Hi guys, just want to share this. Thanks by the way to zix8888 for giving me advice on what to look out for when bringing in the car for the event described below.
Three days ago, I had DMC in Valle Verde look into the check engine light (CEL) indicator that lit up in the instrument panel. They only managed to make preliminary assessment and cleared the visual alarm. They did pinpoint the source of the alarm to "fuel exchange filter failed" which I later knew to be trouble code P1276 (TC P1276) using their diagnostic software on a laptop which was connected to the data terminal in the car. They asked me to bring back the car if the CEL lights up again so they can change the fuel filter. Indeed, yesterday the CEL lit up again.
I'm much nearer to Mitsubishi Carworld Malolos so I brought the car to them today, instead. Carworld used the findings of DMC and they did the following procedures:
1. took sample of diesel from the filter. they observed presence of water
2. they pulled down the fuel tank, with all 70+ liters of Petron diesel in it.
3. drained the tank
Here is a photo of my fuel tank being drained of water-contaminated diesel. Frankly I can't tell the difference. but then again, they are the experts.
4. check for rust outside and inside tank (none seen)
5. check fuel "passages" from the fuel fill cap to the sensors for rust and contamination (none seen)
6. bought new 20 liters of diesel from Caltex in a clean container and refilled tank
7. only then did they replace the fuel filter
8. hooked up the laptop and software. Cleared P1276 and run diagnostics again. No troubles found.
9. computer recalibrated the injectors and all the other stuff automatically through software
A snapshot of the the laptop's screen while performing diagnostics.
10. road test.
All in all, I think Carworld Malolos did a good job in solving the problem by addressing the root cause and not simply changing the fuel filter. That said, I hope that's all there was to it and no other trouble will surface for the time being. fuel filter cost (P1,134.00) including labor, misc and vat totaled P2635. Madumi na din actually yung lumang filter. May nakasabay akong Montero, binaba din fuel tank at kasing dumi din yung fuel filter. I didn't ask but I think, nag CEL alarm din yung kotse nya.
I also observed there were a bit of rust on a few spots underside of the car. So my next job for it would be full rustproffing. In the meantime, sa Caltex diesel naman muna ako.