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Infiniti Q45



  • eagle16eagle16 Posts: 2
    1996 Q45 great car approx 145 k miles. About three months ago, noticed that meleage had dropped from 21-22 mpg to 12+. No sensor lite or warning. After several cans of fuel and injector cleaner and new air filter went back up to about 16-17. What gives? About year earlier had replaced "knock" sensors which markedly improved acceleration. Shop not sure replacing front oxygen sensors will help. Anyone with this problem. HELP.
  • patpat Posts: 10,421
    Hi - welcome. While you are waiting to hear from Q45 folks, why don't you also post in the Got a Quick, Technical Question? discussion. There also are people there who may be able to help.
  • jonsteinjonstein Posts: 2
    Dear Sir:

    I am a new member and by now you probably solved this issue with your Air Bag warning light.

    I had the same problem with my '92 Last Summer and discovered a reset feature built into the car. I found it in my Service Manual that was issued with the car. It involves the driver's door plunger switch (dome light switch etc.) The key is turned on and the switch depressed several times to reset the warning light.

    If you still have this issue, email back and I can give you the details.

    Also, the brake pads have a wear switch built into them and this requires replacement with the pads but is not always supplied with the pad sets.

    I hope this helps if not too late.

  • jonsteinjonstein Posts: 2
    Dear Eagle:

    Have you resolved your MPG issue ? I can squeeze about 15 mpg out of mine in Suburban driving and 22 on the Expressway but many times I can only muster 12 mpg in city driving.

  • mcmahanmcmahan Posts: 1
    I recently bought a 96 Q45t and have two problems. Noisy fuel pump (loud humming) and unstable cornering (very bouncy). The car has 120k on it and wouldn't expect struts to be worn out. Anybody out there have similar problems?
  • qhduongqhduong Posts: 2
    I have a 1995 Q45 and the gas cap indicates "Premium Gas Only". Did anyone try to use regular gas instead? Are there any negative impact or consequences? Thanks.
  • qhduongqhduong Posts: 2
    A loud humming noise in the back of the car, by the rear seats, usually means your fuel pump is about gone. I had to replace my fuel pump at ~135K miles.
  • I have a 1995 Q45a and I always use regular. It probably reduces performance, but I don't need to go 0 to 60 two tenths of a second faster. I have compared mileage occasionally by using several tanks of premium. At best I see no more than an additional 1 mile per gallon, certainly not offsetting the extra 20+ cents per gallon. As for any long term effects, I will turn 130,000 miles this week and the engine has run flawlessly. I'd like to get a new Q or M45, but this car runs so well and looks so good I just can't justify doing it at this time! :D
  • I am looking for a repair manual dose any one out there have one to sell or where i can find one.
  • my problem is when i turn off ignition my car battery gos dead after 14-16- hours i have bought a new 89.00 dollar battery .
    Has any one have any problems like this and what is the solution???.
  • bzbzbzbz Posts: 2
    I replaced the front and rear brake pads and rotors on my 2002 Q45 and when I got finished the ABS, Slip and VDC warning lights were on. I must have accidently turned the toothed wheel rotors and I am seeking some info on how to reset the wheel rotation sensors on the front wheels, possibly if anyone with a service manual would know the position the rotors (Possible location for front wheel lug posts with yellow makings) need to be placed in so the front wheels are in sequence and possibly how to reset the ABS, Slip and VDC lights once the toothed rotors are in place.
  • When you shut off the engine, lift the hood and listen for a humming sound coming from a unit (I believe its part of the ABS system) in the upper left corner of the engine compartment. I've had this unit "stick" both on my car and my wife's '95 J30t. It happens only rarely and amazingly all I had to do was tap it with a hammer to stop the humming. A clue that this is the problem is that your ABS and Traction warning lights are on.

    If this isn't it, you need to look for some other battery drain such as a trunk light remaining on.
  • As a Q45 owner ('95 Q45a) I'm feeling like the Maytag Repairman. Nobody posting here, and August sales of Q45's were 18. As in EIGHTEEN!!! That's not even close to 1 per state.

    When you figure probably 6 or 7 each were sold in TX, FL and CA, no one else in the rest of the country even bought one. Yikes!
  • patpat Posts: 10,421
    Wow - that's miniscule, obviously. I don't ever see any advertising for Q45s, nationally or locally.

    Do you think the M45 is siphoning buyers who might otherwise be interested in the Q45? Or is the biggest issue the advertising. I don't ever see Infiniti advertising anything these days, I don't think.
  • 18 sold in August???

    That is sad. The Q seems like a decent car -- roomy and full of techno gadgets available in all other cars in this class.

    I see Infiniti M ads all over the place.

    You have to wonder though, with Q sales that low why do they bother making them? Or at least, why not support their supposed "flagship".
  • I think the M45 may well be siphoning off sales. I am seriously considering buying one next year.

    I haven't seen any advertising for it either. Maybe its because they are planning a redesign for 2008.

    Here is a link to the sales info if you're interested -
  • Most of the time when this is the case, it is the relay that is at fault, but sometimes the ABS acuator can do this... Most of the times it happens on the 90-93 Q45s, does not seem to be as common on later Qs.
  • I am looking to do the same thing you did, changing rotors and brake pads front and rear.
    I'm afraid I can't answer your question about the lights, but was wondering if you could perhaps give me some advice on how to do the pads and rotors?
    I have not done this before and was looking for some tips if you have them available.
    Thanks for any help you might offer!
  • I have a 1991 Q45 V-8, that had an occassional dead miss usually on hot restart, It would clear up in a mile or two. Suddenly, it is there steady. Mechanic says spark plug well was wet with oil. He only pulled one plug and said ALL coil packs would need to be replaced (primarily needed the rubber spark plug boots, due to being oil soaked.). $2000 estimate. The boots looked like could be cleaned, like they do not soak the oil. There were no cracks, was still flexible. The coil packs are $90 each = $720 in coil packs, on top of 8 hrs labor. He did not have the equip to test WHICH cylinder was missfiring. I told them to put the plugs in, to let me know how many plug wells actually had oil, so as not to be replacing parts unecessarily. I was reluctant to have them do too much since they did not have equip to isolate the dead cylinder in the first place.

    NOW: All new plugs, ($550 minor tuneup) and still have dead miss.
    QUESTION: do these coil pack / rubber boot assemblies actually absorb oil, causing the plug to short? It seems to me they are designed to REPEL oil?

    Prior to this, this car was always dealer serviced (in another state)...

  • elwessoelwesso Posts: 42
    You probably have a bad injector....

    You can test the injectors for resistance and determine if theyre bad. Coil packs RARELY FAIL on the Q..

    read that see what you can come up with. IF you like, print it out and give it to your "mechanic" and have them do that...

    Unfortunate how people think the dealers always know everything about the car.
  • staleystaley Posts: 1
    I have a 1995 Q45. ON my way back from a trip, the fan started making a loud whooshing noise. When I gun it, I get a sound like a belt slipping. I noticed the fan blade is cracking between the blades so I ordered that. My question is should the fan spin freely on the fan clutch because right now it is difficult to spin the fan by hand. I am thinking I may need a new fan clutch. The car is running cool and fine so I don't think the water pump is going bad. Any ideas? Thanks in advance.
  • thank you VERY much for the tip and the link... the miss disappeared by itself... been ok for 100 miles.... must have been the injector, as oil in crankcase has gas odor.... could the injector have been clogged? or was it electrically inop?
  • the belt slipping is probably because the fan clutch is stuck... Ive seen it a few times, but not terribly common....
  • waliswalis Posts: 35
    when tapped, what's to look for? I need to find out if mine is bad as well.
  • can anyone help me? i need to find a fuel pump control unit for a 1993 q45. the dealer is charging me over 600 dollars. i saw it somewhere for 100 but by the time i came up with the money it had been sold. any help will be greatly apprciated. thank you.
  • waliswalis Posts: 35
    hello, did you ever solve the bouncy suspension problem? If so, what did you have to do? Thanks!
  • waliswalis Posts: 35
    Hello all...does anyone know what the problem might be on my misfires on take offs and it's very slow taking off. However, when on the highway, it moves well. I've replaced all 8 plugs with some NGKs. I also cleaned the airflow meter as suggested in one of the posts here but to no avail. I've dumped injector cleaners in the gas tank twice within the last month. I only use premium gas. WHat else should I do? PLEASE HELP!
  • waliswalis Posts: 35 there a place on Qs to check fuel pressure?
  • gode45gode45 Posts: 1
    hi send me the info on the stiff ride fix thanks [email protected]
This discussion has been closed.