Author Topic: Rev limiter location and repair? (Read 10756 times)

a930rocket · « **on:** January 02, 2012, 03:37:06 PM »

I took the car for a good drive yesterday (first time) and when I revved to about 4300-4500 RPM, the engine started cutting out like a rev limiter was kicking in. The engine/car runs great up until that point. With the red line at 6k +, what is going on? Where is the rev liniter and what can I do to check it?

The other thought is the tach is off and I really am hitting the rev limiter?

DesktopDave · « **Reply #1 on:** January 02, 2012, 04:36:21 PM »

Rev limiter is integrated with the computer, it can only be changed with a little chip tuning.

You haven't swapped the cluster by any chance, have you?

carlos318is · « **Reply #2 on:** January 02, 2012, 04:37:34 PM »

You will tell from the engine screaming if you hit the limit

It could be a fuel problem

bmwconnect · « **Reply #3 on:** January 02, 2012, 05:41:55 PM »

DME#175 E30 318is

4500rpm limiter is speed threshold for tacho signal fault detection.

a930rocket · « **Reply #4 on:** January 03, 2012, 11:51:28 AM »

I've had the car since April, but this was the first time I drove the car hard. I was in a pack of two Porsche 911 Turbos trying to keep up through the back roads.

Dave - The cluster has not been swapped out to my knowledge.

Carlos - It did not appear that the engine was screaming (the car is quiet as a mouse with the stock exhaust), but then I'm used to a 911 Turbo with a open exhaust and a 7500 RPM limit.

bmwconnect - What does that mean? Can you expand on it some more?

Thanks guys!

Jim

doitover · « **Reply #5 on:** January 03, 2012, 12:43:25 PM »

Do you get any codes from a stomp test?

There are a lot of things that could cause this, AFM, coils, sparkplug wires, and fuel pump/filter among them.

bmwconnect · « **Reply #6 on:** January 03, 2012, 01:44:47 PM »

Quote from: a930rocket;109343

bmwconnect - What does that mean? Can you expand on it some more?

Thanks guys!

Jim

If the car is indeed limiting at 4500 then there is indeed a signal problem at the instrument cluster. I believe that's why desktop dave asked you if you have swapped it out lately

cheers

a930rocket · « **Reply #7 on:** January 03, 2012, 07:19:11 PM »

The cluster may well have been swapped out over the years. What do I need to check for and what's rhe right cluster?

atdm3 · « **Reply #8 on:** January 05, 2012, 01:21:04 PM »

You might also check your throttle cable. It could be binding ..

a930rocket · « **Reply #9 on:** January 07, 2012, 11:51:33 PM »

Cable seems good.

It's just a cut out at ~4300 RPMS.

Quote from: atdm3;109412

You might also check your throttle cable. It could be binding ..

colin86325 · « **Reply #10 on:** January 08, 2012, 09:00:53 PM »

My M3 (4-banger) had a coding plug or a cluster from a 6-cylinder installed, so I was only reading 2/3 the rpms that I should have.
I had another M3 owner drive next me at a given speed and yell his rpms out to me as I compared mine. This is how I confirmed my suspicions.

gearheadE30 · « **Reply #11 on:** February 08, 2012, 07:26:32 PM »

Crank and cam sensors should be on the list of things to check. If either has noise issues or is at the end of its life, it won't work well at higher revs when there is more noise and the pulses are more rapid.

bmwman91 · « **Reply #12 on:** April 24, 2012, 02:25:24 AM »

Get a multimeter out & check the resistance between pins 1 & 2 on the cam & crank sensor plugs. Report the findings here.

If those check out, then you should check the part number on the little blue coding plug that resides in the front of the instrument cluster. To get at it, you need to remove the pedal cover & knee bolster, and then a couple of black thumbscrews up inside the dash that hold the black plastic trim piece that sits over the steering column. It is a pain to get out, and I usually end up yanking it out. The plug can then be seen in the bottom-right corner of the cluster. Report the PN stamped into it, if the cam & crank sensors check out.

doitover · « **Reply #13 on:** April 24, 2012, 12:55:41 PM »

If the trim around the cluster is really difficult to remove, try loosening the bolt on the driver's side that holds the dash and pushing the whole dash up. I assume they drop over time.

Quote from: bmwman91;112093

Get a multimeter out & check the resistance between pins 1 & 2 on the cam & crank sensor plugs. Report the findings here.

If those check out, then you should check the part number on the little blue coding plug that resides in the front of the instrument cluster. To get at it, you need to remove the pedal cover & knee bolster, and then a couple of black thumbscrews up inside the dash that hold the black plastic trim piece that sits over the steering column. It is a pain to get out, and I usually end up yanking it out. The plug can then be seen in the bottom-right corner of the cluster. Report the PN stamped into it, if the cam & crank sensors check out.

bmwman91 · « **Reply #14 on:** April 24, 2012, 01:32:14 PM »

Quote from: doitover;112102

If the trim around the cluster is really difficult to remove, try loosening the bolt on the driver's side that holds the dash and pushing the whole dash up. I assume they drop over time.

Hmm...never thought of that! Where is it, exactly?