Howdy. I have a friend who just bought himself a 98' Maxima SE(auto) with 77k miles, black on black fully loaded. Everything is great, but theres just one thing bothering him, that I can't seem to help him out with. First of all, this guy is somewhat of a luxury freak. Always wanted a Lexus/Infiniti/etc. but couldn't really get his hands on the right one for the right price. Anyway, to go along with all his leather and creature comforts that he got in this 4th gen, he wants everything to be top notch. For some reason, there seems to be some type of shaking/vibration that he feels during idle that is really bothering him, and something that your regular maintenance doesn't seem to fix. I personally don't pay attention to this crap, but some do. In every gear he is in wether it be P/D/N there can be a slight vibration or shaking felt through the steering wheel and the brake pedal. From being in other 4th gens, I could have swore they had alot smoother idling even with way higher mileage. Plus seeing as it does have 77k(should be low even by 4th gen standards) on it, I really don't see why the idle can't be silky smooth. I even remember on my old 93'GXE, you couldn't even feel it was on sometimes....

So far, a tune-ups been done, and the car seems to be getting all of it's performance. I'll throw in a hint.. Just before the tune-up, the car was eatin so much gas, that he would have to pay a higher gas guzzler tax then a Ferrari Enzo After the tune-up, MPG seems to have gotten a bit better, but the vibration remains. Maybe that can be related? Who knows, but I would really appreciate any seriose feedback. Thanks alot. Basically, just lookin for some silky smooth idle, and from what I hear, thats one of the VQ's signatures.

 

Maybe try a motor vac? I have heard of people saying their cars ran so smooth after they hardly knew it was running. As well you may want to try installing a engine grounding kit, you can make one yourself for under $20 and it just might improve idle and give his auto better shifts.Is the fuel filter good? Ignition coils not throwing any codes? Lastly if he's real picky he could install new motor/tranny mounts.

 

I forgot to mention, clean the throttle body and idle air control valve for sure! Probably will be something that is not included in your regular tune up.

 

could be such a huge list of things its not even funny. Change pcv valve, air filter, new plugs, complete egr system cleaning, throttle body cleaning, new ignition coils, clean the IACV and adjust it, motor mounts could be gone, maf could be acting up. But ya first thing to do is check for codes.

 

I would start with the simple stuff, personally. TB, IACV, check filter or replace, probly already got new plugs with a "tune-up", visually inspect the mounts....u can take it from there...

 

SEA FOAM...............or everthing else taht was mentioned....i would try cleaning the TB first....i bet its all nasty from 7 years of not being cleaned