SOLVED tach drops to 0 after ~4800 rpm car revs past it fine
what WB are u using?
it appears like u have the narrowband signal going to the ELD instead of WB.
or maybe u have an adjustable slope WB like the LC-1 or similar & u have to go into the WB software & set the WB output & slope to whatever u want or 0-5V,10-20AF like u have above.
if this is the case then check the narrowband output is set to 0-1V inverted switch at 14.7AF
it appears like u have the narrowband signal going to the ELD instead of WB.
or maybe u have an adjustable slope WB like the LC-1 or similar & u have to go into the WB software & set the WB output & slope to whatever u want or 0-5V,10-20AF like u have above.
if this is the case then check the narrowband output is set to 0-1V inverted switch at 14.7AF
innovate lm-1
actually, everythings working now except for a small problem ill have to research into. Dont ask.. I have no idea why.
Went home, cut the two resistors, re uploaded the stock map with absolutely no modifications. Turned on. Crazy high AFR like before, but then 18.... 17.... 16.. 15.. 14.7. Oddly enough it took 20 seconds before it did that. The engine was warm, so maybe its just messed when cold. Regardless, went for a spin and it felt fine. AFR was still showing as 10:1 in hondata. I went and did the same thing as before, set wideband to ELD 10, then uploaded. EXCEPT this time I shut down the car, turned on, uploaded, shut down, then started the car and it worked fine.
Wideband is also showing correct AFR as my gauge (slight offset compared to controller but MUCH closer).
Only problem I noticed, the tach goes to zero once it hits 5000 or so. Second it drops back below 5000 it works again. I was reading honda tech and apparently its happened with other people and obd2b cars.
actually, everythings working now except for a small problem ill have to research into. Dont ask.. I have no idea why.
Went home, cut the two resistors, re uploaded the stock map with absolutely no modifications. Turned on. Crazy high AFR like before, but then 18.... 17.... 16.. 15.. 14.7. Oddly enough it took 20 seconds before it did that. The engine was warm, so maybe its just messed when cold. Regardless, went for a spin and it felt fine. AFR was still showing as 10:1 in hondata. I went and did the same thing as before, set wideband to ELD 10, then uploaded. EXCEPT this time I shut down the car, turned on, uploaded, shut down, then started the car and it worked fine.
Wideband is also showing correct AFR as my gauge (slight offset compared to controller but MUCH closer).
Only problem I noticed, the tach goes to zero once it hits 5000 or so. Second it drops back below 5000 it works again. I was reading honda tech and apparently its happened with other people and obd2b cars.
Tested yet again, works fine in stock ecu, hondata only goes up to 5k. I dont think its a map issue, I've datalogged and it logs the RPM fine past 5k, MAP looks fine. This seems to be a common problem with Obd2b to obd1 conversions.
http://www.honda-tech.com/showthread.php?t=2621310
My only two other problems right now:
1. the car runs FINE, even when cold. I found out this weekend that the red LED = BAD. Ive had this before and thought it was normal because it always seemed to have done this. When I had it running fine last week it must have suddenly wanted to work right. Well yesterday I swapped in my s300 again, and it ran like crap with CEL on. I was driving and the rpm was constantly up and down, afr was off. I sat there thinking what the hell it was, then went to grab my cable for datalogging. I didnt even touch the usb server side port hard, just a simple simple light touch and all of a sudden CEL off, rpm goes down to normal, red light switches to green.
I thought maybe it wasnt grounded right, as it wasnt mounted in the stock ecu spot, but now im thinking the s300 module isnt seated all too right.
The second problem is, the mounting. The darn thing is 40% longer than the obd2b ecu. some connectors are so close to the floor it would barely fit, secondly the wiring doesnt seem to be long enough. .. gr.
Any advice would be appreciated.
http://www.honda-tech.com/showthread.php?t=2621310
http://honda-tech.com/showthread.php?p=39937682tach works but at 6k it pegs to zero
Ive searched and foudn that obd2 b gets its tach signal from the ecu.
i found it weird that the tach works,but only til a certain rpm.
So I also found that i need to put a wire from the empty spot on the dizzy to the shock tower
however no one specified where on the shock tower.
I found plenty more before but cant find them right now. I'm just posting this up for others conveniences if they also have this problem.Can you take a pic of how you wired in your resistor for me please? I also put a 1k resister on A21 and A25 and my now tach moves but not past 1500. I
My only two other problems right now:
1. the car runs FINE, even when cold. I found out this weekend that the red LED = BAD. Ive had this before and thought it was normal because it always seemed to have done this. When I had it running fine last week it must have suddenly wanted to work right. Well yesterday I swapped in my s300 again, and it ran like crap with CEL on. I was driving and the rpm was constantly up and down, afr was off. I sat there thinking what the hell it was, then went to grab my cable for datalogging. I didnt even touch the usb server side port hard, just a simple simple light touch and all of a sudden CEL off, rpm goes down to normal, red light switches to green.
I thought maybe it wasnt grounded right, as it wasnt mounted in the stock ecu spot, but now im thinking the s300 module isnt seated all too right.
The second problem is, the mounting. The darn thing is 40% longer than the obd2b ecu. some connectors are so close to the floor it would barely fit, secondly the wiring doesnt seem to be long enough. .. gr.
Any advice would be appreciated.
Spunkster: ok I got the thing mounted, it just took some persuasion to get the harness connected. They do have the same mounting points but where the harness connects is very very close to the floor because the whole unit is longer.
I have an s300 obd2b special edition so it must have been purchased from and built by hondata. (edit: this is why I was having trouble mounting it, the unit it so big and then it has a special adapter on the bottom)
It IS throwing a red LED and not a blinking one. However only every now and then. When it does, car runs like crap, CEL goes on. When I tried datalogging that one day when it was red and touching it with a usb cable suddly everything worked, I drove home and noticed that every now and then the car would surge or jerk and the CEL would flicker.
I went out to investigate more yesterday and found that, when connected, if I tap or knock on the ecu a bit it would go red for a split second, and sometimes stay on. I took off the cover and pressed down on the s300 module and hooked everything up again and now it stays green. However I am a bit scared of it working loose again. For now though at least I know its a bad connection.
So now I guess its down to one and half things. the Tach and trying to figure out how the s300 module inside the ecu is installed so I can secure it better.
I have an s300 obd2b special edition so it must have been purchased from and built by hondata. (edit: this is why I was having trouble mounting it, the unit it so big and then it has a special adapter on the bottom)
It IS throwing a red LED and not a blinking one. However only every now and then. When it does, car runs like crap, CEL goes on. When I tried datalogging that one day when it was red and touching it with a usb cable suddly everything worked, I drove home and noticed that every now and then the car would surge or jerk and the CEL would flicker.
I went out to investigate more yesterday and found that, when connected, if I tap or knock on the ecu a bit it would go red for a split second, and sometimes stay on. I took off the cover and pressed down on the s300 module and hooked everything up again and now it stays green. However I am a bit scared of it working loose again. For now though at least I know its a bad connection.
So now I guess its down to one and half things. the Tach and trying to figure out how the s300 module inside the ecu is installed so I can secure it better.
As far as the tach goes (my FINAL problem). Ive searched hours on end and I am still stuck.
I tried bumping up any possible values in the calibration that may be messing up the tach. For example, enable launch control, bump the 4500 up to 9000 then disable it. Also did this for the A/C switch off (default is 5000) and so on. Didn't work.
Took out the emanage (seen in the pictures), even with it out, it did not work past ~5000rpm. Apparently this caused a couple others a similar problem from past searches.
edit:
As I understand obd2b ecu's create RPM signal from other sensors, whereas obd1 the distrib produces the signal. I wonder how its working at all.
I tried bumping up any possible values in the calibration that may be messing up the tach. For example, enable launch control, bump the 4500 up to 9000 then disable it. Also did this for the A/C switch off (default is 5000) and so on. Didn't work.
Took out the emanage (seen in the pictures), even with it out, it did not work past ~5000rpm. Apparently this caused a couple others a similar problem from past searches.
edit:
As I understand obd2b ecu's create RPM signal from other sensors, whereas obd1 the distrib produces the signal. I wonder how its working at all.
my understanding is its only the individual coil pack motors that sought an alternative tacho signal source like the K series.
have a look at your dizzy plug,it will have 2 fat pins in it,is one of them a small blue wire?
if there is then thats your tacho signal off the ignitor in the dizzy.
check how the emanage was receiving an rpm signal & make sure this wire if it was sourced from the same wire as tacho is not connected to anything & well insulated.
btw....u have an emanage piggybacked onto hondata???
why???
have a look at your dizzy plug,it will have 2 fat pins in it,is one of them a small blue wire?
if there is then thats your tacho signal off the ignitor in the dizzy.
check how the emanage was receiving an rpm signal & make sure this wire if it was sourced from the same wire as tacho is not connected to anything & well insulated.
btw....u have an emanage piggybacked onto hondata???
why???
^ I'm only temporarily using emanage until I get tuned.
My dizzy plug (harness?)? fortunately I took pictures of this today (I took the cap off to see if there was a missing pin on the ignitor, there wasnt)
edit: the splice was done by me and not hacked up, I soldered everything and used heatshrink. If it was a wire problem it would have problems with stock ecu (in which RPM works fine past 5k, tested twice).
My dizzy plug (harness?)? fortunately I took pictures of this today (I took the cap off to see if there was a missing pin on the ignitor, there wasnt)
I did this, its simply spliced into ICM (b13 on harness). I disconnected the emanage to rule this out. I'm not sure if it even IS receiving the rpm signal past 5k -- I dont have a datalogging cable (proprietary, not a usb cable).check how the emanage was receiving an rpm signal
edit: the splice was done by me and not hacked up, I soldered everything and used heatshrink. If it was a wire problem it would have problems with stock ecu (in which RPM works fine past 5k, tested twice).
also oddly:
http://honda-tech.com/showthread.php?t=463548
I tried following this persons advice from this old post on HT. However I cant find what hes talking about to wire to on the dizzy. There is no spare terminal.
http://honda-tech.com/showthread.php?t=463548
I tried following this persons advice from this old post on HT. However I cant find what hes talking about to wire to on the dizzy. There is no spare terminal.