Savanna rx3 gsii

Hi all, my name is chris and very green to this forum so please forgive me if I am raising a topic that has been flogged to death or steer me in the correct direction

i own an RX7 FD3S 2002 spirit r type c. There where not many of this model as they are automatic. The transmission is sticking in gear when not driven with pedal down to the floor, meaning the gears while driving in traffic does not change (sometimes it does ) unless you remove your foot from accelerator. Also when reversing it seems to bang into gear, the revs are normal 900rpm when doing this.

I want to keep the car stock as it is all factory with zero mods

i suppose my questions are is this a common problem?

is it the solenoids?

does it need a rebuild ?

but my big question what is the rebuild kit code, what make is the gearbox,I have read that they where in Toyota’s and Nissan’s, was this gearbox in any other Mazda’s. Is also have heard there is a wiring loom that is connected to the gearbox that is unique to Mazda.


any help would be great.

thank you chris

mazdaverx713b

iTrader: (91)

First question is, did you ensure your fluid level is correct and does the fluid smell burnt at all?

Savanna rx3 gsii

Hi thank you for reply, I have had the transmission fluid, the filter changed and good quality fluid by a mechanic and it still does it. However he did say it smelt a little burnt when he drained the transmission and the oil coolers

Akagis_white_comet

iTrader: (4)

Is that a RB4A-EL transmission? I want to say Mazda started using the instead of the regular R4A-EL around 1997, but I could be mistaken on the exact date. Anyway, if it's anything like the R4A-EL and Q4A-EL in the Cosmo, it has a specific order of events that happen with each gear change. Basically "release that clutch" "engage this clutch" "unlock torque converter", etc. What gear is it sticking in? If it's like the Cosmo's transmissions, I can narrow it down that way.

Also, did it suddenly start behaving this way or did it gradually inch toward this outcome? Adaptive shifting was starting to become common (my daily 1997 Ford Expedition has it), so this might be a factor.

Savanna rx3 gsii

Hi Akagis, thank you for your reply

This what i am trying to establish if it is the RB4A or the R4A, like i said there are some gears boxes shared across other makes. There is one thing i read that said that Mazda took the gear box and added some electronics to it but in australia mazda do not have any part numbers for spirit R 2002 models

I think i inherited the problem with the gearbox and yes if you manually shift its fine but it from first to second where the problem is. Would it be solinoids? or rebuild and if its a rebuild what rebuild kit is required?

Not sure if its like the cosmo boxes.

Any help would be greatfull, thank you.

Akagis_white_comet

iTrader: (4)

Please note that I am NOT an expert in automatic transmissions not do I play one on TV. If it can be manually shifted in the manner you've illustrated, this does not sound like a hydraulic issue. So based on that, it is a reasonably safe bet that solenoids and other hydraulic components are fine. Let me re-iterate that it is reasonably safe to think this, but not guaranteed.

This sounds more akin to the Road speed reference/Throttle opening reference information not being what the EC-AT Control Unit is expecting. To make a long story short, there are a bunch of charts in the manual(s) that show at what road speed, throttle opening and other conditions (in Hold mode, in Power mode, etc) that all contribute to the transmission changing gears. My hypothesis is that if it's receiving wrong or garbled information on the input side, it just "nopes out" on the outputs, resulting in refusal to shift as you are experiencing. For reference, transmission error codes on the Cosmo can be read from the Hold indicator flashing after putting it in Self-Diagnosis mode by shorting the TAT Terminal to Ground in the Diagnosis Connector, or one can use the DT-S1000 Diagnostic Computer. I'm not sure how it would be done on a Spirit R yet.

Anyway, I do have all 6 Japanese FD Parts Catalogs if you are looking for something. A chassis number (VIN) would be a big help to ensure anything needed will work as intended. Plus, it would help identify what specific transmission you have. I can't currently determine when the RB4A-EL was introduced, but the FB4A-EL (front wheel drive) was introduced in June 1996 and the RC4A-EL came about in 5/1999. I'll take a look tonight in the Japanese manuals and see if it gives a date for the transmission manual's introduction. One small step and all that

Akagis_white_comet

iTrader: (4)

Please note that I am NOT an expert in automatic transmissions not do I play one on TV. If it can be manually shifted in the manner you've illustrated, this does not sound like a hydraulic issue. So based on that, it is a reasonably safe bet that solenoids and other hydraulic components are fine. Let me re-iterate that it is reasonably safe to think this, but not guaranteed.

This sounds more akin to the Road speed reference/Throttle opening reference information not being what the EC-AT Control Unit is expecting. To make a long story short, there are a bunch of charts in the manual(s) that show at what road speed, throttle opening and other conditions (in Hold mode, in Power mode, etc) that all contribute to the transmission changing gears. My hypothesis is that if it's receiving wrong or garbled information on the input side, it just "nopes out" on the outputs, resulting in refusal to shift as you are experiencing. For reference, transmission error codes on the Cosmo can be read from the Hold indicator flashing after putting it in Self-Diagnosis mode by shorting the TAT Terminal to Ground in the Diagnosis Connector, or one can use the DT-S1000 Diagnostic Computer. I'm not sure how it would be done on a Spirit R yet.

Anyway, I do have all 6 Japanese FD Parts Catalogs if you are looking for something. A chassis number (VIN) would be a big help to ensure anything needed will work as intended. Plus, it would help identify what specific transmission you have. I can't currently determine when the RB4A-EL was introduced, but the FB4A-EL (front wheel drive) was introduced in June 1996 and the RC4A-EL came about in 5/1999. I'll take a look tonight in the Japanese manuals and see if it gives a date for the transmission manual's introduction. One small step and all that

Clumsy Ninja Edit: Just checked the WM-4053-8 Supplement (August 2001) and it shows the RB4A-EL listed in Section K: Automatic Transmission, while listing the R4A-EL Manual (WM-122, May 1990) under "Related Resources". The September 2000 Supplement (WM-4050-7) shows the same, as does the December 1998 and December 1995 Supplements. Based on this, I'm going to say that the RB4A-EL is a slightly revised R4A-EL, introduced for Series 7 and 8, but the fundamental maintenance and operation are the same. Might be awhile before I can REALLY dig into it properly, but I can send you a few pages from my copy once I get my new scanner.

Savanna rx3 gsii

Thank you Akagis. Makes sense what you are saying. I will get the vin number and PM you

once again thank you for taking the time to look into this. Champion

Akagis_white_comet

iTrader: (4)

So I dug into the FD Workshop Manual (WM-4002-1, from 11/1991) and into the Transmission section. What I found is that there are 2 ways to read Service Codes. One is with the DT-S1000, the other is with a combination of two SST (Special Service Tools). Those two are the DISC Monitor (49-H018-9A0, from the HB Cosmo/Luce) and System Selector (49-B019-9A0, I believe from the BF 323/Familia).

Overall, using the DT-S1000 despite it being in Japanese is the simpler method. I translated most of the on-screen text earlier this year when tackling the procedure for the Eunos Cosmo, so I know how the system behaves. Anyway, from a quick glance, the Service Code numbers and descriptions looks the same as the Cosmo. I'll keep an eye out for one and the associated 5.25" System Disk, it's not the first time I've had to get unobtanium out of Japan, probably won't be the last either.

Savanna rx3 gsii

wow thank you, not sure how some of you guys are so knowledgeable, amazing work. Let me know how you go i will send the VIN number to you

thanks again

Akagis_white_comet

iTrader: (4)

"Wanting to learn" is where it all begins. That factor alone will take you quite far with any project. The rest is a matter of knowing what you're looking for, asking the right questions to the right people, and some happy little accidents along the way to help you find what way you want to go. Plus there's a wealth of knowledge here as you've found out. Not to toot my own horn, but my 20B conversion led me to wanting to understand how the 20B's twin turbos worked. Found the vacuum diagram by accident, then had a friend at work help me translate it back in 2012. That led me to wanting to know more about how the Cosmo worked. A few more happy accidents later, and I'm about to finish writing a full workshop manual for the Cosmo, having taught myself Japanese from scratch.

Moral of the story: That "Side Quest" can change everything, and all of this started because of a guy that watched Initial D in 2006 and got a car from it for $1400 on craigslist...

On a related note, I did find a complete DT-S1000 Set in Japan tonight but it's just over $5000. A bit steep for me right now, so I dug a bit further, came full-circle to the 3rd Gen section where someone built a suitable substitute running from a Laptop sometime around 2010. So it CAN be done.

Savanna rx3 gsii

Haha you seem to be a patient smart man, I looked at a wiring diagram and threw it in the bin haha

so 20B twin turbo. That must be scary to drive.

Thank you once again.

Akagis_white_comet

iTrader: (4)

I have a sneaking suspicion that your Throttle Position Sensor is the issue here. To make a long story short, there are two signal wires (Narrow and Full Range). One of them also is an input into the EC-AT Control Unit for the transmission. If the voltage on this pin is too LOW, it won't shift down based on throttle position (EC-AT thinks you're James May and just cruising along) when it should. If the voltage is too HIGH, the EC-AT will keep it in the present gear for maximum rev power (EC-AT thinks you're Jeremy Clarkson and going "POWAAAA").

Anyway, I got your email and have the 12/98 Wiring Diagram book open right now. ECU Pin 3I is from the TPS, and is shared with the EC-AT Control Unit. It's the Black/Green Wire. Narrow Range TPS signal is usually a bit of a smaller range (about 1.0-4.4v) compared to the Full Range wire (typically 0.5-4.9v give or take) and the EC-AT control Unit is looking for voltage to be over a certain point (let's say 3.5v for this example) to trigger Jeremy Clarkson mode. Otherwise, it defaults to James May driving mode. These voltage numbers are probably NOT accurate, and are just to illustrate how the system behaves. I'll look in my other FD books to see if I can find the correct figures.


EDIT: 5 minutes after posting this, I have the correct info for the TPS, found in the ECU Pinout chart for Series 7. Same thing applies to Series 8:

ECU Pin 3I (3-Igloo) (Full Range, goes to EC-AT too):
Black/Green Wire
Fully Closed: 0.1~0.7v
Fully Open: 4.2~4.6v
Range: 0.4~4.3v, nice and smooth increase from fully closed to fully open

ECU Pin 3K (Narrow Range):
Green/Red Wire
Fully Closed: 0.75~1.25v
Fully Open: 4.8~5.0v
Range: 1.0~5.0v nice and smooth increase from fully closed to fully open

ECU Pin 3A (Voltage Reference for all sensors)
Brown/White Wire
Approx. 5.0v constantly

ECU Pin 3AB (Sensor Ground)
Brown/Black Wire
Ground wire for TPS, MAP, Oil Metering Pump Position Sensor, Igniters and Air/Coolant/Fuel Temperature Sensors
This is basically a Pass-through to the ECU Ground Pins (1AF, 1AJ, 1X and 1AB) and goes put to Ground #11 (Ring Terminal) underneath the Upper Intake Manifold near the Oil Filter. According to the Connector Finder page, it's straight down from the TPS connector (B1-39)

So, unplug the TPS, feed it 5v on the Brown/White wire pin, Ground on Brown/Black, and see how the Black/Green and Green/Red wires' voltages behave when you open the throttle by hand. If there are any dead spots or jumps in voltage on either signal wires' pins, it's the TPS making the car behave goofy.

Akagis_white_comet

iTrader: (4)

Sent your Build Sheet. Also, if you do need a new TPS, N3A2-18-911 is the correct one and found on any automatic FD. According to Atkins Rotary, it is discontinued but they believe the manual version (N3A1-18-911) works in its place. Voltage figures are the same for both at the ECU, so I see no reason it wouldn't work all the same.

Savanna rx3 gsii

Thank you so much. I will order one in and try that, beats removing a transmission.

let you know how I go

Akagis_white_comet

iTrader: (4)

Before you buy anything, test your current TPS as prescribed above. A FD TPS seems to have gone up quite a bit in price as of recently, so testing your current one using a USB power supply (they're 5v too) makes perfect sense here. If you don't already have one, I'd suggest getting an ATX computer power supply and modifying it as I did here.

I took it a bit further than most do, by having two pairs of Banana jack posts. Bottom pair is 5v, top pair is 12v with a built-in voltmeter/ammeter. Both the 12v and 5v can output 10A, which is more than enough for testing almost anything on the bench. It's actually the second one I've made, the one before it decided to short the 12v post against the metal case (Ground) a few years ago. Hence the plastic panel on this one, plus the ammeter.

It was the finishing touch for this. I outgrew my old Craftsman tool box and was completely unhappy with what could be purchased due to their poor usage of space on one or more levels for a $600+ pricetag. So I designed and built my own from scratch for around $350, with specs most would consider overkill at every turn. Twelve drawers, each 18.5" front to back by 22" wide (by 2.5", 4.5" and 8" deep respectively), with a total of just over 20,000 cubic inches of storage space, weight capacity just over half a ton, and a modular design that's easily moved by one person with no help, plus a nice big 24x56 work surface on top. And most important of all, one drawer just for diagnostic tools like cables for Forscan, INPA and PA-Soft (BMW), a couple bluetooth OBD2 scanners and even an AK90+ key programmer.

Every surface gap is sealed to prevent fluid intrusion, both on the shells and in the drawers and I tested it by standing on top of it. And we can't forget the metal flake blue finish and some slick handles made from Aluminum C-channel and bolted on to pull from the back of each drawer face at 3 points (4 for bottom drawers). Simply put, the entire drawer would have to self-destruct before the handles could either bend or come off.


The right tool for the job always makes any job a LOT easier.

Redbul

iTrader: (26)

I had heard that automatic transmission were not that hard to find, because generally an automatic FD was less desireable, and would be used for donor parts cars. Maybe you want to search out a used one. You might be surprised to find them lying around.

I have one in fact. 69,000 origiinal KM out of a 1992 Type X.

Ask Marcus Read and go from there.