p28 wont rev after 3k

[junior_tm]

my ecu is chipped and does not rev past 3k? anyone know why this happens?

[Homer Simpson]

its in limp mode.

trying not to kill itself.

Are you throwing any codes?

[Barefoot]

:goodjob::goodjob:
its in limp mode.

trying not to kill itself.

Are you throwing any codes?

[Tech5]

Sounds like you have a problem my friend!

[junior_tm]

i have 02 sensor

[FRYLOCK]

Sounds like you have a problem my friend!
nah really u think:doh:

[Tech5]

;) ;) ;) ;)
nah really u think:doh:

[AnthonyF]

MAF sensor TYPICALLY..not always.

-Ant.

[G.C]

Did it happen right after you swapped out your ecu?

[NoWAyItZTOMmY]

did timing jump?

[EmminoDaGreat]

MAF sensor TYPICALLY..not always.

-Ant.


Good luck finding a maf.

[xdavidscenex]

MAF sensor TYPICALLY..not always.

-Ant.

honda with p28 and....MAF? :thinking:

[EmminoDaGreat]

Check the chip, make sure it has not come out of the socket, make sure you haven't put it in backwards, make sure someone didn't scramble it w/ the static electricity shock... Make sure all the cells are done...

[AnthonyF]

Good luck finding a maf.

Hey, I was just suggesting something. I don't know code names like that. lol.

-Ant.

[SiRed94]

IACV plugged in?

[James777]

Is chipping the ecu the only thing that has changed since the problem has developed?

[scttydb411]

1. check codes
2. if not codes more than likely speed sensor and launch control (you have an old version of crome that doesn't have throttle position as an option for launch...just speed and rev).

speed sensor can go bad w/o throwing a code (ie: still puts out acceptable voltage to ecu to not trip cel, but not any speed to ecu). therefore, the ecu thinks it's not moving and results in only reving to the pre-determined launch rev.

always check codes first...that almost always steers you towards the fix.

[Homer Simpson]

we cannot help you if you don't reply to any of our post

all you said was o2 sensor

[Christopherr]

Is your car running poorly even though it won't rev past 3000 rpms?

Any misfires?

Since a P28 is OBD1, is your check engine light on? If it is, do you know how to pin it to flash the light for DTCs?

Also, P28s has VTEC a switch, what type of engine do you have?

General question to assist you finding your issue(s).

Usually, when you cannot rev past a specfic RPM with a drive-by-cable, you're ECU is either retarding spark or fuel delivery...in essence, as Homer stated, keeping from killing itself.

I'd start with a fuel pressure test...if pressure is dropping at 3000 rpms, something is telling it to do that.

[junior_tm]

sorry i didnt answer some question i work night shift...well im going to check with the guy that has the ecu and i'll bring some more info tomorrow


thanks to everyone

[RBS]

so is your IACV plugged in? lol

[HatchHero]

most likely map sensor..what engine harness are u using? is everything plugged into the right spot??

[James777]

is it map and iat that the plugs are interchangeable on some hondas? or was it tps?

[scttydb411]

is it map and iat that the plugs are interchangeable on some hondas? or was it tps?

map and tps.

iat gets mixed up with a variety of 2 wire sensors:
pwr steering
iacv
iab (burns ecu)
ect (hard stretch, but i've seen it)

[Tech5]

Yeah I have to because either everyone is a Mechanic so they say or everything thinks they know everything about a Honda/acura lol:lmfao: :lmfao:
map and tps.

iat gets mixed up with a variety of 2 wire sensors:
pwr steering
iacv
iab (burns ecu)
ect (hard stretch, but i've seen it)

[Code-Aye]

this just happened to me.its your tps

[SiRed94]

map and tps.

iat gets mixed up with a variety of 2 wire sensors:
pwr steering
iacv
iab (burns ecu)
ect (hard stretch, but i've seen it)

My favorite is when I get a car that has multiple ones switched up and multiple check engine lights and the customer tells me they have switched out the IACV, MAP, IAT, etc. and they still have the same problem. :lmfao:

Or when they tell you "I think I have bent valves because my car is skipping but, I'm getting spark on all cylinders." and then they have plug wires swapped up. :lmfao:

I swear, I could write a 30 page thread on all the dumb shit I have seen over the years.

[Atlblkz06]

TPS sounds like a good bet to me. If the MAP was messed up it wouldnt "stonewall" at 3k. But hey its just a wild guess. Let us know what it was when you do get it fixed!

[SandM]

haha, as already stated. my old p28 with crome did it too.... damn speed sensor went bad and i had constant launch control

[LeX]

I had this issue with a different type of car but i thought of all the stuff you guys mentioned.

Turned out the ECU was getting 10v instead of 12v and that was causing the issue. See how much power your ECU is getting lol!

[NOCLUE]

Bump for help

[junior_tm]

well the guy never called me back so i don know but thanks to everyone that tried to help i spread some love(reps) to yall