click here to see original thread

perhaps this repost in this section will recieve more attention.

 

could use some help. thank you.

 

I see one potential problem right off the bat:

In my situation, doing that created a drop in rail pressure as a result of fuel being pushed back through the unused pump.

You really need to conduct some thorough logging via EVOScan and take this issue to the ECUFLash tuning forum.

 

ahh. thanks. i have a hobbs switch and we can hook that up and get the pumps working correctly, hopefully thatll do it. weve been doing lots of logging and trying to adjust things etc etc. and are baffled. lol we thought it could be something as simple as that.

but you never know, well see. i will let you know what happens.

thank you friend

 

First of all +1 to moving to the ecuflash forum. Mods can you please move this thread to ecuflash?

I did several logs of this car during the issues. Basically evoscan reads zero pulse-width on the injectors whenever the issue occurs. Its like a momentary fuel cut. (I would post the log, but I have no way to get it off my tuning computer at the moment due to the only USB port breaking... ) Currently the car is running waste gate boost. So we are not running out of duty cycle even with a single pump.

It is my understanding that regardless of injector size and fuel pressure the computer will still generate a pulse-width, and would only log zero pulse-width if the computer is turning the injectors of for deccel compensation, or fuel cut of some sort.

I did notice when I looked at the throttle% in evo scan, there was dramatic decrease in throttle position at the same time as the data showed zero pulse-width, but my foot remained constant during the pull. Im guessing the TPS is failing and when the computer is seeing a fake decrease and throttle position is it cutting the fuel for deccel compensation.....

That is my current thinking with the problem, Im open to any other ideas, and if I can get the data off my computer Ill post it up.. or take more data with another computer....... Thanks for the help.

 

What is the boost limit set to?

 

lol yay thanks denver for explaining!

makes me realize how much of a noob i am

 

Understood, but as I indicated earlier, you will not get the expected pressure from even a single pump with the present arrangement (two pumps but only one running). Be advised.


And that would be a very strong possibility if the TPS is behaving as you say, as there is a decel fuel cut. The TPS is suspect and needs to be replaced.

 

Taking a stab from a similar problem, different car.

The STI has a plastic disc that sits over a bolt on the floor beneath the gas pedal, and if you pull it off, the pedal travel is too much. So at WOT it see's excessive TPS and shuts off fuel to the car. However, it doesn't show a TPS of greater than 100% in the log because the sensor can't report that much.

Now since I think all evo's are DBC not DBW, but I'm not sure there, I don't see how it's possible, but my bet is something is out of range, something mechanical. And it's telling the ECU to shut off.

/brox