4JB1T howling noise

**knight23** · June 21st, 2005 08:41 AM

i have an isuzu fuego w/ the 4JB1T engine, and when it reaches 3,000rpm, it makes a howling noise. the howling noise disappears though when i rev it more.
does anyone have an idea on what is causing this howling noise. btw, it's almost 25k on the odometer and is up for an oil change.

thanks

**ARB** · June 21st, 2005 08:56 AM

might be the turbo spooling up. is it the same sound if I hatak mo ang third and fourth gear up to the redline?

**voltscastillo** · June 21st, 2005 09:57 AM

turbo operation for diesels is almost transparent to the driver. my pajero's 4d56 turbo diesel would engage at 2500rpm (factory present) and would give power up until 4500rpm (500rpm below redline).

pero nung masira na yung turbo some time later, i started hearing a howl at 3000-3500 rpm, getting progressively louder, and especially when you floor it, parang may gas na na-eescape sa makina. i'll lose power bigla.

turns out it was a malfunctioning blow-off valve sa turbo. it makes a weird noise pag sumisingaw below the preset limit. knight23 you may want to look at this first before sticking your finger up the turbo blades to see if they're still ok. else, get your fingers ready to jimmy the blades as per usual m.o.

**knight23** · June 21st, 2005 12:34 PM

been having this problem for two weeks now, its a come and go problem. today, nawala yung noise. there's a howl between 3,000 to mga cguro 3,250 rpm in any gear even when parked

but beyond that wala na ang howl. i'd have it check when i'm going to have a have change oil.

currently having lots of minor problems w/ my fuego, rattle in the door, rear seat and dash, aircon not functioning when in idle for a while.

thanks for your responses.