Possible MAF…help??

[Squiz]

I drive a 1997 QX4, 4x4, automatic with roughly 113K. I’m attempting to diagnose an issue I’m having with acceleration that I feel is either MAF, injector or throttle body related. I’m not a mechanic or technically knowledgeable beyond general repairs and understanding.

ISSUE:
Driving around town and even at freeway speeds the rig is responsive and feels perfect. It’s when going up a large hill or attempting to pass someone on the freeway that this issue comes to light. Stepping on the accelerator, I can feel the car downshifting and the tachometer jumping from 3-k to 5ish-K, but the power isn’t really there. I can feel the car pulse or throb in a rhythmic pattern until I let off the gas. If feels as if the injectors are being starving of gas or air and combustion is malfunctioning.

Any insight on the issue from your experience would be greatly appreciated. I’m trying to also avoid the hefty stealership fees.

Thanks for the help! [*]

[Densetsu]

First thing that comes to mind is the fuel filter being clogged. I've only changed them on the R50's, but if the '97 is anything like it, it's a quick, cheap, and easy fix. how-to-change-the-fuel-filter-r50-t459800.html

[Towncivilian]

Fuel filter also sounds like the cause. Densetsu, a '97 QX4 is an R50 and the process is identical to change the fuel filter, even the fuse for the fuel pump (see MA-13).

[Densetsu]

Fuel filter also sounds like the cause. Densetsu, a '97 QX4 is an R50 and the process is identical to change the fuel filter, even the fuse for the fuel pump (see MA-13).

Whoops, brain fart on my part, haha. Different engine, but same generation.

[Towncivilian]

Fuel filter also sounds like the cause. Densetsu, a '97 QX4 is an R50 and the process is identical to change the fuel filter, even the fuse for the fuel pump (see MA-13).

Whoops, brain fart on my part, haha. Different engine, but same generation.

Yep. The fuel filter in WD21s is in the engine bay. I guess the bullet point "Be careful not to spill fuel over engine compartment. Place a shop towel to absorb fuel." in the R50 FSMs is a holdover from the WD21 FSM. But I digress.

[Squiz]

Well, this certainly sounds a lot less intimidating than I originally thought. I was pretty convinced I needed injector cleaner or some God awfully expensive part.

Thanks for the posting the step by steps!

[ARKQX33V6]

At the same time that you do a fuel filter change with a 97QX4, have extra fuel line . If you have not changed the filter in a while, the lines on the filter will be busted up, so renew them. They get mangled trying to take apart, you can cut them shorter but just in case have extra on hand.

At the same time your just before you change the oil, clean the throttle body. The MAF sensor with this year should not need cleaning, as long as you kept a clean air filter. The air filter should be pulled out and looked at with a bright light, if dirty replace, but every 3 moths pull it, dust off and inspect.

I change the fuel filter every 2 years to maintain fuel pressure in the fuel rail.

Check you timing and advance mechanisms for sluggish movement.

[Squiz]

This is great advice, thanks! My air filter is clean, so no issue there, but I'm unsure how to clean the throttle body.

What brand of fuel filter do you recommend, I see they range from 10bucks to 25? I'll also search for the fuel lines as well..are they easy to install?

At the same time that you do a fuel filter change with a 97QX4, have extra fuel line . If you have not changed the filter in a while, the lines on the filter will be busted up, so renew them. They get mangled trying to take apart, you can cut them shorter but just in case have extra on hand.

At the same time your just before you change the oil, clean the throttle body. The MAF sensor with this year should not need cleaning, as long as you kept a clean air filter. The air filter should be pulled out and looked at with a bright light, if dirty replace, but every 3 moths pull it, dust off and inspect.

I change the fuel filter every 2 years to maintain fuel pressure in the fuel rail.

Check you timing and advance mechanisms for sluggish movement.

[Towncivilian]

I'd go with an OEM fuel filter, should be around $14 from your dealer.

[Squiz]

Should I expect to see an increase in fuel efficiency with the filter/hoses replaced? And lastly, when buying the hoses, can I pick these up at the dealer as well (OEM) in the correct length, or should I purhcase something I can cut down?

Again, thanks-

[Towncivilian]

I did not experience any fuel economy increase, but mine was not clogged to the point of bogging things down, so your experience may vary.

I believe you can just use any fuel line hose that is the correct diameter (I don't know what size ours is).