chime back with any progress

 

Just catching up on your thread and wanted to make a point that I saw. You thought your voltage issues were due to the mini battery but that wouldn't be the case. The battery is only there for 3 reasons; cold cranking the starter, reserve power if the alternator amperage rating has been exceeded, and to smooth out the charging system noise/ripples caused by the way the alternator creates DC current (the battery does this naturally by default).

Once the engine is running, the battery is not the power source, the alternator is. The battery actually creates a LOAD on the alternator since it adds resistance to the system while being charged. So in essence, the mini-battery is actually relieving the alternator of some it's duties since it requires less current. Any power delivered above 12.6 volts is coming solely from the alternator.

People NEVER think of upgrading their entire electrical system when doing performance mods and it's kinda silly. The best thing you can do is remove the factory grounds anywhere that connect to the chassis and look at the painted surface and threads in the bolt hole. The only source for current to pass is through the threads where they happen to strip away the paint as the bolt is threaded into the hole. So take some sandpaper and sand away the surface where the ground terminal rests on the chassis and bolt it back up. Spray the connection with matching paint or clear coat spray (even clear nail polish will work) so it doesn't corrode. This alone will help your entire electrical system perform far better, even with the factory wiring.

I suggest the ground cable from the engine block to the chassis, from the battery terminal to the chassis, the ecu to the chassis and the fuel pump to the chassis. Those Alone will help tremendously. Some of you super high rpm guys may notice voltage dropping at high rev's when logging. That is usually due to the alternator spinning faster than the brushes were intended to operate at and can cause funky stuff to occur as voltage drops. Find a machine shop that can take make you a slightly oversized pulley for your alternator and it can definitely help out. Voltage at idle may drop a bit but it's easier to live with tuning tweaks at idle than chasing ghost at redline where damage can be severe.

I apologize for the off topic post but I thought it was worth sharing. People can chase electrical issues the wrong way sometimes and waste time troubleshooting the wrong stuff.

 

JOT....Thanks for the info. I already have a grounding kit and all engine grounds have been cleaned as you stated. I am well aware of electrical gremlins as I used to be an Apache Helicopter electrician. Grounds are very important. The claim about the fuel pump and ecu grounds.....GOOD IDEAS.

My statement about the mini battery comes as a result of noticing that voltage seems to remain more stable with a larger battery. The reason is obvious.

 

In fact I've been curious if a hotter NGK copper plug than the BPR7ES might even work better with E85. Has anyone ever tried BPR6ES plugs in their EVO? I believe that is the OEM plug for turbo DSMs. There is also a BPR5ES, and BPR4ES, and BPR3ES, and BPR2ES.

 

It may work with the E85 but I know they cause issues with pre-ignition on pump gas because I had a customer with all sorts of problems and found out he ordered the 6's by mistake. Thing even pre-ignited at idle.

 

I have the plugs sitting on my bench gapped and ready to go in. Family stuff has been the priority lately.

 

Just remember to post back when you do. Reread my post #36 - I'll bet that clears things, but take those steps if it doesn't.

 

Replaced the plugs.....Still have both problems
Modded the fuel pump.....still have both problems

Played with the tune.....still have both problems

Here is an odd finding though. I turned my AVC-R settings all down to 20 duty cycle as an attempt to see if boost would come down to reduce the cut out problem. NO the problem still exists....AND what is really weird is that boost won't go below 21psi (I have an 18psi WGA) so this may just be the case.

AND....even at the lower boost.....AFR won't go below 12.5.

I am really starting to get pissed off.

 

need to get the logically head thinking cap on.
haven't read the thread back for a week so forget the main issues but going on the last post several issues exist! i'd sort out each one individually especially the fundamentals like boost control.
i.e boost not doing what you expect altho perhaps not to do with the initial running issue needs sorting so it is functioning correctly
hope ya find the prob soon

 

Is it only lean up top or everywhere at WOT? Try dropping the entire fuel map to the lowest value from 140 load and up and see if it's getting richer during spoolup and stuff. If not, you may have a corrupt rom.

I would start thinking about your FPR and check the vacuum line going to it. It may have a small leak somewhere.

 

It is lean everywhere at WOT.....AND.... at around 3000 rpm the car feels like it hits a brick wall....cuts out HARD and goes rich. After a couple hard hits....it goes into pulling like normal....albeit lean.

 

Have you logged AFRMap to see if it appears to match the appropriate cell values? IDK if anyone sells an adapter to install inline to check your fuel pressure while under a load. I use an old one that Pruven Performance used to sell. Why Mitsu decided against a fuel pressure testing port on the evo's is beyond me.

 

I have an AMS fuel rail. It has a port for a fuel pressure source. I may give that a shot. At this point I am aiming towards a corrupt ECU.

 

Boost levels are generally LESS than your WGA rating since there is a pressure drop thru the Intercooler and piping. So something is probably restricting flow to the WGA. Does the EBC and FPR vacuum line share the same source by any chance?

 

The EBC pressure sensor, my boost gauge and MAP sensor all share the same pressure/vac source off of the intake manifold from the line going from the intake mani to the FPR. The EBC solenoid has a direct line from the turbo outlet nozzle as a pressure source and another direct line from the solenoid to the WGA. The BOV has a direct source from the intake manifold.

All lines were vacuum and pressure tested and OK. They are all zip tied too.


Thanks for your constant assistance. This is really bugging the heck out of me.