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Dodgy airflow meter :o(

marcus

By marcus,
in General Automotive Discussion

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Beer Baron Grand Master

Beer Baron

Posted
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can I suggest that if this 'hiccup' is only happening on cruise (ie. part throttle/light load) then you should look at your O2 sensor. as when running in closed loop your ecu is trying to target a stoich AFR for economy. It does this by reading the value from the 02 sensor, if this sensor is stuffed it won't run right on cruise, but will run fine under full throttle conditions.

Also, as Abo said you cannot use a Z32 with an unmodified ecu. the car may run, but it will run like sh1t.

marcus Contributor

marcus

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can I suggest that if this 'hiccup' is only happening on cruise (ie. part throttle/light load) then you should look at your O2 sensor. as when running in closed loop your ecu is trying to target a stoich AFR for economy. It does this by reading the value from the 02 sensor, if this sensor is stuffed it won't run right on cruise, but will run fine under full throttle conditions.

Also, as Abo said you cannot use a Z32 with an unmodified ecu. the car may run, but it will run like sh1t.

I never though about the O2, will definately try that. What are they worth do you know??? Also heard a rumour that you can use the falcon ef/ el sensors.... How true is this theory???

Maybe drive to melbourne when the vic guys are having ameet of some sort. It only takes a few minutes to swap over a stock ECU or AFM. I'd hate to see spend money on something that doesn't fix your problem.

Also thanks Abo bob Its a good idea to swap and try before buying, just gota find the time to make a trip down.

marcus Contributor

marcus

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I think that is true about the falcon ones.  The information is definitely available somewhere on this forum.  There is a very long thread about o2 sensors so look in there.

Do you know where I can find it here. There is so much info on this site, I wouldn't know where to start???

Anyone confirm the falcon O2 sensor theory???

paulr33 Grand Master

paulr33

Posted
Posted

the o2 sensor wont affect your cars running smoothness or hiccuping

the 02 sensor is used by the ecu to save fuel when the throttle isnt at WOT

so its only used when you dont floor it, the ecu checks this value to lean out the fuel mixture to save fuel. it shouldnt make the car "hiccup". the o2 sensor from the ford falcon works and i have one in my r33, worked with stock ecu and powerfc

the falcon o2 sensor is a generic sensor and its used on a few cars actually.

its just easier to ask your local parts place for a ford au falcon o2 sensor

rather than a skyline one cos then they go what model and what year and they wont have it on your system or give you a o2 sensor that is for the r31 skyline as their computers/database usually only have the r31 as it was aussie delivered

that being said i dont think the o2 sensor is causing your problem. you can unplug it to test that theory if you like, it will just run mega rich and waste fuel. the plug is on the dump pipe just after the turbo heat shield. its a little prong thing that goes into the exhaust pipe. the plug with have 3 wires, just disconnect it

marcus Contributor

marcus

Posted
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the o2 sensor wont affect your cars running smoothness or hiccuping

the 02 sensor is used by the ecu to save fuel when the throttle isnt at WOT

so its only used when you dont floor it, the ecu checks this value to lean out the fuel mixture to save fuel. it shouldnt make the car "hiccup". the o2 sensor from the ford falcon works and i have one in my r33, worked with stock ecu and powerfc

the falcon o2 sensor is a generic sensor and its used on a few cars actually.

its just easier to ask your local parts place for a ford au falcon o2 sensor

rather than a skyline one cos then they go what model and what year and they wont have it on your system or give you a o2 sensor that is for the r31 skyline as their computers/database usually only have the r31 as it was aussie delivered

 

that being said i dont think the o2 sensor is causing your problem. you can unplug it to test that theory if you like, it will just run mega rich and waste fuel. the plug is on the dump pipe just after the turbo heat shield. its a little prong thing that goes into the exhaust pipe. the plug with have 3 wires, just disconnect it

So you don't think its the O2 sensor then???

The car only hiccups on cruise (ie; hardly pushing down on the accelerator or when you start to back off) sometimes it may do it when you slow down to a stop without braking...

The mixtures on the dyno appeared fine (4 runs). Could that just be luck, afm, o2 sensor, ecu or what???

sav man Grand Master

sav man

Posted
Posted

When i drive my car in the morning, it plays up (like the AFM is unplugged), but when i drive it home 6 hours later it's fine. My auto electrision told me my ecu isn't in the best health (it wouldn't let my AC turn on), so would the morning driving be my ECU or AFM? Are R33 and R32 AFM swapible?

marcus Contributor

marcus

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hi marcus,

 

did you sort anything out after our phone convo? let us know how you go

Hey Paul,

Cheers for all your help. I am waiting on a stock BOV to try (in terms of the bov noise) and am waiting on the O2 sensor also to come in.

Will keep you posted on how it goes...

Marcus

paulr33 Grand Master

paulr33

Posted
Posted

no probs, i noticed (when i was looking for stock afms) you were inquiring about a z32 afm, the z32 wont work with the stock ecu unless its been remapped or you have an safc (not sure if you knew or not)

marcus Contributor

marcus

Posted
  • Author
Posted
no probs, i noticed (when i was looking for stock afms) you were inquiring about a z32 afm, the z32 wont work with the stock ecu unless its been remapped or you have an safc (not sure if you knew or not)

Cheers, but yea the boys told me the same thing earlier. However after our discussion I don't think its afm... Will find out when I try the o2 i guess...

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