Strange idle problem...

[climbinglife]

Hey guys, I did a search but couldn't find to many people with this problem:

I've owned my 03' pathy for around a month and the only constant problem I'm having is a steering wheel vibration when the car is in any drive gear and my foot is on the brake. The engine is has no mods...55k miles on it.

I'll summarize:

Once the car is fully warmed up, at a stop light or in traffic, while in any drive gear, the car's idle drops to say 600-650, and the steering wheel vibrates. Once i accelerate, it's smooth as silk. The isle is NEVER rough, even when it drops it's solid at whatever rpm it drops to. No fluctuating or surging.

If I shift to park, or neutral, the idle rises to say 700 and the steering wheel stops vibrating. Just the steering wheel shakes, but it's enough to be annoying. When you go from Neutral to drive, you can see the rpms drop 50-75 and the vibration starts. Back to N or P and the idle rises and it goes away. The motor mounts were checked and are fine and tight. I really like the truck and this is the ONLY problem I've had which i either deal with when I'm stopped or in traffic or I just shift the car into Neutral when i'm stopped. I mean i'm not gonna buy a new throttle body as I heard they are expensive and I haven't brought it to Nissan yet as I wanted to get a heads up on things it could be and after I did the cleaning on the TB & MAF.

Things I will be doing next week after some reading here are the MAF & Throttle body cleaning as well as changing the fuel filter. I read somewhere about the "power valve screw" but not sure if it applies.

We are talking a very small drop in rpm's but it is enough to cause the shaking in the steering wheel.

Thanks for any help!

Regards,

Vin

[Towncivilian]

I also notice this vibration in the steering wheel at idle in drive sometimes, but it does not happen all the time. I believe it may be normal. If you turn the A/C off, does the issue go away?

In addition to your MAF and TB cleanings and fuel filter change, try running some Chevron Techron Fuel System Cleaner.

[climbinglife]

Actually, if I put the A/C on, the idle rises a bit and the vibration is much less noticeable. My problem is specifically with the A/C in the off position.

I will add the cleaner...thanks for the heads up.

[Towncivilian]

You may also try idle air volume learning, described on page EC-81 of the factory service manual.

[climbinglife]

Alright, tried all of the above, except the idle relearn, to know avail.

Is that something I need to have done at a Nissan dealer?


I gotta say I love everything about this truck but this issue is supremely pissing me off.


I'm wondering if it's in the drive train maybe, because it's in gear? But I'm not moving...

[Towncivilian]

You can perform the idle air volume relearning yourself, it's not a very difficult task. Steps are outlined in the FSM page I mentioned above.

You may also wish to inspect the engine and transmission mounts, perhaps one is worn and transmitting excessive vibrations somewhere.

[climbinglife]

Didn't realize that...i'll check again, thanks. Motor mounts were inspected and they are fine. I'll have the transmission mounts looked at.