How to reduce fuel from Injection Pump for a 2002 VW TDI

Josh8Loop · Post by **Josh8Loop** » Mon Aug 24, 2009 6:24 pm

Hey Guys,

I was wondering if there is an easy way to defuel the engine by a certain percentage perhaps through the IP actuator electronics? I know the Evry mod adds more fuel by dampening the signal from the IP, would amplifying it a bit do the reverse? Or perhaps should I fool the MAF sensor into thinking it is seeing less air coming in than it actually is?

The goal is to reduce the fuel qty sent to the engine by the IP, and substitute fuel vapors into the intake after the turbo,MAF,MAP,IAT sensors. Goal is better MPG by providing a percentage of volatilized fuel vapors into the intake in lieu of liquid diesel from the injectors. The fuel vapors used would have a high enough auto ignition temperature to only ignite in the cylinder after the injector squirts in fuel.

CoolAirVw · Post by **CoolAirVw** » Thu Sep 03, 2009 10:47 pm

Are you making a hydrogen generator?

NOTE: No need to "de-fuel" inorder to "add-fuel". The increase in power from the "add-fuel" would automatically result in you backing out of the throttle which would "de-fuel".

Josh8Loop · Post by **Josh8Loop** » Fri Sep 04, 2009 12:08 pm

Hi there,

Thanks for the response! I am not making a hydrogen generator, at least not the HHO type. I am using other methods to produce syngas for the alternative fuel.

I see your point on the adding fuel will reduce the throttle position to maintain a given RPM. I have a feeling in my case that not reducing the fuel from the IP would lead to a rich condition which is what I hope to avoid. I want to mainly use the IP injected diesel to control the start of combustion and use my alternative fuel to compensate for the reduction in the diesel.

I am still contemplating your response, and you may very well be right.(probably

) I wanted the throttle position to remain virtually unchanged while still supplementing my alternative fuel. I am not sure what other functions of the engine are tied to the TPS? EGR,Load calculation, and perhaps others.

Josh8Loop · Post by **Josh8Loop** » Fri Sep 04, 2009 12:12 pm

Coolair VW,

Just noticed your location in St Louis. My wife, kids and I moved from Springfield Missouri a couple years ago so I could go back to college down here. Boy I sure miss that area!! I miss how nice midwesterners are. And also you guys are probably getting some fantastic weather right now(70's) Makes it a pleasure to work outdoors in that weather!!