What could the issue be? The stock tachometer works fine with the stock ecu plugged in.
When I plugged in a chipped P06 converted ecu into a 01 Integra R, the tach would not work. The ecu ran my 98 R just fine, so I doubt it is the ecu.
I was working with Crome Pro version 1.2, not the beta versions as they are filled with bugs that I can never seem to get around.

The only thing that I want to add / mention is that even with the stock ecu, at idle, if the check engine light is on it has somewhat of a flicker to it. Could this be related to distributor and causing the tach not to work?

I am at a loss on this one.
Boomslang obd2b to obd1 harness, p06 vtec ecu, crome pro 1.2 using the basemap that "Tomdata" from PGMFI.org made for the Type R. Another strange occurrence is that the IACV slider worked on my car, but not his. Same ROM and everything.

 

Do your self a favor & use hondata, ectune or neptune. As you can see crome isn't all that it is claimed to be. (You get what you pay for).

Concerning your tach issue, there is another thread somewhere about this. You simply need to add a 1k resistor to your conversion harness between A21 and A25.

 

I was tuning someone elses car. I have a s300 for myself and also the Hondata dealer kit with romeditor 4 that are my preferred software.

could you better explain where to wire the resister? I didnt know if you meant 1 resister across those 2 wires, or 1 resister in line of each wire.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MOVE OVER &raquo;</TD></TR><TR><TD CLASS="quote">I was tuning someone elses car. I have a s300 for myself and also the Hondata dealer kit with romeditor 4 that are my preferred software.

could you better explain where to wire the resister? I didnt know if you meant 1 resister across those 2 wires, or 1 resister in line of each wire.</TD></TR></TABLE>

Wire it between the two wires. I.e. |---Resistor---|

 

gotcha. I will do this on the weekend and see if that fixes it.

I will look for it myself, but if you know of the thread that you referred to, link me to it please.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mtber &raquo;</TD></TR><TR><TD CLASS="quote">Do your self a favor & use hondata, ectune or neptune. As you can see crome isn't all that it is claimed to be. (You get what you pay for).

Concerning your tach issue, there is another thread somewhere about this. You simply need to add a 1k resistor to your conversion harness between A21 and A25.</TD></TR></TABLE>

John's probably referring to my thread.... https://honda-tech.com/zerothread?id=2230515


This is probably the fix to your problem.

 

ok, I have to ask, why does shorting ignition power (A25) to the tach signal(A21) through a 1K resistor make the tach work? (it shouldn't, unless the tach input is picking up the alternator or coil noise on the power line, which would be a muddy signal)


the reason why 00-01 tegs have a tach problem when converted to OBD1 is because the OBD2b tegs get their tach signal from the ECU not the distributor like every other honda before 2000.
Running the wire from the distributor is the best move IMO.

BTW: Crome 1.4.9 is stable.
eCtune is better though.

 

I never did reply back here, but jumping it works. I dont understad how either, but it does. My question is why is it not required on all obd2b cars? I have seen several people that have never had to jump those wires and they still had a working tach. would that be due to the conversion harness already being modified??

the car i was working with was a 01 ITR with a boomslang harness. the odd thing is, i know the previous owner and he had a boomslang harness as well at some point. he never had to ru any wires or jump the haness to get his tach working. odd.....

 

When I have more time I'll scope the A25 line just to see what signal the tach input may pick up.
I'll also cut my current tach wire and jumper with the resistor to see if it works...
I'm at a loss as to why it would work.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Relic1 &raquo;</TD></TR><TR><TD CLASS="quote">ok, I have to ask, why does shorting ignition power (A25) to the tach signal(A21) through a 1K resistor make the tach work? (it shouldn't, unless the tach input is picking up the alternator or coil noise on the power line, which would be a muddy signal)


the reason why 00-01 tegs have a tach problem when converted to OBD1 is because the OBD2b tegs get their tach signal from the ECU not the distributor like every other honda before 2000.
Running the wire from the distributor is the best move IMO.
</TD></TR></TABLE>

IDK WHY it works...I just know first-hand that it DOES work. That fix came straight from Boomslang. I was having this SAME problem. I made a thread and none of the knowledgeable tuners on here knew what it was. One of them recommended I call Boomslang, and this was the fix they sent me. Well...I followed it and after soldering the resistor into my harness, the tach worked!

 

It does work. I have tested it on a customer's 00 si :-)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Relic1 &raquo;</TD></TR><TR><TD CLASS="quote">
Running the wire from the distributor is the best move IMO.
</TD></TR></TABLE>

I find it strange that you want to do something like this when 2 people have used the fix that I posted and are telling you IT WORKS. It came from the conversion harness manufacturer. It's a SIMPLE fix....why not just use it?!