I recently purchased a used 2001 ford 7.3 diesel. It has been a nightmare. First a new ckank position sensor and cleanning of the injectors. Broke down again. This time wiring at the valve covers. Both sides bad. Broke down again. This time three injectors bad. Dealer says 1800.00. To fix. Seems to me the injector problems are maybe related to the dealers work. Any ideas