acceleration problem

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jl83's picture
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jl
qc

Jul 22, 2012
acceleration problem

so ive search on the forum and the web and found nothing about the problem

 

little description:my engine wont go over 3500 rpm under load or normal acceleration on each gear cold or hot temp, low trottle or full ,,on neutral i can push trottle and it rev flawlessly over 5000 rpm,, im really confused!!!and my plug are really brown,,im cathless and dark smoke come out of the exhaust

 

so i changed all gasket(manifold,turbo,dp) ive tinked it was my issue the manifold gasket was dead(leak) but nothing..changed the sparkplug and nada...i want some experienced info

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London Ontario

Dec 23, 2009

your ecu is in limp mode, check your sensors, MAF TPS O2 etc

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Really Noneyourbuis
Canada

May 11, 2008

Look on here about using a consult cable or the ECU bulb flash test

Mine isn't bigger than yours.. I just like to drive

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jl
qc

Jul 22, 2012

ZED_not_zee wrote:

 

Look on here about using a consult cable or the ECU bulb flash test

 

so ive looked for the sensor just before the cath,,i unpluged it and nothing my car still cut at 2500-2800 rpm,cleaning the blow off valve same thing again...so what kind of code reader i have to get for the error code or where i can get the ecu bulb flash test??

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Ryan
Winnipeg, MB

Mar 21, 2008
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samuel buckler
mississauga

Oct 26, 2012

same problem. i had a hacked up wire harness fro a piggy back fic. the wire for the maf sensor came loose. so make sure that your maf sensor is working.

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samuel buckler
mississauga

Oct 26, 2012

some one please help this man out with this problem. i have the same problem and its very depressing :(

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B.C. Canada

Mar 31, 2009

jl83,

 

From what you've given us it sounds like it's running rich and like Linx said is in limp mode. you have to check the sensor readings to see if they are all reading within spec at the ecu so you can determine if it's a bad sensor which is throwing the ECU into limp mode.

For example the TPS sensor should read approximately 0.5v at full close to a nice sweep of regular increasing voltage to approximately 4.5V at wide open throttle. If the voltage drops out at all during the throttle opening which increases the voltage then the TPS sensor is no good and can cause faults which could lead to a Limp mode to save the motor.

 

Limp mode runs the motor rich so you don't blow the motor running lean and also limits the revs to stay in a safe zone but still runs so you can "limp home" the vehicle.

 

The car can rev in neutral to higher RPM's since it has no load and requires significantly less fuel to do so and the MAF,TPS,RPM and CTS are all part of the load calculation for the ECU so it knows when the motor is under load.

Check all your motor sensors which can effect your load calculation at the ECU to determine where your problem is coming from. In short "As Linx said before"

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John p
newmarket ontario

Aug 23, 2010

check the maf !!!!!!

1992 nissan pulsar gti-r Black sold/1993 red/rusty parts car /1990 nissan pulsar gtir fully built vet with to much jam

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Luke Lebouthillier
Montreal

Oct 2, 2012

looks like a MAF problem. Reground the maf

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samuel buckler
mississauga

Oct 26, 2012

ok. and does any body know where i can stick the paper clip so i can read the bulb and see what codes i get. also i have a maf for a 300zx is there any way of wiring that up to the stock ecu?