Hyundai H100 Van - ?Engine Management? Problem.

[squidgelet10]

Greetings each.
I just bought the van featured in the link below.
http://www.ebay.co.uk...sid=p3984.m1423.l2649

I am puzzled by a fault which appears at around 20 miles from a start of a journey, otherwise the vehicle is fine and I am very pleased.
At around 20 miles the ?engine management system? appears to go into "limp mode" (with no display to corroborate this though). When in this state the throttle becomes totally unresponsive and refuses to increase further than 2500rpm.
If the engine is stopped and is then re-started again all is fine, until the next time, ad infinitum/ad nauseum.
Any ideas regarding the possible cause of the problem please?
Be good!
Cheers.

[TWR]

Squid, I have been driving a Renault Kwango that is doing the same thing, as you say, turn off key even in motion & the van is OK, ( & before anyone Say's it, do not turn the key fully to the off position, Its been diagnosed Management system fault, I have inserted WD40 into the Connecting plug & it seem fine for a while then starts again, get a test done.