Ok.

I took out my ECU over night, put it back in to go to work this morning and now the car hesitates under partial throttle.

No codes, except for code 23 which has been happening for weeks and it's not related. Normally it throws code 23 and runs fine, so I am not leaning towards that as the problem.


I have 2 brand new o2 sensors that were installed with the new header over 3K miles ago.

Please give me some ideas.

 

After you put the ecu you back in, did you let the car idle for a while ?

 

yeah take it out again. put it back in and then let the car warm up. then try it out.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 90blackcrx &raquo;</TD></TR><TR><TD CLASS="quote">After you put the ecu you back in, did you let the car idle for a while ?</TD></TR></TABLE>


Nah, I just popped it back in and let it warm up for maybe 30 seconds then drove to work.

I am thinking I messed up one of the wires, but it's so easy there is just three clips it goes into so I am pretty sure I didn't mess any wires up.

 

i thought you were suppose to take the negative off the battery let it reset for awhile then put it back on and let your car idle for awhile..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by katb16vo &raquo;</TD></TR><TR><TD CLASS="quote">i thought you were suppose to take the negative off the battery let it reset for awhile then put it back on and let your car idle for awhile..</TD></TR></TABLE>

Is that true?

I will try it regardless...

 

yes take ur neg. side off ur battery and let it reset..it should work after that

 

he pulled the whole ECU out. It's completely reset. No real need to remove the neg cable.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4drEF &raquo;</TD></TR><TR><TD CLASS="quote">he pulled the whole ECU out. It's completely reset. No real need to remove the neg cable.</TD></TR></TABLE>

Yeah, I removed the entire ECU overnight and put it back in this morning.

****, I thought that was the solution. :frustrated:

 

Its known as fuzzy logic, not really used by honda but its the same idea. You have lots of stored memory in your computer.....KAM(keep alive memory) is reset when you unplug it for reset your ecu, your computer has to relearn its open/closed loop and fuel trim/demands again if you do this..........

You have short term fuel trim and long term.....theres alot more that goes into that, but thas the idea.

Same thing happens somtimes if you unplug your battery for a LONG time or its dead and you get a new one or jump it then your car might run like ****. Just reset your ecu pulling the fuse under the battery junction box(the one under the hood) and then go from there, let the car idle until its warmed up.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Kasper-EF8 &raquo;</TD></TR><TR><TD CLASS="quote">Its known as fuzzy logic, not really used by honda but its the same idea. You have lots of stored memory in your computer.....KAM(keep alive memory) is reset when you unplug it for reset your ecu, your computer has to relearn its open/closed loop and fuel trim/demands again if you do this..........

You have short term fuel trim and long term.....theres alot more that goes into that, but thas the idea.

Same thing happens somtimes if you unplug your battery for a LONG time or its dead and you get a new one or jump it then your car might run like ****. Just reset your ecu pulling the fuse under the battery junction box(the one under the hood) and then go from there, let the car idle until its warmed up.</TD></TR></TABLE>


What fuse is it? If you can tell me exactly what fuse it is it would be very helpful.

I don't want to pull the wrong fuse and mess it up worse

Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybrid honda &raquo;</TD></TR><TR><TD CLASS="quote">


What fuse is it? If you can tell me exactly what fuse it is it would be very helpful.

I don't want to pull the wrong fuse and mess it up worse

Thanks</TD></TR></TABLE>

Look at the fuse block in your engine bay. Find the fuse on the diagram that says ECU. Pull it for a minute, then put it back in.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Kasper-EF8 &raquo;</TD></TR><TR><TD CLASS="quote">Its known as fuzzy logic, not really used by honda but its the same idea. You have lots of stored memory in your computer.....KAM(keep alive memory) is reset when you unplug it for reset your ecu, your computer has to relearn its open/closed loop and fuel trim/demands again if you do this..........

You have short term fuel trim and long term.....theres alot more that goes into that, but thas the idea.</TD></TR></TABLE>

Ah, very well put.

 

I took the fuse out last night and put it back in. All was good for about 5 minutes, as soon as I went into VTEC then let off it would bog really bad under partial throttle.

Under WOT in VTEC it's fine, BUT as soon as I let off and drive normal again it bogs, and I mean really bad.

I wll continue to drive and hopefully it will correct itself.

 

reset the ecu again and then let it ilde when you first start it up again for 20 mins...

 

heres what I do...

warm up the car completely...(fan turns on)
turn the car off..
reset ECU (Hazard Fuse 30 sec)
start car with out touching the gas and let it idle for 10 min..

drive happy

 

sounds like you need a tune-up
try some new plugs
new wires
change oil
check your timing
check your timing belt

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by daidilus &raquo;</TD></TR><TR><TD CLASS="quote">sounds like you need a tune-up
try some new plugs
new wires
change oil
check your timing
check your timing belt</TD></TR></TABLE>


Everything is fine, this a motor swap that was done last summer and all the kinks are worked out. The whole ignition system is new from the dizzy to the spark plugs.


But it is still hesitating under partial throttle, it is relly starting to **** me off. I have tried everything suggested and it is still doing it.

I think my ECU is fucked up.

I am getting my ECU reprogrammed next week anyway, but I wanted to hit up E-town this saturday, but it doesn't look like I will be going if the car is still hesitating.

 

i don't know if this will help you but my car did the same thing after i let it sit all winter with no battery but my car does not idle very well so i can do the other suggestings. so i kept trying to get my car to run better and it did after a tank or two but it did trash a set of plugs i think i might have had some water in the tank too but don't know for sure but a set of ngk's is only like 5 bucks i would try that before u hang up the car for the weekend

 

All figured out!

One of the screws that holds the dizzy cap on came off and the cap was loose. I put in a new bolt and now it's as good as new