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DISCUSSION => Engine + Driveline => Topic started by: sbarton on April 24, 2013, 02:56:26 PM

Title: M42 feels like it hits 4k rev limiter when it gets hot
Post by: sbarton on April 24, 2013, 02:56:26 PM

I've got an M42 swapped into a 1874 2002tii.  It runs fine when cold, but when it gets hot after running hard for 30-60 minutes it feels like it hits a rev limiter at 4000-5000rpm and get worse if I continue to drive it,  If I let the car rest for a bit and cool off, it is fine again. 

I've swapped the ECU, Coil Packs, AFM/MAF, and even the entire motor with engine wiring harness. 

I'm pretty sure it is electrical since it only happens when it is hot.  Any ideas/suggestions?

Thanks! 

-Scott

Title: Re: M42 feels like it hits 4k rev limiter when it gets hot
Post by: wazzu70 on April 24, 2013, 04:13:05 PM

I agree it sounds electrical. I would check all your sensors to verify they are working properly. The testing procedure for most of the sensors is in the bentley.

I would check crank and cam sensors, coolant temp, throttle position and AFM/MAF to start.

Title: Re: M42 feels like it hits 4k rev limiter when it gets hot
Post by: sbarton on April 26, 2013, 10:18:21 AM

Problem is that the all sensors are on the motor and I swapped motors.  So essentially different sensors, same issue. 

-Scott

Title: Re: M42 feels like it hits 4k rev limiter when it gets hot
Post by: wazzu70 on April 26, 2013, 11:40:07 AM

That does not mean all the sensors are goving the correct signal though. Did you change wiring harnesses as well?