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RB20DE NEO accelaration/cruising "problem"

Kapr

By Kapr,
in R Series (R30, R31, R32, R33, R34)

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Kapr

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It is factory manual(5 speed)

The lag is "most" noticeable on 4th gear but it can stil "lag" on 3rd or 2nd...but on the 2n/3rd it is really like "milisecond" loss of power but gas pedal reacts normally.

And it not do that all the time...the "loss of power" is only sometimes and the "i dont know what you want me to do" on 4th is happeing often like the just do not react to the gas pedal(it reacts i can feel/hear it but like nothing happens for a moment)

But as i said it i only a cruising problem and when i try to maintain the speed. 
When i drive it "harder" the car behave as it should...



 

Edited by Kapr
joshuaho96 Veteran

joshuaho96

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16 hours ago, Kapr said:

It is factory manual(5 speed)

The lag is "most" noticeable on 4th gear but it can stil "lag" on 3rd or 2nd...but on the 2n/3rd it is really like "milisecond" loss of power but gas pedal reacts normally.

And it not do that all the time...the "loss of power" is only sometimes and the "i dont know what you want me to do" on 4th is happeing often like the just do not react to the gas pedal(it reacts i can feel/hear it but like nothing happens for a moment)

But as i said it i only a cruising problem and when i try to maintain the speed. 
When i drive it "harder" the car behave as it should...



 

You really need a diagnostic cable and logging of core ECU parameters to get to the bottom of this. 

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GoHashiriya Community Regular

GoHashiriya

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Posted

In my experience the MAFs are pretty robust in these, mine is original and with 255k on it. I did re-sodler the joints at one point but that wasn't my issue, it was the CAS. I would even take a punt at getting a used original MAF from yahoo auction if mine was suspected of funny business - there's one right now at about EUR 50. 

You said your coils were splitfire, but how old are they? They will fail just like the OEM ones and many have 100k+ kms on them now. I thought splitfire went out of business a while ago?

The parts GTSBoy mentioned earlier really shouldnt be too expensive. I went ahead and just threw those exact parts at the car for preventative maintenance - OEM coils/plugs/harness, soldered MAF, rebuilt CAS and Walbro - and, touch wood, it's running fine. 

All this stuff won't be so expensive and you should really expect to replace them anyway on a 25yr old car. 

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Kapr Collaborator

Kapr

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Posted (edited)

@joshuaho96 Do we need any "special" software? I know(99%) that the car has no OBDII port and that i have some extension cord to the interface to OBDII
 

@GoHashiriya
Can you send me the link? I do not see that(it is friday so maybe it was sold)
Yeah they were used but i dont know how many km they done but i presume that if some of the coils gone bad the car would run on 1/X cyl less same as the problem with the connector?
As for the parts...yeah coil are old splits...plugs and harness is brand new...MAF is OEM and upon inspection looks good...connector to that too. CAS i rly dont know(can it do that?)

For the info i have.
I took the car to the highway and the symptoms are that most noticeable "lack" of everything on 4th and 5th gear.
When i try accelerate just a little...the car and the engine change sound like it want it to do something but nothing happens...sometimes it start to accelerate but sometimes it does not...when the car changes the sound but it does not accelerate i would describe that sound as...some type of "chooking" or breathing? The sound is differenet and it changes to "normal" accelerating sound soon as the car starts to accelerate...maybe stuck/dirty throttle body?

BUT if i put "pedal to the metal" car behaves normaly and all those "problems" above are nowhere to be found.

IT IS really only when iam trying to maintain the speed or slightly accelerate.

Edited by Kapr
  • 10 months later...

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