Spaniard Antonio Garcia made a stunning start from fourth thanks to the rear-wheel drive of his BMW 320i, but Terting was able to pull away. The German then appeared to struggle with his front tyres, but still held off Garcia to take the win by +0.693s.
Terting said: "It was an unbelievable feeling. My team did perfect work. At the beginning my car was good, but on the last five laps I was getting understeer because my tyres were wearing down."
Roberto Colciago was stunning in his independent Honda Accord to finish third. The Italian, who had been fastest in qualifying, started in 20th after retiring from race one.
He climbed his way through the field, and made mincemeat of works Alfa Romeo driver James Thompson, who was suffering from massive understeer after damaging his splitter in a trip across the grass. Colciago had a mesmerising last lap battle with race-one winner Fabrizio Giovanrdi trading paint with the Italian throughout the lap.
The battle ended when Colciago got though a few corners from home after nudging Giovanardi wide. Giovanardi tried to fight back, but still finished 0.117 seconds behind on the line.
Stewards will no doubt look at the battle carefully after the race to decide if either should be awarded a penalty for this or the next race.
Colciago said: "We had a good car and great race setup. Fabrizio didn't want to let me past I don't know why because he was fighting for the Championship and I really wanted to get on the podium."
Thompson finished fifth, ahead of SEAT driver Tom Coronel.
BMW driver Alex Zanardi made a rocket start, but on the opening lap he collided with countryman Gabriele Tarquini. Zanardi got going again only to get back into the pits and retire, and Tarquini's had too much damage on the front of his car after hitting the wall to keep going.
Rob Huff was running strongly however spun out of sixth onto the grass at half distance. Because the turf was newly laid, the Chevrolet driver found himself beached.
SEAT Jordi Gene was the other retirement. After a broken driveshaft ruined his first race, the Spaniard steering failed five laps from home, and he couldn't avoid driving into the tyre wall.
Pos Driver Team Time
1. Peter Terting SEAT Sport 26:10.825
2. Antonio Garcia BMW Italy-Spain + 0.693
3. Roberto Colciago JAS Motorsport + 7.461
4. Fabrizio Giovanardi Alfa Romeo Racing + 7.578
5. James Thompson Alfa Romeo Racing + 11.621
6. Tom Coronel GR Asia + 13.038
7. Rickard Rydell SEAT Sport + 13.630
8. Nicola Larini Chevrolet + 17.091
9. Andy Priaulx BMW UK + 17.543
10. Giuseppe Ciro Proteam Motorsport + 21.098
11. Augusto Farfus jr. Alfa Romeo Racing + 21.704
12. Stefano D'Aste Proteam Motorsport + 23.079
13. Jason Plato SEAT Sport + 23.822
14. Alain Menu Chevrolet + 25.176
15. Marc Hennerici Wiechers-Sport + 28.942
16. Carl Rosenblad Crawford Racing + 29.373
17. Dirk Muller BMW Deutschland + 30.788
18. Carlos Mastretta GR Asia + 34.149
Driver Team On Lap
Jordi Gene SEAT Sport 12
Robert Huff Chevrolet 7
Alessandro Zanardi BMW Italy-Spain 1
Gabriele Tarquini Alfa Romeo Racing 0
Fastest Lap: Fabrizio Giovanardi, 1:30.867 on lap 4
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