giolex300

whats up everyone. car runs like a champ when in park. accelerates fine, revs fine (about full throttle), no signs or hear any vac leaks, dont smell gas either.

the moment i put it in DRIVE and press throttle car bogs out. i havent checked my MAFS, throttle body yet or cleaned it. and the reason i havent cleaned it is because how it runs when in park, runs fine. i heard it can be the fuel filter, but heard it doesnt need to be changed because its a lifetime filter, never needs to be changed. (correct me if im wrong). the rubber seals for the filter lexus doesnt seem to carry them, so if i screw up im fu@#$. ill cross that bridge when i get there so im holding back till i get a definite answer.

thanks for your time.

GS4_Fiend

iTrader: (22)

Do the basic maintenance first and see what happens.

jcat_350

air filter, spark plugs, fuel filter (it's not lifetime, no car part is), run some fuel cleaner through a tank.

By placing the car in drive you're inducing load on the engine. Anything affecting air/fuel/spark will be exacerbated under load. this is probably why it's not noticeable when in park but bad when driving.

Could also be cam sensor or crank sensor, but not likely as these would affect starting the car and or running in park. Other things that may be causing this could be o2's but you'd get a CEL, MAF, or sensor problems.

Most times if the MAF goes bad, it won't throw a code because it doesn't know it's not bad; it will just take the readings it's getting as true and make the car run like crap. See if you can get a known-working sensor and swap it in to see if that's the issue. Since it's load-dependent, this is where my money's going.

giolex300

thanks for the input.