Suzuki 4WD Club of Victoria

Up to date hadn't spent any serious time looking at Sqeezel performance add ons - but had the opportunity to investigate the cheapest DPChip add on unit.

This is for a common rail system and intercepts the rail pressure transducers signal which is essentially 0 - 5 VDC, with an offset top and bottom to allow short to ground and supply detection.

In unmodified operation the rail pressure transducer is monitored by the ecu to correct for variations in rail pressure.
What the DPChip does is intercept this signal and fool the factory ecu into believing that rail pressure is lower than it really is.
This causes the factory ecu to boost the fuel pressure thus adding more fuel and affecting the engines power output.
Interestingly there are no other input signals to the unit so RPM, temperature etc etc have no effect.

The unit has a multiway switch that controls the level of modification to the sensors signal.
The original signal is a straight line, all the dips are caused by the DPChip. The greater the dip the lower the ECU thinks the rails pressure is and therefore the greater the pressure increase over standard. Note that this is only applied towards the top end of the systems operating range. There are limits however to the modification that can be applied - they are very carefull not to allow the rail pressure to get above the rated maximum and risk splitting the rail or associated pipework.

The hardware itself should cost nothing - anyone even slightly competent with microprocessors system could build and program one in a day - they are that simple electronically.

There are much more complex diesel interceptors out there of course, with much greater costs. Needless to say the OEM's are very aware of the interception technologies that are in use to resolve suspicious claims ( why do you think we play ??? )...

Still someone is making LOTS of profit out of the simple systems.

So what your saying is you can make a chip for my Jeep inexpensively Ross?

Your assuming I'm "moderately competent"....... and haven't got a "few" other things to work on.

The Jeep would have to be a common rail system with the same pressure transducer system for this interceptor to work.
Also you would need to spend some time getting the curves set to suit the engine.

Playing with other peoples engines is an activity fraught with risks.......

Still the hardware and software is straightforward once you know how it operates.

And in any case Bill, I think you'd want to be monitoring EGT and have no other obvious restrictions in intercooling, exhaust and inlet before you tipped more fuel in.

Steve.