BMW 740, engine failure, vibration and poor acceleration

[lollis]

Hey.
I have a BMW E38 740ia 1997 model that I have an engine failure. I have checked the spark plugs, coil and tested on the sucking false air.
The engine sucking false air and I will replace the seals so this problem goes away.
I've made ​​a diagnosis with Carsoft 6.5 and the error codes that have come up are:

75 Random/Multiple: Misfiring in several cylinders.
158 Activation. fuel injector. cylinder 9 ( wtf..? =s )
153 Activation. fuel injector. cylinder 4
138 Compressor intervention.

I erased the error codes, and while the engine was idling and got them up here right away:

10 Signal. oxygen sensor before cat. (Bank1 Sensor1)
211 Knock Sensor 2 (Bank 2)


I took a test ride to see if it came up a few more error codes and the codes that came up were these:


10 Signal. oxygen sensor before cat. (bank1 sensor1)
211 Knock Sensor 2 (Bank 2)
254
254

When I came home and cleared the error codes for the test ride I let the engine stand idle while I cleared the error codes, suddenly started the engine to stop and started to vibrate and go on all 8 cylinders when I delete the error codes.


I have filmed some videos to show how the car behaves ..
[ame]http://www.youtube.com/watch?v=3qARBBtH8O8[/ame] - This is full throttle from 0-130 km / h to show how bad the engine is running, note the end of the second gear.

[ame]http://www.youtube.com/watch?v=pqXc6p6HV9k[/ame] - How much the car shakes and the sound from the exhaust system by overspeed when the problem is "enabled", sounds like a lot of unburned fuel in the exhaust system ..?

[ame]http://www.youtube.com/watch?v=3WCU2ZeUhX8[/ame] - problem "enabled" to "disabled" after starting the engine again.

[ame]http://www.youtube.com/watch?v=jEd2xcNNVCk[/ame] - Same as the movie over here, just filmed from the rear exhaust, notice the vibration in the exhaust pipe when the problem is on and the start of larger vibration than when the engine is started.

[ame]http://www.youtube.com/watch?v=7dZKnv8bY9E[/ame] - Filmed engine at idle when the problem is "enabled", impossible to see the movement when the problem is not there.


My English is not the best so thank you, Google Translate :P

[Timm]

The error codes point towards a blocked catalytic converter on Bank 1. The restriction makes Bank 2 run much too lean and is the cause of the knocking and error code. It also causes the mixture to be incorrect on both banks and is the source of the O2 sensor error codes and the misfires.

To see if this is the problem, physically remove both pre-cat O2 sensors and go for a quick run. Alternatively, have the pressure tested at the pre-cat sensor fittings.

P.S. The code-reader you are using is using the wrong error table, that is the reason for the cylinder 9 error.

[Mayorchuck]

Welcome to the forum.

[bmwbob89]

I agree with Timm. That's the first thing I do when they won't go. Plugged cat will stop the car in its tracks. Pull the O2's and see if accelerates.

[andsteve]

I feel like i've heard of this before, but I can't recall; pretty much everything was the cause of one thing going wrong. Has the engine compartment been exposed to significant amounts of water lately? ie. very heavy rain, washing the engine, ect.

Things that I would test:
1) Voltage (with engine running)- Do this using the OBC in the cluster
2) The MAF- this can cause rough idle and other issues
3) Fuel pressure (if you can)- obvious reasons
4) Intake leaks- Use carb cleaner and follow the intake while spraying the intake connections to see if the idle increases.

Things that I would have an Indy check (or if you have the knowledge and tools):
1)Timing- I couldn't tell from the video, but these engines are known for their crappy timing chain guides. While not destructive, slightly incorrect timing can hinder performance and cause all sorts of issues.
2) Compression- Possibly bad compression. Would also cause engine issues.

Hopefully some other people can add to this list, Good luck, and welcome to the forum!

The error codes point towards a blocked catalytic converter on Bank 1. The restriction makes Bank 2 run much too lean and is the cause of the knocking and error code. It also causes the mixture to be incorrect on both banks and is the source of the O2 sensor error codes and the misfires.

To see if this is the problem, physically remove both pre-cat O2 sensors and go for a quick run. Alternatively, have the pressure tested at the pre-cat sensor fittings.

P.S. The code-reader you are using is using the wrong error table, that is the reason for the cylinder 9 error.

This is what I was thinking of...

[lollis]

Hello again. Thanks for any response so far!
I plugged away 2 of the cables to the sensors behind the cat, but is the 2 before the cat too? That case should I disconnect the last 2 out tomorrow and take a test ride.

Thx guys! :-D

[Timm]

The two O2 sensors BEFORE the catalytic converters need to be physically removed, not just the connectors. The two behind the cats stay in place.

[lollis]

The two O2 sensors BEFORE the catalytic converters need to be physically removed, not just the connectors. The two behind the cats stay in place.

Okay, but if I take out the O2 sensors, it will not be a hole in the exhaust then?
Will get this done tomorrow!

[Mayorchuck]

That's the whole point lollis. If the cats are plugged, removing the sensors allows the pressure an avenue to release. If this improves your condition, you know the cats need to be replaced.

[lollis]

That's the whole point lollis. If the cats are plugged, removing the sensors allows the pressure an avenue to release. If this improves your condition, you know the cats need to be replaced.

Hehe, okay but then I'm in! Updating tomorrow when I have tested it! :-D Thx!

[andsteve]

Hehe, okay but then I'm in! Updating tomorrow when I have tested it! :-D Thx!

You sound way too excited for bad cats..

[lollis]

You sound way too excited for bad cats..

Hehe, I'm not thrilled that the cat might be broken, but am glad that this might be the problem so the engine can be healthy! :-D

[Chief Jimbo]

How long has your traction control light been on? Did this problem show up when this light came on? What was done to the car before this problem showed up?

[lollis]

How long has your traction control light been on? Did this problem show up when this light came on? What was done to the car before this problem showed up?

Traction control lamp has not been on when the problem has been there. Traction control lamp lights up if I plug out the air flow meter.

Then I removed the O2 sensor before the cat and the car is like before again! :-D
But during the test ride when I was on my way home, then the problem started again. Is this because the cat is blocked and there is not enough flow for the exhaust?

Thank for all your help:-D

[Timm]

The hole that the O2 sensor is fitted too is not large enough to let all the gasses from the exhaust out - the test should be done at low power/idle, also be careful the gasses don't set fire to something on a long test (I should have mentioned this before really).

You also need to reset the adaptations which will be right at their limits.