TD5 Power Box Tuning Problem

[Aloysius]

I have just installed a DieselTorque power box made by Vector Tuning in Germany. My car is a Defender TD5 CSW 1999 model. The power gain is very good with no smoke. It pulls much better on the open road.
The problem is that the engine dies sometimes. It is as if the injectors are switched off one by one untill the car stalls.
I switch off and restart then it runs well again for sometimes a day or two. It seems to happen only in town at low to mid revs. It has never happend on the open road. The engine does not over boost (I have a boost guage fitted). The manufacturer has suggested moving the jumper to a lower setting but that did not help. I had the box exchanged by DieselTorque but that did not help either.
Without the box the engine has never cut out while driving. And no, there is no oil in the wiring harnass or on the ECU plug!
The Box seems to work in other Defender TD5 vehicles.
Where can I start looking for the fault?

[Blknight.aus]

where have you placed the box? it may be picking up random interferance from some outside source or overheating.

[Bundalene]

Hi, I know you say there is no oil in the plugs. I had an identical problem with my 99TD5 Disco, started fine then at mid rev range or under a bit of load it developed a miss (just like one cylinder not working) which stayed until I turned the engine off. It started OK but most times the problem resurfaced. In my case it was oil in the injector loom. New loom from Karcraft - no more problem. Perhaps you have a problem with the injector loom regardless of oil problems. Cheers, Erich.

[Aloysius]

Thanx!! Am going to replace tappet cover gasket tomorrow due to small seep at rear of engine. Will check injector loom again. Properly! Also will check for damage to loom. I went as far as opening the ECU to check for oil. There is also no sign of oil at the engine side. Could be some other problem with the wiring like you suggest. Or the tuning box is crap and confuses the ECU???? But why do they work in other TD5 vehicles? The box lies next to the ECU by the fuse box. The box does not seem to get warm at all.

[Aloysius]

Had the Landy checked on Autologic at Taurus4x4 and the airflow meter was found open circuit. All the injectors also had open circuit errors. The injector codes are correct. I replaced the injector loom and the airflow meter (RRRRR!!). The error codes were reset. Now I have to put the DieselTorque box back in and see what happens.