Rep Power: 119

It does not, it has a bolt in the hole the pressure sensor would normally screw into. You could take that bolt out and screw a pressure switch in if you want to though, the hole is threaded for it. Then you would need to run a wire from the pressure switch to the appropriate pin on the ECU and it should be happy.

 
Rep Power: 0

ahh that makes sense on my current problem then.
i gave up on that jdm ecu. Put the us ex ecu back in but still can’t get over 4000 rpm and get a vtec code.
I have a jdm harness but I think I saw the wire in the main harness for the oil pressure sensor but I can’t recall if I saw a plug in the engine bay.

you think that would resolve my issue?

 
Rep Power: 0

o and the hole you are referring to is on the vtec solenoid?

 
Rep Power: 119

It should. The US ECU just wants to see a signal from the pressure switch. If it doesn't see a signal, it goes into limp mode and does what yours is doing.

 
Rep Power: 119

Yes it is. There is a 12MM bolt in the hole where the pressure switch would normally go to plug it off. The pressure switch is that rusty thing with the grey plug sticking out the side of the solenoid by the bottom of it. Does that make sense?

 
Rep Power: 0

yup makes perfect sense.

just ordered the vvt oil pressure sensor and a pigtail In case my harness doesn’t have the plug. Going to see if that fixes my issue.


i don’t know if I asked you this. But currently I have the lx exhaust and 02 sensors in.

I have the ex exhaust and 02 sensors.

i saw a forum posting somewhere in here how they handled the 2nd 02 sensor under the car because ex apparently have the connection on another harness.

do you know what I’m talking about?

did you do this as well?

I might even just leave the lx exhaust on and try to run the ex 02 sensors that way 🤷🏻‍♂️

 
Rep Power: 119

You can leave the LX exhaust on and screw the EX o2 sensors into the stock LX manifold, it will run fine that way. However, if you leave the stock exhaust on, you will be giving away some power and fuel efficiency since the LX exhaust is undersized for the stronger VTEC engine, as well as because the stock LX manifold has a catalytic converter in it rather than in the downpipe like the EX exhaust does. I don't have any numbers, but I know that when I replaced my stock LX exhaust with an ebay Spec D Tuning EX exhaust, the difference in power was very noticeable.

As for the downstream o2 sensor wiring, sorry but I can't help you with that. I installed the upstream o2 sensor since that's what tells the ECU how much fuel it needs to add or take away to make it run as well as possible, but honestly I didn't bother with the downstream o2 sensor since all it does is tell the ECU whether the catalytic converter is working or not. It has no effect on air fuel ratios, efficiency, or performance, I just get an engine light and wouldn't be able to pass an inspection this way. Tennessee doesn't have inspections though, so I don't care.

Something else interesting I noticed is that I can actually trick my JDM ECU into not setting a P0141 code by simply connecting a test light to power and the ECU's pin to activate the heater circuit. The test light flashes and it surprisingly will not set a code for the missing downstream o2 sensor as long as it detects a functional heater circuit, it doesn't need to actually see data from the sensor. I don't know if that's just because it's JDM or if a US ECU would respond the same way, just something I find interesting. I may wire up the heater circuit for the downstream o2 sensor in the future when I have time to mess with it so it doesn't set a code though.

 
Rep Power: 0

I got now a jdm transmission in a 05 lx manufacturer in Canada I believe and I get engine light on and rpm are higher than normal at high speed, 70mph about 3050rpm or so and 80mph like 3500rpm. I feel really bad about this as my biggest concern is fuel economy and now is wasting more I believe. I feel frustrated with this rpm thing I just want it to go lower than it normally was before

 
Rep Power: 223

I think the JDM trans is a 3 speed vs a 4 speed or something like that

 
Rep Power: 119

Perfectly normal, the JDM transmission is just geared differently. The engine light is just on because the US ECU sees the higher cruising RPM as a problem since it's not what it expects.
As for lower MPG, I had the same concern but I didn't notice any drop with my setup, probably because I live in a hilly area and it climbs the hills better with this gearing. I still can get up to 38 MPG highway, about the same as the US trans. The EX 5 speed is geared for around 3500 RPM at 70 and 4000 RPM at 80 IIRC and still gets good MPG.

I actually prefer this gearing now that I am used to it. It has better acceleration when flooring it both off the line and when moving (important to me), it has more power and climbs hills better when cruising, the exhaust drone is more tolerable (a rumble instead of a deep roar), the trans will run cooler in traffic since the lower gearing won't work the torque converter as hard, and my MPG hasn't dropped. What's the downside?

Here are the ratios. Green is is JDM SLXA and blue is LX BMXA

 
Rep Power: 0

Wow, glad to know that nice description with graphs. I just did notice faster acceleration which might be better for city driving I guess, don't know about highway since higher rpm if they will consume more or not, on highway I normally drive 70mph so wonder now. The mechanic who got the transmission installed supposedly fill it and all and showed me but it was shifting terrible and second day when I look the stick didn't mark any fluid, I had to add 1 quart and a half extra and now 2 , 3 gear shift so smooth barely noticed, 4th gear is like a little rough still. I think the mechanic put some autozone cheap trans fluid in it , I thought he was going to add OEM fluid but no, I did buy idemitsu z1 quart at auto part

 
Rep Power: 119

Your mechanic should have checked the fluid after test driving it and topped it off if necessary. You checked the transmission fluid with the engine off, right?

The fluid must be designed for Honda transmissions, anything else may cause problems. If you don't know what he used I would replace the fluid with a fluid that is designed for Honda's. I use Valvoline's full synthetic import ATF (blue bottle) and it works great. It's less expensive than OEM fluid and it's synthetic.

What exactly do you mean that 4th gear is rough? The 3-4 shift will be felt slightly more than the other shifts because it occurs with the torque converter locked, therefore there is no dampening effect provided by the converter during that shift.

 
Rep Power: 0

Yes, thanks for that info. I started using valvoline red bottle from Walmart on my old damage transmission not sure if it was correct one now but it said z1. The mechanic supposedly told me he put stp brand from autozone, I was trusting he would use OEM fluid or something good but no he put the cheapest one from autozone and left it missing fluid. Now I have worries about many parts down there hoping everything is in place and well adjusted. I didn't had a home or place to do mechanics and didn't had a choice with this. So the valvoline blue bottle one is fully synthetic = dw-1 ? 2th shift so smooth barely noticeable, 3th smooth too, 4th a little harder but still okay I hope. And yes I did check fluid with engine off and also on both times didn't mark nothing since it was missing a quart and a half
theres a confusion with all these fluids, some people talk about castrol transmax import, others valvoline but now theres a blue bottle import one too and others idemitsu being the one making it for Honda? Everyone uses something different and most people say only OEM honda nothing else.

 
Rep Power: 127

Use OEM if possible. If you want to use something else, make sure it says that its intended use is for Honda's. Everyone has their preferences but Honda's always been pretty picky with OEM stuff.

 
Rep Power: 0

Does the transmission have a separate radiator where the fluid passes to cool it? Wondering about those 2 pipes connections. The guy who did this. Front tire is having a sound and the shaft nuts same old ones he didn't even lock it. The first day I heard a loud clunk sound when turning the wheels all the way

at 80mph I heard another weird noise coming from right side or transmission

 
Rep Power: 225

If you paid this mechanic to fix the car then take it back and make them actually fix it.

 
Rep Power: 119

From the factory the fluid just runs through a tube in the bottom of the radiator to cool it off, but a lot of people (myself included) prefer to install a separate cooler instead of using the one in the radiator for more effective cooling. Also, when a transmission fails, it often fills the cooler in the radiator with metal particles, so it should either be flushed or bypassed so the new transmission doesn't get filled with that crap. My preference is to bypass it and install an external cooler to eliminate the chance of contaminating the new transmission and for more effective cooling.

 
Rep Power: 119

Agreed

 
Rep Power: 0

Would've been good if I informed myself a little more before letting someone install it. I guess is too late now since I had been driving it? but im considering the idea of getting a better cooling system. Doing regular fluid change tomorrow to see what happens.

On my damaged transmission I did about 6 to 7 fluid change in the course of a year, once with Honda OEM, the rest valvoline maxlife red bottle from Walmart.
Then one of those rainy water flooded days all went from perfectly normal to making a whining noise after driving all day through water flooded roads. Next day it started having shifting problems then I got kept going into water while delivering food and I believe it was the water that did the damage, hard to know how but it all happened in 2 days that rained so much flooding the streets.
So my suggestion if you see water on the side of the road avoid it completely, these transmissions cannot handle water and they are low to the ground.

Question I have, there is fluid where the axle shaft connects to the transmission? Is it possible the water can get through there also?

 
Rep Power: 223

There's axle seals....

 
Rep Power: 119

Getting a better cooler won't hurt, especially if you live in a hot climate or do things that create a lot of heat such as climbing a lot of hills, sitting in a lot of traffic, loading your car heavily, pushing it hard, etc.

Valvoline Maxlife ATF is good, I know people who uses it in these cars without issue. It is also a synthetic fluid. I have not personally used it in a Honda though, so my reccomendation would be their Import fluid since I used it for over 200K miles with good results.

Water is death for automatic transmissions if not removed immediately and completely, it causes the clutches to fall apart. I have seen transmissions ruined in hours when the cooler in the radiator fails and fills the trans with water and coolant.

Water should not enter through the axle seals unless they are leaking. The only place water should be able to enter through on a properly sealed transmission would be the vent on the top, but it can also get in around the dipstick if it doesn't fit tightly or if the rubber grommet is old and hard, so if your dipstick fits loosely or the rubber seal seems old and hard please replace it ASAP. Ask me how I know about that

 
Rep Power: 0

05 civic lx Canadian version I believe, bought it 0 miles brand new and since first day the dipstick was always unfit loose, I always thought it was supposed to be that way. I replaced it a little too late the day after it got water damaged. Always had a worry about the dipstick whether it was supposed to be that way for breathing or not. Heh, imagine all the dirt and water that got through there in 15 years

 
Rep Power: 119

The dipstick that came with my JDM SLXA trans fits tightly enough to make an airtight seal, but just barely. Before that I added an o ring around my stock dipstick to kelp keep water out to prevent a 2nd incident. Not a perfect solution, but a lot better than nothing. I may see if I can find some type of rubber plug that fits tightly in the dipstick hole and actually seals and keep the dipstick in the trunk for when I need to check the level so I don't have to worry about water getting in it again. Sealing it off completely won't hurt anything, there is a vent on top of the trans.

 
Rep Power: 0

Walmart supertech less costly one specified for honda z-1 and the other honda z-1 & dw-1 and also is not cheap compare to castrol transmax import at $5.xx something. Is it like equivalent to valvoline import blue bottle?

 
Rep Power: 119

I never used either of those fluids and I do not suggest trying it, finding out it doesn't work in your transmission would be a very expensive mistake. I know first hand that standard Dexron fluid doesn't work in these transmissions because I used it for flushing when I got water in my fluid and it caused it to slip and shudder when shifting until I replaced with the correct fluid. Valvoline's Maxlife or Import fluid isn't that much more expensive.