Engine Cuts OFF / TPS

[kod81]

Hi,

I just posted a new topic, but it never appeared on the forum so apologize if this is double posting.

My car is E30 318i M40B18.

The car has recently developed a fault where it cuts off at a higher RPM. When accelerating it get to about 5200RPM then cuts off. When accelerating slowly it will get to around 5700-5900RPM then cuts off. First time it's done it, the engine didn't stall but every time I pressed on gas pedal it just just sort of "spiked". Second time, the engine didn't stall but when I pressed on gas pedal nothing was happening. Like a dead pedal. Each time switching engine off and back on resovled the acceleration issue, but not the reving one.

My first suspects were air, fuel and ignition
- I have a nearly new rotor arm (replaced nearly 10 months ago but done maybe 3000miles max)
- I have a nearly new spark plugs - replaced as above. I removed two for inspection and they seem normal.
- I checked resistance on the coil and it reads as expected
- no visible damage or wear to the distributor
- HT leads not changed
- new fuel filter
- second hand AFM
- new rubber hose
- resistance on cranshaft position sensor is as expected

-I checked the TPS and there's no continuity at all. Neither with close throttle nor with wide open. I no the access is fiddly but have been messuring like a million times and no luck. I guess that suggest the sensor is faulty? If so, would it cause my symptoms and would it now be the main suspect?

Thanks,

[kod81]

I haven't checked the pump nor the relay, as the TPS test threw me off....
Before I start spending money on new items, I wanted to see the community's thoughts and opinions on the TPS. Thanks

[jmc330i]

When you say it "cuts off", does the engine cut out or keep running but feel like it's hitting a rev limiter?

The revs limiting at around the 5k rpm mark on an M40 is usually a sign of a worn cam.

[kod81]

It feels like hitting a rev limiter.
The engine keeps running, it does not stall.
When I drive and it cuts out, I can't accelerate anymore until I switched the engine off and back on. I can press the pedal but nothing happens.
When I idle, I can still rev but not over 6k.

It feels fine in regards to power, but only revs to that 5200rpm mark.

I inspected the cam while replacing the seal last year (again, 3000miles ago) and it looked OK. I am aware of the M40 cam problems.
Also, it started doing it all of a sudden and not progressively.

Why my TPS shows no continuity? Does it mean is 100% dead?