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Discussion Starter · #1 ·
Alright so I’ve been driving my car around and realized that my car won’t rev pass 4K rpm , I’ve heard about limp mode and it causing cars to not rev past a certain number but the thing is idk why it’s doing that what could possibly cause limp mode on da car anyone got any ideas maybe ? K20a2 swapped eg all stock except a lil 3in HR CAI with kpro (pnd ecu)
 

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4k rev limit is typical for cases like missing VTP signal or if it happens while driving, but is restored after restart oil pressure drop hitting VTEC. If the TPS signal is missing, it won’t rev high either.
All easy to check logging into the ECU and checking error codes and plausibility of sensor signals. Or post a data log here and we’ll have a look.
 

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Discussion Starter · #4 ·
4k rev limit is typical for cases like missing VTP signal or if it happens while driving, but is restored after restart oil pressure drop hitting VTEC. If the TPS signal is missing, it won’t rev high either.
All easy to check logging into the ECU and checking error codes and plausibility of sensor signals. Or post a data log here and we’ll have a look.
Shall I data log while driving ???
 

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1st obersrvation MIL light is on. Would you mind posting the codes the ECU threw?
2nd: Idle is way high at 1300+rpm at 0% TPS. This is commonly caused by fiddling with a throttle stop screw, poor quality = leaking aftermarket throttle bodies or classically a stuck IACV. Or there may be an other air leak in the intake path.
3rd: Your VTEC window is set to 540mbar and 2200 rpm. At the same time VTP sensor is enabled. Thing is that at 2200 rpm oil pressure is insufficient to engage VTEC and the sensor has not triggered yet. -> MIL. Over time this can lead to cam journal wear.
4th, your cam angle maps make no sense whatsoever, especially the high cam. 5° VTC from 4000 rpm?? This would work if you use a straw as an exhaust pipe.
5th why is there a 7 deg ignition timing jump from 4700 rpm to 4800 rpm and then back -7° to 5000 rpm.

I strongly suggest you start with a proper base map for this engine. This is crab. I hope this was a beginner DIY map and nothing done by a professional. If the latter, I strongly suggest to change shop.
 

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Discussion Starter · #11 ·
Update: so I finally got my car off of limp mode , I’ve been hella busy so I haven’t had time to check out the hatch n shit but today I discovered that the crank sensor connector was shit lol , (I bought a aftermarket one from a local shop so it’s not branded they made it ) the wires popped off the connector like nothing so no shit it wasn’t grabbing signal lol but yeah I replaced it with another connector and boom no more limp , I still haven’t driven the car yet but I’ll send another data log to mr.lotus to see if the car is running okay but i believe regardless I need a tune so yeah
 
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