throttle body block plate...

i'm sure many drivers using fuel injection engine do had some difficulties with unstable rpm whenever the aircond kicks in... this is because the ISC (idle stepper control) unit which is located below the throttle body has damaged... particularly for MMC engines, the ISC unit breaks down frequently and it is expensive to service in long run... ISC repair kit can be bought from spare part shop... it consist of a few plastic gears inside the ISC unit...



however, this does not solve the melting problem of the ISC chip because it rests on the hot coolant hose running at the bottom of the throttle body...



hence, they came up with this alternative solution...





it blocks the coolant passage in the throttle body... means u no longer run coolant into the throttle body as it is deemed unnecessary in hot tropical countries... the plastic ISC chip remains and it activates the stepper function whenever aircond kicks in... the disadvantage is, at Rm150 per unit it is rather expensive and it is still made of plastic and it does melt or damage sooner or later...

one more solution which always been mechanic's recommendation is to use Toyota AE101 FICD (fast idle control device)... this electrically actuated valve can be adjusted to allow any given amount of air leaked into the engine to bring up the engine revs up to desired speed...



on my current setup, i have 2 units of FICD to control the aircond idle revs and cold start idle revs individually... with this, the ISC unit can be removed all together...

i had some spare aluminum plate lying around left over from my FYP project... took out my old throttle body, removed the ISC unit and did some measurement...



sent the measurement and the aluminum plate to machine shop and this is what it came back...



i made a paper gasket to properly seal it air-tight... i also swapped the notoriously-difficult-to-remove screws and had them replaced with allen key screws...

tacho tacho tacho...

i could not recall when i bought this tachometer from JASMA... it has been on my desk staring at me collecting dust as far as i can remember...



initial purpose buying it was to replace my crazy OEM tachometer "which occasionally gets stuck at 3000 rpm"... my plan was to cut away the OEM rev counter and retrofit this aftermarket gauge into the meter cluster... however it is much harder than expected, as there are more complex PCB at the back in which i would want to retain using certain OEM indicators...

wiring installation was quite simple... there is only 4 wire from the harness... 2 12vDC, 1 negative and 1 signal input... signal input i tap from existing wiring from the socket behind... for iswara OEM socket harness, white wire is the rev signal coming from the ECU...



it has a preset warning shift light at 6500 rpm... the reading is accurate for now... only thing annoys me is that it is not clearly visible in day light...

direct pipe??...

in my previous post on head work i did mentioned of lacking some throttle response as well as mid-high rpm gain... in the midst of complication to get things right, i did something stupid... haha...



yeap... 1 direct stainless steel pipe to replace the stuffy WISE muffler... end result, very empty and torque-less low end... mid-high rpm was orgasmic, especially when the needle swing pass 4000 rpm... the noise??... wonderful and at the same time, nuisance... haha... lifting off the throttle at high revs can result in misfiring "popping" sound...

used it for 2 days, i swapped back to my old straight flow muffler...



this muffler creates just enough back pressure for reasonable power and torque across the rev range...

new amplifier...

i had my car amplifier changed a couple of months back... the old one was faulty at one of its input channel...



i replaced the old amplifier with this one... VOLCANO 1000w 2-channel amplifier...







i admit i'm not a big fan of In-Car Entertainment... hence, i bought this cheap ass amplifier to replace the dying one...

head work...

still remember the ported cylinder head I'm using previously??... the ports are rugged and no polishing job was done to the surface... the valve guides were also badly ported, which might allow the valves to vibrate under high engine revolutions...





finally after 4 months sending my cylinder head to workshop for port and polish job, it has finally returned... but with just the porting job done...





i DIY'ed polished the cylinder head valve throats with some sand paper and autosol... did some shopping for new top set kit, viton valve seal, timing belt kit, water pump and other necessary fluids...





head swapping was done at workshop... left my car there for a day and got it back the following day... what makes this newly ported and polished cylinder head different compare with the old one, the engine revs up more smoothly... there is no minor jerks and hesitation which i experienced with the old cylinder head setup... however, the downside i lost a little bit of throttle response and torque... this is probably because the cylinder head was not ported big enough...

my mechanic also overtightened the aircond compressor belt, causing very high pitch screeching sound... crankpulley and emitting strange grinding noise... most probably due to improper installation... always remember, do not take your attention away from your car when it is at the workshop... u'll never be sure your mechanic did the right thing... or he might had passed the job to his junior to handle...

overall was not very satisfied on the performance... but i gained precious knowledge and experience trying to assemble/dismantle the valvetrain and porting and polishing it... i dont think i will be taking it out and redo the port work again anytime soon...