Thread: THE PROCESS OF ELIMINATION - ADVICE PLEASE GUYS

Originally Posted by Jazzman

I'd appreciate that. I'll do the same.


Disco W.A mentioned he had a similar fault with a bad earth at the ECU.


http://www.aulro.com/afvb/showthread...08#post2301308

ok so here's the deal so far,

i removed the clutch sensor it did SFA so i put it back on, checked the throttle harness near the potentiometer no oil there so that was a good sign, rehecked the ECU found more oil so cleaned it out again, and postioned the ecu on an angle to help any more oil drain out. pulled the rocker cover gasket changed the injector loom, there was oil in the plugs big time and all through the harness, put a new gasket in, used a little threebond gasket sealant as well (stopped the leaks which was nice) and around the plug itself no leaks so far - torqued it up, changes the inter cooler hoses to nice new silicon jobs and chucked the old elbow hose that was delaminating checked all the other connections and fuses, got under the passenger seat, and lo and behold we have a dual battery setup from the PO thankyou sir! it was crusty and horrible in there though so pulled those out cleaned them up and serviced them etc, one wasnt earthed properly either. checked the wastegate again and dialled it down another full turn (havent hit overboost yet) put it all back together and went for a long run into the hills.

Result? its about 80% better, yesterday it didnt seem super great but on my second run this morning the surging is like 80% better than it was, it will drive in second gear and even idle along and up hills in second gear with no throttle and no jumping about like a bipolar grizzly bear like it used to. i still feel very slight surging at 100km/h when im holding speed... its way less than before it almost feels like im driving on a windy day and the wind is intermittently hitting me front on and slowing me down a tiny bit, but its bugger all now.

my guess is adjusting the wastegate and changing the oil ridden harness were the two biggest factors affecting my engine. I have a new NNN ECU coming from Jose shortly at TD5 inside and the new allisport intercooler as well with a boost box so we'll see what difference that makes. also i'll have the chance to put it onto a nanocom thanks to help from the forum guys in my area so it'll be interesting to see what codes have registered.

** INTERESTING SIDE NOTE**

in the course of doing the fault finding an repairs i got fairly tuned into my engine with what was normal and what wasnt, after adjusting the wastegate and cleaning the harness for the first time i noticed my engine was a bit beserk, id put my foot down and it was like it was already chipped, ironically after cleaning the harness again the second time it seemed to disappear and go back to the original state.... weird.

subsequantly adjusting my wastegate has seen little improvement even using full turns. i still havent hit overboost but havent seen any substantial gains either.

overall im about as happy as i can be till i get my new ecu/boost control and cooler. im guessing that a surging engine seems to be the result of a few related circumstances not just one definitive problem with the car itself, which is why its hard to find concrete answers on the subject. for the other guys having the same problem id suggest attacking it from every angle: harness, wastegate, potentiometer clutch sensor, map etc etc that way you know for sure where you stand.. especially for me as i have only had this car for about 2 months so im still learning whats outta the ordinary and whats "normal defender behaviour"

If you didnt remap it yet better ask for a remap with wide range MAP rather than boost box, IMO that voltage clamp(cos that's what it is) doesnt do any good to your engine cos it only tricks the engine management so the ECU will calculate fueling based on vitiated MAP reading corroborated with real MAF reading(which might top up with greater boost) so the addaptive strategy will be mixed up bad... though if you decide for boost box at least have an EGT gauge fitted to be on the safe side