opinions would be a godsend...

Thanks all

Justin

Perth Australia