TRM tune, rev limit went down to 6k

[sludge1300]

Pretty sure you're correct, I wired the sensor into the dash. It was however, disconnected before I bought the car. So, no road speed signal, i believe has ever run to this DME.

In other words, i don't know if it's ever had a rs signal, and yet the rev limiter worked fine last week.

I think i might need to pull out some wiring diagrams and stuff though, kinda forgetting how all that stuff is set up

[FredK]

Do you still have your stock instrument cluster installed, behind your Race Tech Dash 2?

I am 99% certain that your DME is no longer receiving a vehicle speed signal since you have an aftermarket dash. Ordinarily, the sensor in your diff would pass on rotational speed information to the E30 instrument cluster. From there, a signal would be passed to the DME from the instrument cluster, called the vehicle speed signal. The signal is absent, either because you don't have the stock instrument cluster, or even though it's installed behind your Race Tech Dash2, it has become corrupted, or something flaky is happening with your wiring.

[sludge1300]

I have an M52 in my e30. I finally installed my TRM tune a couple weeks ago, replacing the m50 chip/19 lb injectors with my TRM chip/21lb injectors.

I tested it on the road, and the rev limit was up to 7000, like it was supposed to be.

Once I started driving on track last weekend, the rev limit started kicking in at 6k. occasionally it would shoot up to like 6300 and then go back down, but otherwise, it was always stopping at 6k.

Any ideas what could cause this? It seemed to be running well otherwise.

Guess it's worth noting that i have a Race Tech Dash2. I don't see how it's possible that it could recalibrate the tach on its own, but perhaps somehow the scale changed? Doubt it tho since it read idle at just under 1k, which sounds right.