KAOLALI85mm GPS Speedometer 0-160MPH with Tachometer Gauge 0-8000RPM for Car Boat Motorcycle Marine Truck Speed Meter

The gauge doesn't stay on it flickers on and off, I double and triple checked my wiring because I thought it was a short in my wiring but have further determined that it’s the gauge, it also is always finding gps signal , I have place the receiver in clear view of the sky and when it does find gps signal it is very inaccurate on the speed you are going plus the rpm gauge just kinda reads what ever it wants, sometimes it’s correct with the engine rpm’s and sometimes it says it’s at 6-8000 rpm when the truck is at idle , utter junk

I had to fight to get this working because I did not understand the signal requirements. First of all the signal needs to be a minimum of 5 volts peak to peak. The signal also seems to need to be a minimum of 4 pulses per revolution of the engine (theoretically its one, but I couldn't get it to work). The ratio number to calibrate the tach is simply the number of pulses per one revolution. Once I got the tach working it performs great! But buyer beware there is no support out there - you are on your own. My application was a Diesel engine and I had planned on using the cam drive and a hall effect pickup - however the frequency of this was to low to get the tach to read anything. I ended up using the "W" terminal on the alternator and setting the RPM ratio to match the engine speed measured with portable photo tach.

This tachometer is very nice to look at and the motion of the needle upon power-up looks high quality, but it's a piece of junk. The product doesn't work, there are only 4 colors, not 7. The directions appear to have been written by a second grader and no matter what setting is tried, the tachometer will not function; either the needle doesn't move at all, or it points to one spot and stays there regardless of engine RPM. Very disappointed. Such a nice-looking product, too bad it doesn't work.

Don't waste your money. They don't work. This was the second one I ordered, the 1st was from ebay, and neither one worked. If you will look closely at the ones on Amazon, you will see that most of them are by the same manufacturer in China. Spend a few bucks more and get a name brand that works.

Looks clean but doesnt work properly. Very inaccurate and inconsistent readings no matter what settings you use. Instructions are useless and the settings dont make any sense whatsoever.

Junk don’t work sticks at 20 and goes way past 8 cheap junk don’t buy