As cost-conscious DIY troubleshooters, forum members talk a lot about testing ignition spark. Fuel injector issues and injector misfire codes are also common. For spark, there are surface probes like the Waekon 76562 COP ignition tester that we've discussed. Waekon makes a similar 76462 fuel injector surface probe tester: http://www.amazon.com/gp/product/B0021V0FRE?redirect=true&ref_=pe_58340_166621340_em_1p_1_ti. I have both tools, and they are quick and handy for off-road troubleshooting in the backwoods. Whether you travel with a 4x4 group or alone, carrying these two tools in yo