Misfire? M40b16 engine loss of power, 5000rpm

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blood69
E30 Zone Newbie
E30 Zone Newbie
Posts: 13
Joined: Sun Feb 18, 2018 11:00 pm
Location: Funchal, Madeira Island

Wed Jun 05, 2019 2:00 pm

Hi everyone,

I'm having little problem with my 1990 E30 316i Euro Spec that's starting to pissing me off.

2 year ago i change a head gasket from a M40B16 engine . Also changed the following parts:

- Thermostat (Gates -> 87ºC)
- HT Leads (Magneti Marelli) - Disconnected the Pulse Generator
- Distributor Cap and Rotor (Bosch)
- Spark Plugs (Bosch - FGR7DQP)
- Fuel and Oil Filter (Bosch)
- Timing Belt and Tensioner (Gates)

After 3 months the car stalled on the middle of Traffic. After 10 minutes i was able to start it again but just for 30 seconds and it stalled again.
On the Shop they said it was a bad Fuel Pump. So i purchase a Bosch unit (BMW OE-16 14 1 179 992).

After they install it they said the Crankshaft Pulse Generator was bad too. So i purchase one (STARK) and also a new Blue Temp Sensor (Bosch) and a Throttle Position Sensor (Bosch). They were all installed and they call it Fixed.

The car run fine but immediately run into an issue that never happen before. Sometimes pulling 1st or 2nd gear to the max RPM wide open Throttle, the car loses power at nearly 5000 rpm, dropping the RPM like engine don't have strength to pull the car.
If i immediately change to the next gear the problem stops.
Also when happens i don't ear any misfire, but the car shakes a little bit, like its working with less a cylinder but i'm not sure.

This is specialty dangerous when i'm overtaking, since i never know when the car is going to do this.

The Shop couldn't replicate the problem and said everything was fine. This happens sometimes, like 2 in 10 times.

Do anyone have a clue what can cause this?
Thanks in advance.
danllew
E30 Zone Newbie
E30 Zone Newbie
Posts: 2
Joined: Mon Jun 03, 2019 8:32 am

Thu Jun 13, 2019 7:45 am

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blood69
E30 Zone Newbie
E30 Zone Newbie
Posts: 13
Joined: Sun Feb 18, 2018 11:00 pm
Location: Funchal, Madeira Island

Thu Jun 13, 2019 9:11 am

danllew wrote:
Thu Jun 13, 2019 7:45 am
https://www.e30zone.net/e30wiki/index.p ... _Over_5000

Could be a worn cam.
Hi, thanks for your reply.
I discard that possibility, since this happens 2 out of 10 times. If it was the cam worn it should happen all the time.

Also i have now a good idea of what it is.

Read This.
https://www.bimmerforums.com/forum/show ... ter)/page2
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