1999 Q rattle pass. floorboard

[poweroptions]

On my country gravel road I hear a rattle that I can best describe as a small block of 2X4 thats loose. The sound comes from the passenger side behind the front wheel I think. It happens under 20mph as I hit small pot holes in the gravel road. I've been under the car and see nothing out of place and everything is tight under the hood. Q sits at 50K, ideas? TY

[paranoidjack]

None, 150k never heard anything like that.

[maxnix]

Well, no suspension maintenance history offered, so all we can do is guess which is not very helpful.

Start with strut inserts, bearings, tension rod bushings, front sway bar links.
Modified by maxnix at 7:06 AM 6/23/2008

[poweroptions]

the car has not had anything done to the front end. I notice the accordian boots on the struts are disenigrating and that's all I can see. No oil leaks or other damage. I had it jacked up with weight off front wheels and all seems very tight, I can not see much wear on bushings anywhere. The knock/rattle is not continuous it occurs just once on every pothole in the county road. Maxnix, do you know of any mechanics in east Texas? I lost coinfidence in Sewell, last time in they forgot the engine cover, forgot to tighten the battery holder inplace and left all the nuts off the air induction across the radiator support. Strangely enough the rattle started after i picked it up this last time at Sewell. Of course they claim they know nothing. They did send my engine cover back FedX along with other nuts and bolts they forgot to reinstall. I desperately need some one to help me on my Q no one here in east Texas is knowledgeable.

[bullittandy]

Sounds like a strut mount, maybe a tension rod or sawy bar endlink. Any competent suspension pace can likely find the source.

good luck!

[maxnix]

No, competent Infiniti Technicians are very rare. But for your problem, as Andy has said, any competent ASE certified technician should suffice.

I would start with the tension rod bushings, for surely they are gone. Is there no sign of leakage at all? Roll bar bushings and end links can be inspected for deterioration and replaced easily. Don't neglect the steering rack bushings and check the endIf those don't cure it, then you are going to have to disassemble the front suspension and replace the gaiters, bound bumper, and top strut bearing, maybe the spring seat.

FA-6 in the 2000 FSM and on will tell you how to diagnose and repair. FA-17 shows the parts.

Order those parts from Joe so you have them on hand after the inspection.

http://www.infinitipartsusa.com

If you don't have a complete copy of the Infiniti Dealer performed service history on your car, have your "favorite" service person from Sewell pull it up and print it out and send it to you. Sounds like Sewell let a minimum wage grease monkey parctice on your car. Why the inlet snorkle is off for a front suspension inspection is unknown to me.

At eight years, a lot of deterioration of the rubber has taken place. Maybe even one of the struts has partially failed without you noticing it?
Modified by maxnix at 12:06 PM 6/23/2008

[poweroptions]

I'm going to jack it up again and go looking. Grrrrrr sure alot of things going wrong on my car. Remember this Q has been to the shop 7 times for this damn rear O2 sensor. Its still screwy and the SES is on. Car runs fine but I swear the gas mileage goes down when the SES is on. That's why Sewell had all this stuff loose up above. Hell a week went by before I opened the hood, only to see things missing. I called NGK Co. too and spoke to a tech and he said my replace from Sparkplug.com was the exact match. Sewell was telling me I had to spend 600+ to replace both O2s that the NGK was not up to snuff. Sewell would not quarantee this would solve it and more repair might be expected. Cripes the car has 50K e z miles. WTF and to chap me more when this all started going screwy with the o2 it was still under warranty, now a year later it's out of pocket for the Sewell guesswork. I decided to drive the car with the SES on and maybe it will throw other codes to know EXACTLY what the problem is. So far as of yesterday still showing code 0138/rear02. I just drove the Q to ferry folks to Love Field. I notice the block of wood is making more noise. I have a good front end shop here in Athens. The car got 18.8 mpg w/ac on 65mph. Not real good I'd say. I can work on every car I own but this ones screwin withme.

[maxnix]

Ohm test your knock sensors. How is your gasoline? Are you using BG44K before every oil change? Recent fuel filter change?

Still don't know why CAI snorkle would be undone for O2 sensor service.

Sure you replaced the correct one? If so, you might consider replacing the other also.

[poweroptions]

All of our gas has ethanol here in Athens/Tyler. I took your suggestion months ago and runBG44K thruthe Q now. I think its what stopped the erratic stumble at idle. I was changing fuel filters on the John Deere today and thought I'd order one for the Q. It was kinda weird back from Sewell,cover was missing, nuts missing on the snorkel the battery cable wasn't tight nor was the hold down, the fascia underneath still doesn't have all of its bolt back in place. I think they forgot to tighten them and half are missing. I just noticed something hanging under the car a few days later. So as I say, I lost faith in Sewell this last trip. Do you have a mechanic in Austin? I have never ohmed a thing to the best of my knowledge. When you say replace the other Brian you are referring to the front 02. Andy has spoken about the coils I thought maybe I should replace all of them on that bank, since that is the bank I have the ongoing 02 glitch. Your thought? Those paks are $$$ I just checked out Joes sight and will take more of your advice and get my parts thru him. ty

[maxnix]

Yeah, good help here is also difficult to find, so I try and do as much diagnosis as I can myself. But someone needs to Ohm test your knock sensors.

Don't know about replacing all the coilpacks on one bank is a solution to much. But matching the duty cycle with another new primary O2 sensor might help, but may not. You have to look at the wave forms to see how lazy the other one is.

What was dangling?

When you order a couple of fuel filters, get air and cabin filters also.

[poweroptions]

The big black piece of plastic that covers the underside of the engine and the coupling for the 02 they had been jacking with. They had managed to break the harness clip and it was allowed to hang down with no attachment anywhere. It was the plastic cover i first saw walking back up from the barn, i couldn't figure what was under the car. I had driven it several days and the bolts I think vibrated out, thats when i opened the hood and things were just flat out gone. I called Sewell and told them they'd be replacing everything with new parts. I got most of my cars parts back minus 4-5 bolts couple days later. I used a plastic zip and put the 02 sensor back up where it should be. Gggish Now I'm just flat out pissed at the car for SES idiot light on and I don't know for sure why and its 10,000 miles later nearly and 3 service shops later nothing is different, except with everytime someone works on it something is screwed up. I work on my old benz and fords but this Q is not the same.

[poweroptions]

Brian, i didn't screw something up by putting the 17" factory 5 spokes on a regular Q. My Q had the standard wheels that looked like my 300SDs. To make it look sportier i put the 17s on it with yokohomas

[maxnix]

Nah, I run 18".

If I were you, I would make arrangements with Sewell to reassemble your Q45 with OEM parts the next time you go to Dallas. The service manager should be aghast as to your situation. Might drop a hint that if he rebuilds the car to the specicfic condition in which you presented it for service you may not have to call Infiniti Customer Service. Actually, going to the area service rpresentative with your problems and Sewell's inability to diagnose and repair it would not be a bad strategy.

The FGY33 is really a pretty simple vehicle on which to work. You just need to read the FSM and follow the procedures.
Modified by maxnix at 5:02 PM 6/23/2008

[bullittandy]

Your 17" wheels didn't hurt a thing.

If you have a stumble at idle then I swear that this is a coil problem.

the suspension noise is very likely a wear item and every time I've heard a noise like you've deribed its been a sway bar link or strut mount.

If you like this car then spend the money and replace evrything-you'll love the car again.

[poweroptions]

I have the car jacked up and blocked and have been under it an hour studying thing. Got my reading glasses on and my troublelight. I sure as hell don't see a single bushing with wear problems everything is super tight and the tires are wearing excellent. I am searching for a tool or something that might have been dropped from up above as this clunck started on the trip home from Sewell the last time. You think I should replace the front o2 thou no code showing? Why would Sewell not have checked the wavelength, I paid for SES diagnoises, is this wavelength thing hard to do? I myself have NO IDEA what that means. Brian thanks again,pat

[poweroptions]

you know i have had no stumble the last 5000 miles since i ran a can of BK44 in it. when the ses is on i'd swear it's not as quick. i pulled the old 02 out of the box that had been replaced and with glasses i see it was a bosch. i am ordering another rear 02 from Joe I guess, I see this NGK is different in appearance. Man I was looking at the front 02, I need skinny japanese arms to get to it, i'm a cornfeed white boy. I'll replace all my filters, replace the rear 02again(code0138always on/code0139(once). I can't afford, or trust the dealership. The rattle i'm thinking is in that rt/frt wheel instead of tapping once it's now rattles 2-3 times on a rut. I do not feel it as feedback in the steering wheel however. Yeah I have been really impressed with my car. I spent 3months finding the one. I bought this one with 33K a couple years ago. I hit 40k and the quirk with this sensor started. I just turned 51,000 on the way to Dallas today. Andy thanks for your ear and thoughts,pat

[maxnix]

I doubt seriously they hooked it up to a scope and may not have anyone able to read one if they even have one.

Did you request the senior Infiniti tehcnician work on your car, presuming they have a genuine one?

Strut bearing won't show with pressure on it. Read the FSM where I recommended.
Modified by maxnix at 12:55 PM 6/24/2008

[bullittandy]

I have the car jacked up and blocked and have been under it an hour studying thing. Got my reading glasses on and my troublelight. I sure as hell don't see a single bushing with wear problems everything is super tight and the tires are wearing excellent. I am searching for a tool or something that might have been dropped from up above as this clunck started on the trip home from Sewell the last time. You think I should replace the front o2 thou no code showing? Why would Sewell not have checked the wavelength, I paid for SES diagnoises, is this wavelength thing hard to do? I myself have NO IDEA what that means. Brian thanks again,pat

Don't worry, the reason you don't know what "that" means is because its made up techno-babble!

O2 sensors are wear/maintnence items and so you will lose nothing by changing them and you may even gain something. Its not a bad idea to change them to rule them out.

That being said, if you have changed the O2 sensor and have the same code then something else is wrong. Maybe the connector on the O2 or maybe the engine computer or maybe its correctly reading something that is out of tune on the engine like a misfiring cylinder dumping fuel into that side of the exhaust.

Change the O2 sensors, maybe the knock sensors as well and find the misfiring cylinder and fix it and I bet the light will stay off.

[poweroptions]

I've ordered new O2 sensors front and rear, plus filters, plus new brake pads. Call it the 50,000 mile checkup. Anything else I should do? I've replaced thre plugs thou they didn't need it. It was to fix the stumble earlier and my house mechanic assumed it was plugs, it wasn't. The rotors will get turned since the Q started pulsing when brakes were applied. Guess I hit water and the rotors were hot and they warpped. I sure don't drive it hard or brake hard. This was just something else to fix at 50K. The front end goes to the shop next week to be checked out. I hope this does it up for awhile. I will check in later once all this work is done and we will see how it goes and that the quirks are remedied,(I hope). pat

[maxnix]

Hopefully he used the pfrg5 or 6 NGK plugs.

Nissan front rotors in particular will require turning every 30K or so. I recommend the Stillen Brembo ones Joe sells occasionally on special. OEM pads. Also replace the brake fluid with a good DOT 4 like Syntec.

I would invest in the front and rear suspension wear items now (all rubber isolating components including steering rack bushings) as you will need them at some point, and one of them is surely your cause of thumping. I suppose you can wait on th e front cartridge inserts, but I would not be surprised that you find one has failed at least partially.

I find that the Tire Rack installation shops usually have the experienced owner techs with the Hunter algnment machines that really know their stuff. Check the ratings and interview the top 3 in your area. You should be able to tell whom to trust.

Print out the tests in the FA section of the manual so the shop does not have to rely on Some Data like most do. It's never as complete, thus my name for it.

[poweroptions]

Ditto, I got the right NGK plugs. Bought a backup pr. of Bembo rotors for the front, however surely the originals can be turned surely. Joe has all the right side o2s and filters in route. Is it possible that when the SES is on the car sounds different? I hear a tick like a clock from under the hood and then there was a weird buzz the other night when I put it in the garage, The buzz started when I put it in park, I got out looked and listened under the car and it was coming out of the transmission, the car was running. I got back in shifted it thru the gears and put it back in park and it had quit. Gremlens I suspect. Well the old reliable 300SD is down seems the aux fan won't come on so Benz is running next to the red zone temp wise. I turned around and made a beeline home. Fan works fine, checked it direct to battery. Must have a temp sensor or relay somewhere. Out come the service manual for it now. However I'm not imtimidated with the old Benz like I am the Q.

[maxnix]

Be aware the stock Brembos are not plated, so they rust like and anchor. They also are much better than the stocks for staying true longer. Be sure to turn the rear rotors and use new pads also, The rears if not true can cause the fronts to become untrue.