Low throttle issue

B1Ad3

New Member
Hey guys,

When im below 2% throttle the car holds back and hesitates for some reason.

If i press on the accelerator and hold it below 2% you can feel it go but as soon as i get around 2% and or on it, the car holds back and then jerks forward, a bit like im only just starting to press on the accelerator, after that its fine.

Its only when the car is moving not free reving and only happens when the car is hot.

I realise that when the car is on cold idle you need to push down a bit more and all of that.

Any help would be appreciated,

Cheers
 

B1Ad3

New Member
Cars is basically stock with a front mount.

Det sensor and AFM have shown up in the error codes from the ecu.
 
Last edited:

B1Ad3

New Member
If the afm is not doing its job will the det sensor fault come up?

Is it just a matter of getting a multimeter and seeing if its getitng power and a signal?
 

neil240z

Member
help is here.

your diagnosis on your ECU is spot on, the poor running of you car at low rpm will be related to a faulty MAF, pulsarboby will have one or 10! at a good price, or Mr GTiR as i think he recently swapped to a Z32, if your car is holding back when warm then you will require a det sensor, the MAF is very easy to fit though the det sensor is NOT! dont bother taking your car anywhere, you will be wasting money.
get yourself another MAF (AFM) and fit it yourself and see how it runs.

if the det sensor is causing problems still then that wil be next on the menu.

regards

Neil
 

B1Ad3

New Member
Cheers for the reply neil.

I played around with the wiriing all the way to the firewall to check for cuts or any of the wires have been cut, which they have not.

The conector of the AFM looks fine and the connector is around the right way.

When the connected if plugged in i get DET sensor, CRank angle sensor and AFM codes come up, however if i leave it unplugged , run the car and then do a fault check i only get the AFM coming up as a code.

The thing that really makes me think its AFM is that it seems to be an intimitent fault, sometimes it will work and othertimes it wont.

I diagnosed all of today and out fo maybe the 10 times i started it, 2 of the times it started and ran fine however after a min of so the car would go back to a rough idle and try and stall.
 

jonny5

New Member
I have a very similar problem although it is only flagging up a troubleshoot 12 error, once in every 12 attempts (approx)

I handed the car into the Calder racing Development to shed more light on this, I will post their findings - I should hear back from them today.

Fingers crossed I get some useful feedback that I can pass on.

Jonny
 
Last edited:
P

pulsarboby

Guest
i reckon its your afm which could be causing it to run lumpy which will then increase knock levels and bring up the det sensor code!
as neil says, try the afm first, disconnect battery for a while (which will erase codes) then see what its like!
then try another code readout
 

jonny5

New Member
haven't heard back yet mate, will post when i have the info to hand - i aint forgotten - think it is prob the AFM as thats the part that has been ordered
 

B1Ad3

New Member
jonny5 said:
haven't heard back yet mate, will post when i have the info to hand - i aint forgotten - think it is prob the AFM as thats the part that has been ordered
No worries mate,

I got someone here that has one so im gonna try and it seem if it fixes my problem also
 

B1Ad3

New Member
WOuld it be a good idea to check that i have 1.5 volts and 12 volts running to the afm?

That way i can make sure its the afm and not wiring or ECU?
 

B1Ad3

New Member
If the AFM ground is not good enough and or not present so to speak will the AFM put up a code?

And seeing the AFM is not working, does the car just run rich?????
 
Last edited:

neil240z

Member
if your car is running rich it is possible that the lambda sensor is faulty, this could also affect the running of your car, when the det sensor fails the car still runs fine but holds back on boost as the ignition timing gets thrown out, it goes great when cold though.

Neil
 

B1Ad3

New Member
Maybe the car will burst into flames and then insurance will kick in and take this pain in the **** car away
 
I

irishjohn

Guest
sounds like a classic throttle position sensor problem..easy way to check is to take a volt meter and find the 5v output to the computer and very slowly press the throttle watching for any voltake drop outs, it should stat at about 0.8v and go up to 4.2 at wot. better still if u have access to a scope it will be easier to check.
 
Top