its suppose to be a 99 2000 si ecu, but all the labels have ben taken out and i find myself redlining at 5k. it seems to be a v tech ecu, but i dont think an si. what ecu tops out at 5k? could this ecu be fried? is there anyway i can check to see what ecu is which without the labels?

thanks in advance


Modified by iRIDEdumped at 4:22 PM 4/24/2005

 

It sounds like the ECU is in "limp" mode. Can you pull any CELs?

 

its running on your car no problem? are you throwing any codes? I'm more experienced with k-series engines, so i don't know, but could it be running in limp mode like a k does when somethings wrong?

 

its on about 10lbs of boost and throws code 22 (i thinkthe vtec code), but thats because its on anon v tec d167y. could it be too much boost? it has a homemade boost controller. how exactly can i check if its in limp mode?

is there any ob2b ecu that redline at about 5k? what exactly is a boost spike?


Modified by iRIDEdumped at 7:37 AM 4/24/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iRIDEdumped &raquo;</TD></TR><TR><TD CLASS="quote">its on about 10lbs of boost and throws code 22 (i thinkthe vtec code), but thats because its on anon v tec d167y. could it be too much boost? it has a homemade boost controller. how exactly can i check if its in limp mode?

is there any ob2b ecu that redline at about 5k? what exactly is a boost spike?


Modified by iRIDEdumped at 7:37 AM 4/24/2005</TD></TR></TABLE>

What MAP sensor are you running?

 

stock map on missing link

 

I'm not familiar with missing link, but I think that the stock MAP is limited to only minor boost (~6psi). You may be exceeding its range. Can you lower the boost level easily to test this?

 

i think the missing link just tricks the map to accept boost, but im not sure whats the max boost it allows to trick. thanks ill try setting it at 6psi and see what happens. where should limp mode cut your redline at? does it sound like my car is in limp mode or is the fuel getting cut off?


Modified by iRIDEdumped at 8:07 AM 4/24/2005

 

Pull the top cover of the ECU. The label should also be printed on the plug socket.

Unfortunately if the ECU is fried, no CEL will be stored. That needs to diagnosed with a scan tool.

The limp mode cuts out near 5000RPM if I recall correctly. I would assume this would occur in the same manner as the normal rev limiter.

 

k i lowered the boost to 5 psi and it still cuts off at about 5300 rpm. i put it back to 10psi and still cuts off. i reset the ecu and jumped the codes and all i got was vtec and 2ndary oxy sensor. so now im pretty sure its not an si ecu. what obd2b ecu redlines at 5500?

 

No Honda or Acura OBDIIb ecu redlines at 5300RPM normally. You may need to connect an OBDII scan tool to diagnose this. This can tell you if the ECU is bad.

 

k thanks. im going to drive home real quick and check to see if my stock y7 ecu does the same thing.

 

could it be that its cutting off where v tec is suppose to engage? how do i fix this?

 

According to the following post, the VTEC CEL could be the cause of limp mode.

https://honda-tech.com/zerothread?id=1220841

You may need to wire a dummy VTEC pressure switch to your ECU. You can search for "limp mode" for more results. Unfortunately, these data are not in the Helms.

 

A 99-00 SI ECU (P2T) looks for a knock sensor that the Y7 does not have.

 

how do i wire a dummy vtec pressure switch to the ecu? it doesnt seem like the p2t is looking for the knock sensor, but would it throw a code if it was. only codes are 22 and 65.

or how can i bypass my vtec pressure from the ecu.


Modified by iRIDEdumped at 3:04 PM 4/24/2005

 

why would you want to run a p2t ecu if your running a non vtec single cam

 

Faulty or missing VTEC components will throw a VTEC ECU into limp mode.

 

because this is the only stock ecu i have at the moment that allows my y7 on boost to run well... i guess cuz of the amount of fuel and other programs this ecu tells my motor to run with.

well i searched and it said something about wiring the 2 wires in the ecu together to turn off the cel, but which wires are they? vtec pressure switch pin jumped to??? vtec solenoid pin or to knock sensor pin or to???

 

The ecu is looking for the knock sensor which your y7 doesn't have and is throwing your car in limp mode. Turn off your boost and you will see that your car runs like **** which is what limp mode does to the motor. Get the right ecu for your car and get it tuned if you're gonna run that much of boost.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chowmien &raquo;</TD></TR><TR><TD CLASS="quote">The ecu is looking for the knock sensor which your y7 doesn't have and is throwing your car in limp mode. Turn off your boost and you will see that your car runs like **** which is what limp mode does to the motor. Get the right ecu for your car and get it tuned if you're gonna run that much of boost.</TD></TR></TABLE>

All you need to know right there.

Obviously your car isnt running well at all, let alone with a DOHC VTEC ECU on a SOHC non VTEC car.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by iRIDEdumped &raquo;</TD></TR><TR><TD CLASS="quote">because this is the only stock ecu i have at the moment that allows my y7 on boost to run well... </TD></TR></TABLE>

obviuosly it doesn't

The only honda that relines under 6K I believe is the 92-95 cx, but since the fuel cutoff is kicking in at the point where vtec would activate depending on temp I would say it's that

Your best option would be to find a 94-96 LS ecu - you could probably even trade for it

 

si ecu also looks for a 2 wire iacv which a y7 motor does not have..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by igo4bmx &raquo;</TD></TR><TR><TD CLASS="quote">si ecu also looks for a 2 wire iacv which a y7 motor does not have..
</TD></TR></TABLE>

Another good point there.

 

actually it does. after bypassing the vtec pressure switch the car runs stronger than ever. i've already done the 2 wire iacv fix. and it was a 00 si ecu after all. the only thing that was preventing redline was the vtec ps... just some simple troubleshooting and i didnt need to spend hundreds of dollars. motor runs strong boosting 10psi and redlining at 8K!


thanks to all the people that helped.


Modified by iRIDEdumped at 4:13 PM 4/24/2005