3000 RPM stumble like hitting a rev limiter

[ian11gti]

Hey everyone, I just bought this 1995 neon that has been swapped. It has a 2005 SRT 4 engine and trans and MSII set up.

My problem is that the car has been hacked together for the most part but i got it really cheap.

Heres my issue right now. I was cleaning up the wiring in the engine bay because a lot was hangin out of the loom and looked nasty, also the battery was relocated to the trunk and the guy had a god awful amount of 2 ga wire running from the battery to starter with no fuse. So i taped up the harness and installed a 125 amo circuit breaker.

After doing this the car will not rev past 3000 RPM its like launch controll is stuck on or its hitting a rev limiter. I turned off both the rev limiter and launch control and still have the same problem Everything appears to be set up correctly.

Is there any sort of relearn procedure that needs to be done after a battery disconnect? If not do you guys have any ideas? Im failrly new to Megasquirt but i have been reading a lot of information.

When i have tuning studio open and i hit 3000 RPM AF bounces all over the place and the red SYNC tab on the bottom of the screen flashes. Is this a crank sensor issue?

[esteinmaier]

Sounds like it. I can log in and take a look if you like.

[ian11gti]

That would be awesome. Can you tell me where to find the procedure for creating a log? Is that in mega manual?

[joe_blow88]

Every time I see post like these, I think its the tps wires/sensor. And it always is.

DROIDX using

[ian11gti]

I did the TPS recal and its still doing the same thing. Should TPS wires be shielded?

[nsrt4]

Maybe the cam sensor?

[Tonysrt4]

I had the same problem I replace the cam sensor with the magnet but nothing do I decide to replace the crank sensor problem solved


Autoguide

[ian11gti]

The cam sensor is not hooked up and I don't see a connector or anywhere. Issue? Lol

[Tonysrt4]

Check the crank sensor


Autoguide

[ian11gti]

Replaced the crank sensor same issue. Cleaned the grounds and added a additional engine ground and same issue.

It really seems like its something within the software like a limp mode or something similar how consistant it is and how it feels. Also this all started after pretty much a battery disconnect.

I did notice that all the sensors go to an engine ground. Shouldnt the megasquirt have a sensor ground i know chassis grounds cause a lot of interference or noise.

Is there any sort of calibration that could have changed or any sort of failsafe or limp mode within MSII that will not allow you to rev past 3000RPM?

Thanks again for all your help im really stumped with this one.

[ian11gti]

Im looking at some wiring guides and i see that most of the megasquirt systems do not use a 5 volt vref. The have there iwn dedicated power circuit. The one on the car right now splits off the TPS 5 volt and has a chassis ground and for some reason two signal circuits...

[Overcome]

Quote: Originally Posted by ian11gti

The cam sensor is not hooked up and I don't see a connector or anywhere. Issue? Lol

Did you ever connect the cam sensor?

[ian11gti]

The cam sensor was never connected. I do not think the megasquirt utilizes it.

[theGrownsamonie]

Can you give more details on which Megasquirt you are working with?

[ian11gti]

Tuning studio identified it as version 2.0.1.