Last week I installed my JDM rear bumper. The install was uneventful. Two days later i drove the car for about 80 miles and noticed a new sound comming from behind my seat. Its my walbro fuel pump whining. I had that installed a month ago and never heard it before. When I got the car home I realized that the part of the wire harness that connects to the side marker was hanging down from behind the rear bumper and the bulb had shattered. I went out that night a drove a bit and the car would not boost past 1 bar. I have a MBC set to 1.5 bar. I have replaced the MBC. I set it and it boosts to 1.5 bar. I get on the express way and it boost to almost 2.0 bar. I adjust it and its fine until i get on the express way. Also, my voltage is now constantly at 14.5 to 14.8 volts. I have a volt gauge and a turbo timer that read the same. Even at idle it sits at 14.# volts. Anyone have a clue. I have since removed the plug to the shattered bulb, replaced 3 mbc's

 

nothing guys?

 

27 views and no ideas... thats awsome

 

****ing monkeys in the engine bay and hiding in the bumper. sorry, good luck though with your problems.

 

thanks man.... i was under the impression that there were some real guru members on this board that could kinda point me in the right direction....

 

the walbro whining is normal . Sometimes it comes and goes and some members experience the whine all the time. What type of MBC are you using/ did it come with a heavier spring ? Have you checked for boost leaks ? I have a 2005 that has 24,000 , i had a massive boost leak coming from the throttle body fixed that and performance was night and day

 

Im using a Helix DNA MBC... it worked fine up until the day the voltage pegged and the fuel pump started doing the whole song and dance. It did not come w/ a new spring... it always worked. Im not sure how to do a boost leak test. Im over boosting at this point whenever i get on the expressway.

 

There are a couple batteries i'm aware of that have slightly high numbers for their charge optima batteries are one that hold around the 14 volt mark. That however is not the problem you describe.

I would look into your voltage regulator on the alternator, alternators are supposed to kick in at the 13.5 volt mark and shut down if they go beyond 14.5 volts. I hope you find your problem soon

 

im using the factory battery... the gauge is pegged at 14 volts and my TT is showing 14.3 to 14.5 even at idle. It usually hangs around 13.6 to 13.8 at idle. Could this be related to the shattered bulb/plug for the reaar side marker?

 

No that doesn't make any sense to me as far as electrical problems go. If anything it could have shorted out but that just means one of your fuses bites the dust.

Now it could be possible, though i find this like shooting a star out of the sky with a pellet gun, that your bulb mishap coninsided with a malfunction of the voltage regulator.

The regulator controls the strength of the magnetic field on the Stator or in lamemans terms the bunch o wires around the outside of the alternator. If say the input voltage of the regulator was damaged... then the current at these cores would be at maximum allowed.

I wish i had a picture to show you of where it is on the car but i dont. Perhaps tommarrow i'll get out my camera and dig out the wire location.

Brief description of how an alternator works:

To explain how a the alternator works lets start easy, first the alternator produces AC current otherwise found in your house. This is converted through a number of diodes, or one way valves of a sort for electricty, into DC or linear (linear like) current.

A normal charging device would imploy permenent magnents, however an alternator uses a simple trick to make its electricity. It uses the batteries power to create a magnetic field. As the other half, the spinning rotator moves past it the resistance by the fields induces current playing off the like wise poles of the battery you basically amplify the voltage availiable up and down as you pass forth. This amplification is what we use to charge the battery, of course its not free energy you have to move the rotator with is of course hard work.

The stator is that "magnetic field" in place of permenent magnets. You could easily trick your regulator by just installing a resister to the input voltage of the regulator.


EDIT:
Sorry for the lengthy post I guess i ramble on

 

Ok... could this explain all the other malfunctions that occured at the same time? Can the voltage regulator be replaced/serviced or do i have to replace the entire alternator?
Im going to check all my fuses and relays tomorrow along with the wire harness under the reaar bumper and see if its damaged/shorting. The car also has only 30,000 miles on it.

 

Dont even worry about the 14 volt idle. That is not a problem, that is actually common.

I dont see a problem at all with what you have posted except for the MBC maybe being set wrong.

Everything else seems just fine.

 

First your questions:
1)The alternator and voltage regulator come as 1 unit so you have to replace them
2)Its unlikely the voltage is an issue after all its maxing out at 14.8 thats a meager 0.3v over normal peak.

Clarity:
Well overvolting any electrical appliance usually gives some pretty odd results, motors like the DC motor in your pump for example would work extra hard and wear out extra fast, sensors may be thrown off due to an "expected difference" in static voltage. Becuase the voltage spike is so low i don't think it should have caused any malfunction on the car.

Testing:
You could test the alternator theory by removing the alternator from your setup. You would have to unhook the charging lead from the alternator and secure the wire so it doesn't short, which would be bad.

Problem:
Unfortunately the alternator isn't an easy place to get to since its located behind the motor near the firewall..


Notes:
I wish you luck on your journey to fixing the evo. Keep us posted

 

i have a stock 06 MR and my voltage meter is usually just above or at 14 when im at idle. i dont htink thats an issue. or atleast i hope not

 

i took the car to work today and 1st thru 3rd gear are fine. The car hits 19 to 20 lbs. i shift into 4th and the car hits 25lbs.... shift into 5th and the car hits 33lbs of boost. Any ideas... Ive adjusted the boost controller.... ive replaced the boost controller.... any ideas?