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Did you get your driver side axle seated?
Nope, That's one of the few things I need to button up tomorrow. Couldn't drive the car tonight anyways, somehow I misplaced two fuses (or they never existed...) so my headlights don't currently work.

Did idle the car for a bit and noticed the AFR is super lean (like >22:1 lean, saw as high as 32:1). I don't recall checking it in the past since I was more concerned with other stuff. Suspect there's a wiring issue. The sensor voltage decreases and eventually levels out at 0.00, so maybe something is wired backwards... I haven't detected any knock, so I kinda doubt it's actually running that lean.

Tried replying last night but it isn't showing up for some reason... lets see if this does.
 
Nope, That's one of the few things I need to button up tomorrow. Couldn't drive the car tonight anyways, somehow I misplaced two fuses (or they never existed...) so my headlights don't currently work.

Did idle the car for a bit and noticed the AFR is super lean (like >22:1 lean, saw as high as 32:1). I don't recall checking it in the past since I was more concerned with other stuff. Suspect there's a wiring issue. The sensor voltage decreases and eventually levels out at 0.00, so maybe something is wired backwards... I haven't detected any knock, so I kinda doubt it's actually running that lean.

Tried replying last night but it isn't showing up for some reason... lets see if this does.
The pins for your primary O2 sensor are likely wired backwards in your adapter harness. Trace all four O2 wires. I would highly suggest tracing all the wiring in your adapter harness and verifying it against Hondata's schematic and the RSX service manual. I discovered a lot of wiring mistakes in mine.

Also read post #9 below. The primary O2 heater circuit must be on its own switched relay. If you power it through the pgm-fi or ign relays it will cause a residual backflow of current through the ecu and keep the pgm-fi relay latched closed with key off. If you key on and off, then disconnect the batt and hear a relay click, that is likely the pgm-fi relay which staying latched closed.
 
Nope, That's one of the few things I need to button up tomorrow. Couldn't drive the car tonight anyways, somehow I misplaced two fuses (or they never existed...) so my headlights don't currently work.

Did idle the car for a bit and noticed the AFR is super lean (like >22:1 lean, saw as high as 32:1). I don't recall checking it in the past since I was more concerned with other stuff. Suspect there's a wiring issue. The sensor voltage decreases and eventually levels out at 0.00, so maybe something is wired backwards... I haven't detected any knock, so I kinda doubt it's actually running that lean.

Tried replying last night but it isn't showing up for some reason... lets see if this does.
idle is not a high enough load to cause knock even very lean
 
The pins for your primary O2 sensor are likely wired backwards in your adapter harness. Trace all four O2 wires. I would highly suggest tracing all the wiring in your adapter harness and verifying it against Hondata's schematic and the RSX service manual. I discovered a lot of wiring mistakes in mine.

Also read post #9 below. The primary O2 heater circuit must be on its own switched relay. If you power it through the pgm-fi or ign relays it will cause a residual backflow of current through the ecu and keep the pgm-fi relay latched closed with key off. If you key on and off, then disconnect the batt and hear a relay click, that is likely the pgm-fi relay which staying latched closed.
yes, I spent a lot of time fixing the heater circuit on my car!
 
The pins for your primary O2 sensor are likely wired backwards in your adapter harness. Trace all four O2 wires. I would highly suggest tracing all the wiring in your adapter harness and verifying it against Hondata's schematic and the RSX service manual. I discovered a lot of wiring mistakes in mine.

Also read post #9 below. The primary O2 heater circuit must be on its own switched relay. If you power it through the pgm-fi or ign relays it will cause a residual backflow of current through the ecu and keep the pgm-fi relay latched closed with key off. If you key on and off, then disconnect the batt and hear a relay click, that is likely the pgm-fi relay which staying latched closed.
The swap harness I received included a relay that is connected the same as the AF Sensor relay is depicted in the shop manual, so I think I'm good on that front (unless this relay is staying latched and I need another relay...). I'll double check that it doesn't stay powered in a bit.
 
The O2 sensor wires were backwards, sensor is now working correctly. As far as I can tell the heater circuit isn't staying powered, I'll keep an eye on it though just to be sure. May just install a cutoff switch, which would make this a nonissue.
 
Car drove briefly today, wasn't far, but it did move under it's own power, which is a massive improvement. It's been stumbling a bit on cold starts, however once it idles for a bit it's perfectly fine. It's some kind of fueling issue, engine is pretty lean for around 5s after it starts monitoring, but settles down to normal pretty quick. Wondering if it's an IACV issue, but I really don't want to mess with that given how hard it is to access. Could always be a tuning thing I guess, but it does it with both of the base tunes that are suitable for the car, and otherwise seems perfectly fine after that initial couple of seconds. Seems to run fine otherwise, definitely not quiet inside the car though. Pretty sure it's louder inside the car than outside.

On an unrelated note, passenger window no longer works for some reason. Found this out when I went to roll it up because of rain.
 
Does anyone have a good K24A2 base tune? I'm not sure that I trust the hondata basemaps (was seeing more knock than I'd like when driving last), and the local tuner doesn't have openings until September. Still 100% planning to get it tuned professionally, but I have a track day scheduled before I'm going to be able to get it done by an actual tuning shop.
 
I don’t have a base map for you, however you might be able to find some good info from the KMiata community since they like to use the K24A2 as well. Anyway, hope this helps and good luck at the track!!
No worries! I ended up getting it tuned at a turner a bit further away (also got some help from the K20a forums). Made 199whp, the car should have come with this engine from the factory. Really need to see about getting a different intake though, it just runs out of air above 6k.

Unfortunately I'm getting really bad grind in second, every other gear is fine, but second does not feel like it engages until the very end of the throw. Could this be a linkage issue? I suspect it's synchros, but really don't want to drop the engine out again....

I also had an issue where I couldn't find a gear when trying to go out of 4th, clutch did disengagae and I could find N, but I couldn't find 3rd or 5th (admittedly I did not try 2nd....) It went away once I stopped and moved the linkage by hand and didn't happen again though, so I've not had any luck tracing down the issue.
 
I don’t have a base map for you, however you might be able to find some good info from the KMiata community since they like to use the K24A2 as well. Anyway, hope this helps and good luck at the track!!
No worries! I ended up getting it tuned at a turner a bit further away (also got some help from the K20a forums). Made 199whp, the car should have come with this engine from the factory. Really need to see about getting a different intake though, it just runs out of air above 6k.

Unfortunately I'm getting really bad grind in second, every other gear is fine, but second does not feel like it engages until the very end of the throw. Could this be a linkage issue? I suspect it's synchros, but really don't want to drop the engine out again....

I also had an issue where I couldn't find a gear when trying to go out of 4th, clutch did disengagae and I could find N, but I couldn't find 3rd or 5th (admittedly I did not try 2nd....) It went away once I stopped and moved the linkage by hand and didn't happen again though, so I've not had any luck tracing down the issue.
 
Did you drive the tranny before installing it? Could be synchros or incorrectly adjusted linkage. Also, don't use Honda tranny fluid. 2nd gear grind is factory standard issue. If you didn't install a clutch type diff then switch to Amsoil Synchromesh. It will take care of any grinding caused by fluid.

The RBB intake stalls above 6-6500 rpm because its plenum volume is only 1.7L. The plenum has to be equal to or larger than the displacement of the engine.

I have a modded RBB intake with an additional chamber welded on that increased the plenum to 2.5L. It still makes RBB torque but now makes power to 8500.

I made a 2nd one, so this one is available. It was tested on a k20a2 so I trimmed off the water passage. Ktuned sells a water bypass adapter if you are interested in this manifold. PM me.

You do not want a k20 manifold. You lose the torqur from the RBB, and the good ones make power above 7500. I've tested them - PRB, RSP, RBC (RRC is overhyped. See RSP).

You don't want to spin a stock k24 to 8500. You can calculate piston speeds vs k20.
 
Did you drive the tranny before installing it? Could be synchros or incorrectly adjusted linkage. Also, don't use Honda tranny fluid. 2nd gear grind is factory standard issue. If you didn't install a clutch type diff then switch to Amsoil Synchromesh. It will take care of any grinding caused by fluid.

The RBB intake stalls above 6-6500 rpm because its plenum volume is only 1.7L. The plenum has to be equal to or larger than the displacement of the engine.

I have a modded RBB intake with an additional chamber welded on that increased the plenum to 2.5L. It still makes RBB torque but now makes power to 8500.

I made a 2nd one, so this one is available. It was tested on a k20a2 so I trimmed off the water passage. Ktuned sells a water bypass adapter if you are interested in this manifold. PM me.

You do not want a k20 manifold. You lose the torqur from the RBB, and the good ones make power above 7500. I've tested them - PRB, RSP, RBC (RRC is overhyped. See RSP).

You don't want to spin a stock k24 to 8500. You can calculate piston speeds vs k20.
Have any pictures of the modded RBB? I'd love to see what was done to it.
 
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