94 Q45 - Transmission problem???

[Ted]

I would like to get your opinion on the problem I recently been having with my car. It is a 94Q45 with about 98K miles. I had a major tune up and transmission flush at 90K.

Lately, I notice that there a lag of thrust when I between 15-30 miles driving. What I am trying to describle is, for example when I make a right turn, of course you have to ease off the gas pedal during the turn, when I start stepping on the gas pedal again after exiting the turn, I notice a lag of a second or two before the transmission would engage.

I notice it only happens when the car is coasting. But when I start the car from a red light, the transmission shift smoothly without any hiccups.

The engine idle seems smooth. I live in CA. I am not sure if the new gasoline with a mixture of ethonol has to do with the sluggish start.

If it is a transmission problem, how much do I need to spend to fix this?

I appreciate your opinion.

ThanksTed

[elwesso]

Sounds normal to me.... The transmission doesnt always downshift unless you make a complete stop, so youll be going in 3rd or 2nd gear... When you feel it engage but still sluggish is going into 2nd...

Sounds like your Q could use some work as well.... Knock sensors and such..

[Q45tech]

An 11 year old transmission is an old transmission even with 100k but we see them with 250k at that age [94-95Q].

What was done every 3 years from brand new vs what was done 6 months ago is the determinate factor. How did th ATF look prior to flush.

Probably the usual DIRTY ENGINE situation: plugs, knock sensors, FILTH in intake air tract, injector deposits.

If it's transmission expect $3,000 + [CA dealer prices might be $4,000] for factory remanned unit.

Have dealer do COMPLETE diagnosis.

You really shouldn't feel the Ethanol, just show up in lower MPG as the accelerator needs pushing 3-5% farther down.

[louiegz]

I had a tune up and transmission fluid changed at the dealer a few months ago. The first two weeks, the Q drove a little sluggish. After that, it drove fine. A friend of mine drives a 03 Acura TL and the dealer told him that when you have major work done on the TL, it takes a while for the car to adapted to the way you drive again. I wonder if the Q was so advanced in the early 90's to have this adaptive style computer in the car. I'll tell you one thing, my car never has enough juice off a right turn. You start to make the turn in 1st gear, and half way into the turn, the transmission goes to 2nd. Forget about it if after that right turn, you have to go up a hill.

[elwesso]

Sounds like BOTH your cars are the usual suspects... Bad KS and dirty intakes and such...

My Q (which runs PERFECT) has no problems climbing hills in 2nd... YES we do have a few hills in indiana...

[louiegz]

Sounds like BOTH your cars are the usual suspects... Bad KS and dirty intakes and such...

My Q (which runs PERFECT) has no problems climbing hills in 2nd... YES we do have a few hills in indiana...

Sorry Wes. Had those taken care of in my last service call. Read this tread. http://www.nissaninfiniticlub....64194 The Q in 2nd gear at 2000 rpm just doesn't have good uphill power. We have some big hills in NJ. Once your past 3500 or so then it flies up the hill. I've always wished I had another Q to drive for comparison. Mine is the only Q I've ever driven. One day I will have to go to a meet.

[elwesso]

I see NOTHING in there about knock sensors..... Unfortuntaely all those things would have hardly anything to do with the performance...

The 02 sensors maybe but nothing else IMHO......

[maxnix]

I see NOTHING in there about knock sensors..... Unfortuntaely all those things would have hardly anything to do with the performance...

Even if the timing was being retarded and it was running even richer?

I don't experience a similar problem on either of my G50 as I can punch it hard enough to break the rear end loose on any left or right turn if I am not judicious with the throttle.

[louiegz]

Cmom, changing the plugs doesn’t affect performance? As far as the intake, I changed the air filter when I did the fuel pump myself in April. The Q was sputtering in to the dealer before they fixed it. They did a consult. If my Q needed KS, wouldn't the consult pick it up? Remember, I drove this car the first day it came out of the dealer, when my father purchased the car for himself. Since new, the Q has always had dead spots at low rpms and choosing the wrong gear. That's just the way this car is.

[Q45tech]

At 2,000 rpm there is little reserve [above AC draw] for climbing hills, why it first unlocks the TC then down shifts to a lower gear.Every single pound feet of torque is critical for every foot of incline.Being down [off] by 10% will be noticeable. Obviously worse in Summer when the power is down natually [5-10%], add the 3-5% loss of ethanol and dirty plugs, intake and you are off by 20%.

[elwesso]

Brian, in his message in that thread it said he was running LEANER!!!!!!!

[maxnix]

I don't know louiegz, mine are both 1995 and they have just 10K (with 60K service) and 20K (without 60K service) less miles than yours does.

[louiegz]

I don't know louiegz, mine are both 1995 and they have just 10K (with 60K service) and 20K (without 60K service) less miles than yours does.

Don't get me wrong. When it's still in 1st gear and you make the turn, there's plenty of power on tap. I'm saying when it goes to 2nd, way too early, that's when the power isn't that good. If I hold it in first and gun it in a turn, my TCS will light up like a Xmas tree. When you take the turn and your light on the gas, midway into the turn it goes to 2nd and not leaving you with good torque. That's why I like cars with manual trannys better. I like choosing my gears.

[maxnix]

Ah, the TCS word! Don't know about that (thankfully). Seems like I can hold it in first as long as needed, but I will have to find someplace to run it out in second gear. Freeway ramps never seem to be a problem that I remember. I especially like the dual entry lane ones.

[louiegz]

Ah, the TCS word! Don't know about that (thankfully). Seems like I can hold it in first as long as needed, but I will have to find someplace to run it out in second gear. Freeway ramps never seem to be a problem that I remember. I especially like the dual entry lane ones.

I know TCS is a pain, but with NJ winters and the snow and ice we get, the Q would be useless. Even with TCS, you still need good snow tires.

[Q45tech]

For fuel economy sake they up shift as soon as possible.

Toyota has the economy/power button and the JWT TCU trimode had 2 positions 1st gear start economy/power and 2nd gear start.

I always leave mine in 1st/power mode which holds the gears longer vs road speed.

The up shift is a function of TPS voltage [engine load setting] and speed............short of a software reprogram you are out of luck........might check hot idle TPS voltage and make sure it is 0.44 volts +- 0.05 volts. You could experiment up to 0.55 volts and see if that helps some [?????????].............the 22-25-30 mph no down shift to 1st gear speed limit to save the transmission from abuse.

[Ted]

Thank you for all of your input. I will take the car in for a diagnostic.

If it is really the transmission, I am not sure I want to spend 4K to replace it, since the blue book of the car is only 5-6K.

Ted

[maxnix]

If it is really the transmission, I am not sure I want to spend 4K to replace it, since the blue book of the car is only 5-6K.

Ted

Aye, that's the dilemma; spend the bucks to maintain them like they were when new and save the bucks lost from the rapid depreciation, or be in financial prison and drive it into the ground since it will die from lack of maintenance which must exceed the 'book' value of the car at some point.

I usually resolve this by asking myself what I would rather have and what the financial impact would be in comparison to repairing it. Usually I am stumped by the first question, and if not, then the second brings it all rapidly into focus.

[elwesso]

The way I justify spending half the car's value on maintenace is basically Im owning a 50,000 car for $5500, and with no payments... So all I have to do is keep the car running, and I dont have to worry about payments on it... To me owning a G50 and just having the maintenance seems like a stellar deal to me... I dont even think I could own a brand new or newish honda for as cheap as I can own the G50...

of course doing all your labor yourself helps!

[90Q45blue]

of course doing all your labor yourself helps!

Very true. When you're mechanically inept (as I am) the Q is more expensive to maintain, but I use the same justifications as Brian does and come away very happy. A road trip helps

Nick