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Rb25det Wont Rev Past 4500

mr-r33

By mr-r33,
in Engines & Forced Induction

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mr-r33 Proficient

mr-r33

Posted
  • Author
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Interesting Intake piping....

When was the last ttime you changed the plugs?

still building it just wating for the intercool to finish off the Intake

i have not done the plugs on it but had them out and they seem to look ok...mybe do them tomorrow

any particular brand??? NGK platium plugs cost a bit or toyota have platium plugs for $6 a plug wich would be the same as the NGKs

Johny Bravo Proficient

Johny Bravo

Posted
Posted

I had a simular problem with my rb30. At first we thought it was the dizzy and rotor button but turned out to be the crank angle sensor. However mine was not doing it all of the time. Hopefully this helps you and doesn't send you on a wild goose chase like i had.

blk94r33 Mentor

blk94r33

Posted
Posted
the cas is part of the dizzy on rb30es

And they suck to diagnose without a decent graphing multimeter. Lol.

Would you describe it as in in-consistent miss, or a proper limiter? Does it do it worse under load,and does engine temp affect anything? And is the engine stock-standard minus the conversion bit or has it been modified?

mr-r33 Proficient

mr-r33

Posted
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And they suck to diagnose without a decent graphing multimeter. Lol.

Would you describe it as in in-consistent miss, or a proper limiter? Does it do it worse under load,and does engine temp affect anything? And is the engine stock-standard minus the conversion bit or has it been modified?

engine is stock dose it hot dont know about cold as i dont push it hard when cold

engine revs fine like normal untill 4-4500 under load with no load it will rev freely past 4-4500

Trozzle Grand Master

Trozzle

Posted
Posted

Yeah, I'm leaning towards coils and/or plugs. Keep in mind guys if this engine is stock, might have something to do with 4500rpm being the point it bumps the boost up to 7psi. While this is hardly high boost, if the plugs or coils are on their way out it might be enough to cause breakdown in the spark.

blk94r33 Mentor

blk94r33

Posted
Posted
Yeah, I'm leaning towards coils and/or plugs. Keep in mind guys if this engine is stock, might have something to do with 4500rpm being the point it bumps the boost up to 7psi. While this is hardly high boost, if the plugs or coils are on their way out it might be enough to cause breakdown in the spark.

That's what I was thinking with the hot/cold question, as coils that are starting to fail will play up alot more than once they get hot. It revs fine with no load? I'd be saying most likely an ignition problem, otherwise it could be a fuel problem (was it diesel before and did you flush the tank properly? Pressure problem? Blocked injectors?)

Have you checked the plugs and tried gapping them down to the .7-.8 range to see if it improves at all?

  • 3 weeks later...
mr-r33 Proficient

mr-r33

Posted
  • Author
Posted
That's what I was thinking with the hot/cold question, as coils that are starting to fail will play up alot more than once they get hot. It revs fine with no load? I'd be saying most likely an ignition problem, otherwise it could be a fuel problem (was it diesel before and did you flush the tank properly? Pressure problem? Blocked injectors?)

Have you checked the plugs and tried gapping them down to the .7-.8 range to see if it improves at all?

ok guys i have put new plugs in and still nothing but i think it dose it hot or could and somethimes it dose not do it but 99% of the time it dose

no was not diesel befor was petrol

here is a vid of it sorry about the s**t video but you can make out what it is doing

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