I recently had my gearbox reconditioned and a new clutch installed and have had a problem since getting the car back. It's a bit hard to explain so bear with me. I am having different issues with different gears in my mk1 (gen 1) 3 MPS (UK).

Problem 1 is when changing from 3rd to 4th. If I am accelerating with say 50% throttle, when I press the clutch to go into 4th the car all of a sudden jerks forward for a split second before it stops accelerating. I did a log to capture this and it shows that whilst accelerator position goes from 50% to 0%, throttle position goes from 50% to 70% and then to 0%. It happens really fast and doesn't do it every time. Only does this from 3rd to 4th.

Problem 2 is that in 5th gear my throttle is a lot more sensitive than in all others. It takes much less pedal input to get the car to go fast. It feels like 100% throttle at only 50% pedal input. All other gears feel normal.

The car was working perfectly fine before it had the box reconditioned and the clutch replaced. It had the 2nd gear, hub and synchro replaced. I have removed Justin's map and re-applied it, but it made no change. It must be something to do with the work they carried out but they are adamant that it isn't. Also they thrashed the car whilst they had it, not sure if that makes a difference. Do you have any idea what the problem could be? I'm at a complete loss.

Thanks.

If they thrashed your car while they had it and you have the logs to prove it then I would bring that up to them. If they still do nothing for you then I would make it very clear that you will seek legal assistance and reporting them to the Better Business Bureau. Usually at that point they will be more then willing to help you. As far as the issue Im not sure the K04 is small so it does spool rather quickly. If I put my foot into it in 5th in my 2013 MS3 it will do the same thing. If anyone else has something to ad or advice there are two sets of ears here listening.

How do you know they "thrashed" your car? Did they admit it? Was it an actual shop? Who does that? And you didn't go back and demand they fix it? Grow a set and go back in there and tell them to fix it.

If you have an AP take some logs so you can see what's going on.

I have the dash acm footage. This matter has already been settled with the garage. All I want to do is try and work out why my car is now behaving differently now the work has been carried out. They have already said that they don't know why, but if I can prove it was due to the work they carried out then they will pay to get it fixed.

I explained what is happening on the logs in my original post. There seems to be and accelerator pedal position and a throttle position. These are not matching when the problem occurres. I thought this could be a sensor, but it only happens in certain gears.

This isn't anything to do with the size of the turbo, it's that in 5th gear the 2 sensors are not matching and the car thinks I am inputting more pedal than I actually am.

Depending on what tune you're running, the Accelerator Pedal Position and Throttle Position will not have a linear relationship. Moreover, the Throttle Position maxes out at ~76%, while your Accelerator Pedal Position maxes out at 99%.

Post datalogs of the problems happening, then maybe we can do more than guess wildly.

So I've uninstalled the Cobb all together and the issue is still there, so it can't be related to the tune. 5th gear still pulls like a mother compared to all the others with just a small amount of input.

:facepalm2:

What?

You can use the AP to datalog. The datalogs will help us determine if there is, in fact, a problem with the way the sensors are relating to one another, or if there is a physical problem of some sort.

post a log, is what

youve got wood, lol

No cruise in 5th. Help?
 

Hey guys,

I have a 2008 mk1 Mazda 3 MPS (UK) and I recently had a new clutch fitted and also had my transmission refurbished (2nd gear syncro).

Since having the car back the cruise no longer works in 5th gear. Also, whilst in 5th I get WOT on any more than about 30% pedal input. So in the other 5 gears if I use 30% pedal I get 30% acceleration. In 5th if I use 30% pedal input I get 100% acceleration.

I got no engine lights, no fault codes, the speedo works and I do not suffer either of these issues in any other gear.

Car is stock engine wise.

Any help would be great. Thanks.

Do you have any means to take a datalog? If so, please post one of the 30% input issue you're describing.

I don't, but I do remember when I took logs that the accelerator pedal position and throttle position columns did not match up. Whilst the former read about 30% the latter read about 90%

I have uninstalled the Cobb from my car some time ago now.

sounds like a gear selector sensor or speed sensor issue in the transmission for it to only happen in 5th, I would say something went wrong with the rebuild if thats the only change you made especially if there is no cobb or tune on the car

Is there such a thing as a gear selector sensor? When I spoke to Mazda on the phone they said the only sensors relating to the cruise are clutch, brake and speed sensors. If the speed sensor was fucked then surely cruise wouldn't work in any gear?

However if what you say is true, then the car could maybe be thinking it's in neutral?

Don't take what im saying as gospil, I am spit balling. I have never heard of such an issue and you just had the trans swapped or rebuilt. Maybe you got a different trans that has an electrical issue or something else is wrong with it.

just usually you look back to your most recent changes to find problems and the tranny was just messed with.

there is the other chance that its not related and your having ECU issues. Check the FSM for troubleshooting steps for cruise control.

I'm very confused. How do you know those values if you don't have a way to log? It sounds to me like you may have multiple issues here, at least one of which may be tune-related.

i guess his foot tells him how much he's pushing the pedal. very fancy.

So you've had these problems for a while? Because you state values when you logged, but that you uninstalled the cobb a while ago.

What mods? Stock engine wise means stock engine. I agree with Vansquish that it seems like it's a tune problem. 5th gear APP translation table might need to be looked at.

I already kind of addressed this in my first post as he said there is no AP on the car which implied to me there is no tune and therefore the tune should be fine. If there was a tune that's the first thing I would check is the Pedal tables.

possibly take it to the dealer and ask them to reflash it, should be free

In his other thread from back in June, that he abandoned ( http://www.mazdaspeedforums.org/foru...roblem-202810/ ), he states that he was tuned by Justin and has an AP. In an effort to see if the problem stemmed from the tune he supposedly unmarried the AP from the car and there was no change in how 5th gear was acting up.

That thread ended with everyone asking for logs...

Unless he's since sold the AP, he should reinstall and post logs...

@EliotG;

https://31.media.tumblr.com/3f6b1ca3...JIo1r7fnmm.jpg

Thanks guys. I still have my Cobb V2. I'll reinstall it and take some logs. I'd forgotten about the other thread to be honest, but I'll stick with this one.

I'll update when I have logs.

I had the problem with the tune, removed the tune, tried a different tune and uninstalled the Cobb. Still had the problem.

Could they have perhaps used some parts from a mk2? Causing the ECU to loose it's shit?

Thanks again

well both threads are now merged

Right, here we go. I can't open these on this crappy laptop so have no idea what they show, but interestingly when I reinstalled the Cobb I got 3 error codes:

U0100
U0101
U1900

Engine management light was not illuminated.

For the logs I believe the first two are 3rd through 6th gear and the last is 3rd through 5th.

- datalog 13 doesn't show the alleged weird correlation between pedal position and throttle position;

- datalog 14 doesn't show the alleged weird correlation between pedal position and throttle position; and...

- datalog 15 doesn't show the alleged weird correlation between pedal position and throttle position.

So...um...I'm not sure what you're complaining about.

U0100: ECU communication
U0101: TCM communication
U1900: ABS communication

Sounds like you either connected or disconnected a diagnostic device from the vehicle's OBDII port while the key was in the "ON" position.

Butt dyno ain't right.

I'm on another PC look at the boost levels. Producing no more than 3 PSI in gear 3,4 and 6. Gear 5 it spikes in excess of 12psi.

The last log does show the difference. First two gears the values match. In 5th there is over 10% difference.

Do you have an invoice with the parts they replaced?

No. I don't know 100% what they replaced. They jerked me around a lot and I've requested that they send me a full parts list. I wouldn't be surprised if they 'lost it' though.

As far as I am aware it was just the 2nd gear, hub, synchro, seals and bearings.

Did you have a 2nd Gen transmission put in the car?

You were interested in doing so in one of your other threads...

They were supposed to replace my gearbox. Instead they rebuilt my existing one. So as far as I am aware it is my original gearbox.

I have edited the logs to show where the problem is and re-uploaded.

Log 1: Orange is 5th gear, blue is 6th.

Line 56 (5th gear)
Pedal position = 30.81%
Throttle position 39.39%
Boost = 10.75 psi

Line 70 (6th gear)
Pedal position = 29.25%
Throttle position 29.25%
Boost = 0.85 psi

In 5th over 4.3 seconds I gained almost 17mph. In 6th gear over 4.75 seconds I gained 3mph.


Log 2: Blue is 4th gear, orange is 5th.

Line 30 (4th gear)
Pedal position = 32.76%
Throttle position 30.03%
Boost = 3.65 psi

Line 45 (5th gear)
Pedal position = 31.20%
Throttle position 37.83%
Boost = 11.04 psi

In 4th over 4.02 seconds I gained <3mph. In 5th over 4.28 seconds I gained 13mph.


Log 3: Blue is 4th gear, orange is 5th.

Line 25 (4th gear)
Pedal position = 30.42%
Throttle position 29.65%
Boost = 3.94 psi

Line 42 (5th gear)
Pedal position = 30.03%
Throttle position 37.05%
Boost = 12.90 psi

In 4th over over 2.83 seconds I gained 8mph. In 5th over 3.34 seconds I gained 11mph.

Interesting, but not quite the 30%-70% correlation you were suggesting earlier. That said, have you contacted your tuner?

Maybe not, but that's what it feels like given the boost pressure. There is clearly something going on.

Yes. Justin said that he didn't know why the car was doing it and that there was nothing in the map that would cause it. Especially as I have now removed it too.

Even Mazda said they don't know what to do, and that scanning it for codes won't come up with anything. What the fuck am I supposed to do? :(

Take it back to the shit shop that "fixed" your transmission and tell them they need to make it right.

You paid for a shop to service your tranny, and they cant tell you what they did or provide an invoice? And you have a dash cam showing them beating on the car?

If it were me, I would have my lawyer contact them. This seems like a huge mess..

UPDATE

Car taken to Mazda. They did a diagnostics and found that the car believes it is in neutral when the gear lever is in the 5th position. They reckon that the gearbox place has either damaged or not installed the neutral/drive switch properly.

I have emailed the gearbox garage and am awaiting a response. To fix the switch the gearbox needs to be removed.

Above in red is incorrect. I believe the mechanic thinks the issue is on the other side of the switch, see my next post.

I'm not sure why they would have to remove the transmission to replace that switch.

Refer to the thread linked below to get an idea of what and where we are talking about. Step #3 in the thread shows the switches specifically.


http://www.mazdaspeedforums.org/foru...cement-191891/

Hmm. Interesting. Are these fairly easy to replace? I might have a go myself as you can access those from under the car...

I guess he thinks the problem is on the other side of the switch. The switch itself is obviously working as there are no codes and it works in all the other gears. His exact description was "Neutral/Drive switch not functioning in 5th gear. Possible detent gear change rod issue. All other gears ok".

EDIT:

PROBLEM SOLVED

I went out today and removed the neutral switch from the car. Checked that it wasn't stuck (which it wasn't) and re-installed it. Problem gone. All gears now work perfectly fine. I can only assume that they had over tightened the switch because it was a complete ball ache getting it out.

Those never come out easy. Glad you got things sorted out.