1990 Q45 transmission clarification
1990 Q45 transmission clarification
I was hoping to get some clarification on the actual nature of the early Q transmission woes. I know that the turbine sensor are often faulty. Any other problem ? I hear people refer to "blown tranny" but what parts ? My current transmission is having a hard time shifting into higher gears and at times may not shift into third unless I release the acceleratore for a few seconds. Otherwise there is no slippage or whine or leak. car has 145K on it with appropriate fluid changes... I ran the tranny self diagnostic, but it came out "OK" despite the improper shifting. does this sound like the turbine sensor? and if so should I just replace that and leave the rest of the tranny alone and save myself some money.I would appreciate any input or thoughts on this matterthanks.
Maybe you are having trouble getting the line pressures up for teh shift.
It might be a good idea to Flush and then pan drop (with new filter/screen MUST have that, even if dealers claims it's "lifetime")
Do it soon before the lower pressures take out the rest of teh tranny (assuming this is the isssue others may chime in with other possibilities).
Fred...
It might be a good idea to Flush and then pan drop (with new filter/screen MUST have that, even if dealers claims it's "lifetime")
Do it soon before the lower pressures take out the rest of teh tranny (assuming this is the isssue others may chime in with other possibilities).
Fred...
RE: Blown transmission parts
I have had two blown transmissions on my 90 Q. The problem with the early Q trannys is that the entire unit is made of metal gears, etc. so when a gear breaks it shoots into the transmission and ruins the entire unit. I've very rarely heard of these trannys being able to be slightly repaired. People usually are looking at a rebuild or a remanned unit.
Hiwell I already replaced the fluid and filter (all clean). also the car won't shift no matter the RPM or how fast i depress the accelerator, but it will shift up after I'm off the throttle and the RPM drops , so iam not sur if the problem would relate to fluid pressure. Also it gets better after fully warmed.Does any one know what happens when the torque converter turbine sensor goes?I hope that I have better luck than you have had 90Q45blue, 2 blown tranny's. it doesn't give me much to look forward to
My experience with the turbine sensor is that they leak, but still work. Their location makes for an expensive repair, that's all. Your shifting problem sounds to me as if it might be related to blocked passages in the control body. Dirt or worn parts can block a fine passage and interfere with the shifting. If they agree with this diagnosis, a trans shop may be able to remove and clean the control unit. Level 10 will do this if you ship the control unit to them. But you will probably find most shops won't touch the trans internals- they will want to sell you a remanned unit.
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Q451990
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The turbine sensor will show a code on the dash (TRANSMISSION MALFUNCTION) but I didn't notice any substantial driveability issues with it during the malfunction. The message ususally went away a few seconds after start-up though. If your test showed "OK" then I'd say it's safe to rule out the turbine sensor.
A lot can be told about the transmission's health by noting the time it takes for the fluid exchange and line pressure during the exchange. If you had a true fluid exchange (not just a pan drop) and a new filter installed - it's probably time for a new transmission.
I'd also have someone with Consult (probably your dealer) check it out to make sure the TPS and TCU are working properly. If you see that everything is calling for a shift, but it's not shifting, it's probably leaking seals and a pressure problem. Your transmission's life at 145K is very good if that's the OEM unit, especially if it hasn't been babied with Mobil 1 ATF, an external cooler, etc.
Heath
A lot can be told about the transmission's health by noting the time it takes for the fluid exchange and line pressure during the exchange. If you had a true fluid exchange (not just a pan drop) and a new filter installed - it's probably time for a new transmission.
I'd also have someone with Consult (probably your dealer) check it out to make sure the TPS and TCU are working properly. If you see that everything is calling for a shift, but it's not shifting, it's probably leaking seals and a pressure problem. Your transmission's life at 145K is very good if that's the OEM unit, especially if it hasn't been babied with Mobil 1 ATF, an external cooler, etc.
Heath
thanks again for all of your inputs.unfortunately from you experiences it is sounding like I may need a new tranny,, I am also worried about spending money on it for the internals to go soon. Furthermore it also started to go into neutral in between shifts when backing off the accelarator 
I do have another question, does anyone know if I can put in a 93-96 tranny in my 90 Q45 (I can get one from Japan), was it also set up to start in second gear and are the TCU's compatible...If not does anyone know where I can get a good deal on a remanufactured unit ?The car is just too nice to get ride of.
I do have another question, does anyone know if I can put in a 93-96 tranny in my 90 Q45 (I can get one from Japan), was it also set up to start in second gear and are the TCU's compatible...If not does anyone know where I can get a good deal on a remanufactured unit ?The car is just too nice to get ride of.thanks Fred and Q45 tech.I tried a search as Fred suggested but could not find anything relating to sources for well priced remanufactured tranny's. Can anyone give me some references ?Finally do you think putting in a used 93 tranny is a reasonable risk (from a reputable source, but I can't confirm the car it came off since they are from Japan) and way to minimize spending or do they have enough problems that I should avoid the whole idea of a used tranny ? 
Lastly, what are reasonable prices for these tranny's and the labor ? my local dealership in san francisco wants $2500 for the tranny and about another $1000 for labor, unfortunately they don't seem very good and tend to overcharge on many thingsI will try to get this done within a week or so and will update you with the outcome.All feedback is appreciated 
Lastly, what are reasonable prices for these tranny's and the labor ? my local dealership in san francisco wants $2500 for the tranny and about another $1000 for labor, unfortunately they don't seem very good and tend to overcharge on many thingsI will try to get this done within a week or so and will update you with the outcome.All feedback is appreciated A factory reman Q45 tranny from infitni of Scottsdale or Infinti of Lisle internet parts sales is a discounted $1750 plus shipping/core for NICO members.
Ask for Joe at:http://infinitipartsusa.com/Default2.asp
Ask for Tom at:http://www.theinfinitisupersto...isle/
In both cases its generally better to call than email either.
With shipping and local (non dealer) install you can have it for a granbd less than going directly to your local dealer.
Warranty will be harder to enforce with this method but many find that well worth the risk (what are the chances tranny will bust in first 12,000 miles?not too hi I think).
Fred...
Ask for Joe at:http://infinitipartsusa.com/Default2.asp
Ask for Tom at:http://www.theinfinitisupersto...isle/
In both cases its generally better to call than email either.
With shipping and local (non dealer) install you can have it for a granbd less than going directly to your local dealer.
Warranty will be harder to enforce with this method but many find that well worth the risk (what are the chances tranny will bust in first 12,000 miles?not too hi I think).
Fred...
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