i have a B20Z with a p75 ecu. the normal redline or fuel cut off is 6700rpms. a little history, engine has 20k miles. ive never had this problem in the 2 years ive had the engine in the car. the car has been stored since november and has been started about 2-4 times a month to keep things going.
i got the car out this weekend for the start of my autox season, in a spirited drive, the engines fuel is cutting off at 5500rpms??? so ive check the oil levels, i disconnected the battery terminal and i unplugged the ECU for about 3 hours. checked the ecu for corrosion when leaving work.. its still cuts off at 5500.
do any of you have any ideas as to what this problem could be? any help is appreciated! thanxx

EDIT!! Figured out!! read below!


Modified by spock_rocker at 4:10 PM 4/11/2006

 

does it have any other form of rev limiter, such as MSD or a software editor program like turboedit, Uber, chrome, etc? i remember forgetting the revlimit function on turboedit and chasing my tail for days over it once.

how old is the fuel and are you sure its not the ignition breaking up or something to that effect? got a wideband?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike_belben@yahoo.com &raquo;</TD></TR><TR><TD CLASS="quote">
how old is the fuel and are you sure its not the ignition breaking up or something to that effect? got a wideband?</TD></TR></TABLE>

what I would guess, old fuel

 

i was thinking old fuel myself, i just wasn't sure if that would cause the redline to differ 1200rpms... i will put new gas in the car tomorrow and hopefully that will correct it.
oh and no its a stock P75 ecu out of an integra. like i said ive never had this problem before. thanxx again!

 

anyone else?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spock_rocker &raquo;</TD></TR><TR><TD CLASS="quote">i have a B20Z with a p75 ecu. the normal redline or fuel cut off is 6700rpms. a little history, engine has 20k miles. ive never had this problem in the 2 years ive had the engine in the car. the car has been stored since november and has been started about 2-4 times a month to keep things going.
i got the car out this weekend for the start of my autox season, in a spirited drive, the engines fuel is cutting off at 5500rpms??? so ive check the oil levels, i disconnected the battery terminal and i unplugged the ECU for about 3 hours. checked the ecu for corrosion when leaving work.. its still cuts off at 5500.
do any of you have any ideas as to what this problem could be? any help is appreciated! thanxx</TD></TR></TABLE>

Problems like oil level, old fuel, etc. are not going to cause this sort of problem. This sounds like an engine management problem. Are there any codes?

 

thats what i was afraid of.

 

Could his TPS be off some how? I dont see how bad gas is going to lower the stock rev limit? If the TPS was off though does it throw a CEL I cant remember?

 

i havent been getting the check engine light at all..

 

Last summer my VTEC solenoid failed on my '00 Si and the same thing happened. I could not get past 5500 rpm.

I find out that this is a "limp mode" that the ECU puts the car into when it senses a problem. In my case the check engine light came on immediately and I knew there was a problem.

Everything else was OK but it could not rev past 5500. Do some research to see what "limp mode" or "get-home mode" can be triggered by on your particular ECU.

I had never heard of this before on a Honda until it happened to me but my dad's lexus has the same thing.

Good Luck,
Andy

 

no check engine light, everything else is fine, the car idles fine, drives fine.. im just looking into getting a different ECU for now.. hopefully i can find one!!

 

looking for more opinions

 

i was told it could be old oil clogging the filter and its throwing my ECU into safe mode? ill change the oil friday and see if that helps

 

i had the same problem with my civic 92 vei, it redlined at 8200, then i fitted a recon gearbox and about a week later the redline dropped down to 7000, couldn't understand at all. I had various electricians out to try and get the problem sorted but it never got sorted out. Still does it now, just had to cope with the problem... very gutting though

 

yea this isnt really something i want to live with..

 

oil changed today, problem still presists. im having a hard time believing its the ECU cause im not getting a CEL..

 

changed the plugs, fuel pressure is consistant at 39%, changed cap and rotor. reset ECU a million times. it reved up to 6300 this morning, at this afternoon it was at 4600... i dont know what else to do!

 

Im still thinking ECU. Do you have an SAFC or VAFC? If the fuel setting are set improperly it can cause that.

 

nope.. fuel is all stock so to speak

 

Jeremy dont forget to add that you put in your chipped ECU and it still didnt rev up like it was supposed to.

 

i did ad that.. to the orginal post...

this morning when it was in the 40s.. the revlimiter cut in at 6k then this afternoon its 60 degrees it cuts out at 4500

 

the car is at honda.. they cant seem to find anything

 

Thats wack obviously something is wrong if it will not rev to the stock rev limiter of the ecu.

 

but its not reving to the 7400 on the chipped ECU either!?

 

ok.. this is the lamest **** ever!! my tach was off, i drove with the honda mechanic who worked on it. he hooked up a timing light to my battery and one spark cable.. the tach on this timing light red 6900 everytime!