Blue Chip FMS problem-boost at idle

[NPloysa]

Hi guys. I bought a Blue Chip Fuel Management System with the built-in digital guages, used from a guy on the DTR and from when I installed it 5 months ago, until yesterday it had been performing flawlessly.



Yesterday was a normal morning, turn ignition on, wait for box to show startup menu, pump volts test, then wait for the grid to cycle and start her up. It said it lost my parameters for the box and went to a 15% fueling default (it was set at the full 63%), plus my other custom stuff, RPM and EGT (in "ones" of resolution) on top, boost on bottom (in "tenths" of resolution) and my fueling rate on the bottom also. Everything was reset.



I set the box back up to my defuel temp, etc, etc, etc, full fuel, turned the fuel back on and everything was normal until I looked at the boost.



At idle it was reading 0-. 4, jumping back and forth, (where before it ALWAYS read 0 at idle) and it seemed like boost was building at a much lower rpm (and faster) and acceleration than it used to. At idle my fueling would say 1% then jump back to 0%.



I'm confused! I called Chip and left a message. Can anyone give me any tips until I can call him on Monday?



Nick



P. S. -I did unplug my MAP sensor and it wasn't dirty at all, didn't change anything. Also, I found a cool setup menu. If you hold down all three buttons before you turn the key and keep holding while you only put the key into run (engine off), it will jump to actual EGT temps and then where you would scroll through the menu there is a model year, solenoid parameters, pump volts test, upgrade menu, etc, all in there. Check it out (you guys that have em)

 

[Amianthus]

Be careful in that menu. You can really mess things up in a hurry if you start changing parameters on it. I know about the resetting issue. Well, it's happened to me anyway. I don't know what causes it per se, but Chip has told me that because the FMS is so fickle with it's power supply requirements, that any spikes in the system can cause it to act that way. My best advice to you is to tap into the same ground that the VP uses. This will help limit your spiking issues. See if that helps with your erroneous boost indication also. If not, your board might be toasted, and will need replacement. Please feel free to give me a call if you really run into a snag. I'll do what I can to help. The FMS is a beautiful thing, but MAN can it also be a PITA! Don't lose faith.

 

[NPloysa]

Thanks! I left the solenoid parameters where they were. I will try grounding it into the VP ground again and get a better ground and see if it helps, thanks!



Nick

 

[NPloysa]

I hate electronics!



My stupid box is still giving me problems, ok maybe not the box but my wiring. I called Chip and spoke with him and told me it's probably the ground so I tried that first. He said if the ground is bad it will ground out through the MAP sensor and will increase the MAP voltage to do so, therefore showing a weird boost number.



Tonight I worked on it for 3 hours trying to get a good ground. I tried fiddling with the original scotchlock and the boost problem seemed to go away, but knowing it would come back I decided to solder it. I should have left it alone!



Soldering in that tight of a space is a PITA, let alone trying to make it a good connection. I soldered it 3 different times and nothing. I tried 2 more scotchlocks and still no go. I will work on it again tomorrow.

 

[NPloysa]

I have an idea! Where does the VP ground to? I know its the black with brown tracer wire that comes out of the pump, but where does that actually ground to?



Maybe the ground wire is not grounded properly, just enough to throw the voltage off for the box, but still grounded enough for the VP to not notice.

 

[Amianthus]

It grounds inside the ECM. I don't have a schematic for the ECM, but I can only guess that the ground for the ECM has some special componenets in it that help it perform better (i. e insulate voltage spikes due to bad grounding).



I did get you rmessage, sorry I didn't call back. I was out on a job site and didn't get time until much later at night. I agree that soldering in there is a righteous PITA. I can only suggest s pump cover to guarantee the pump connection that you're trying to make.



The only other thing I can think of, is that you may actually have a MAP sensor that is going bad. The only way I would be able to check it is to connect an OBD reader with data logging to it and see how it behaves.



Kepp working on the soldering. If I can think of anything else, I'll let you know.

 

[NPloysa]

Thanks, I will continue trying to solder but will go look on the classifieds for a pump cover. Anyone have one they don't need? I should have listened to Chip when I called him when I installed the box. He said I would be best off with a cover! Should have done it!!!!



Thanks for the help!