Car is in limp mode

Tiny
CHRIS098
  • MEMBER
  • 2007 BMW 320I
  • 2.0L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 7,234 MILES
Car has a misfire. Checked coils and plugs and fuel pump. Code reader said injection changed that problem still there. Been told my chain maybe have slipped. Have not done a compression test yet. Car still starts and drives but no power in limp mode. I am not still driving car atm. But if the chain had slipped would it not damage other stuff? And would car still start etc?

And would a slipped chain cause low compression? In one chamber?
Saturday, September 8th, 2018 AT 11:15 AM

28 Replies

Tiny
KEN L
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The car goes into limp mode when the computer has detected a problem. Can I get the codes numbers that would really help? Here is a guide:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Also, if the throttle bore is dirty it will go into limp mode as well this is a common problem with all non throttle cable cars.

https://www.2carpros.com/articles/throttle-actuator-service

If the chain was off you would have low compression in all cylinders. Please run down these guides and report back.

Cheers, Ken
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Sunday, September 9th, 2018 AT 1:36 PM
Tiny
CHRIS098
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Hi Ken, yeah I did code reader came back as the injection. So I changed that and engine light still on.

I am getting a compression test on the weekend.

If my chain slipped would the crank sensor not throw a code? I am starting to think my chain maybe stretched and it is not closing either intake value or exhaust value which would cause low compression? As it seems the only be on chamber four changed coil and plugs.

Maybe guard rail has broken?

When cars not in gear it revs up fine and seems to have full power just when I drive it it struggle to get up speed.

I am no expert just what I am thinking.

Would a throttle body throw a code?

Thank you for your input Ken.
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Monday, September 10th, 2018 AT 6:45 AM
Tiny
KEN L
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The throttle body service may not throw a code. Here is a guide to help you do the compression test:

https://www.2carpros.com/articles/how-to-test-engine-compression

If the chain slipped it would produce a code. Does the engine make change noises? Can you please shoot a quick video with your phone so we can hear the noise? That would be great. You can upload it here with your response.

The misfire can be causing the issue.

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Monday, September 10th, 2018 AT 11:01 AM
Tiny
CHRIS098
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Thanks for reply so soon Ken.

The engine noise sounds like a chat chatting like a lose chain and sometimes when I start it up can hear chain hitting guard rail but not all the time I am not with the car at the moment it is back home.

Yeah, if it had slipped crank sensor would throw a code?

If my chain was loose and cars in limp would would it have damaged anything in my engine is my main concern.

Car still drives and when not in gear revs fine.

The engine noise is not loud at all, but can here a little noise and engine shakes as it is misfiring.

When I go home Friday I will get a video of the engine noise.

Saturday it is going in the garage I do not want to get ripped off so I want to know if a loose chain would damage my engine?
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Tuesday, September 11th, 2018 AT 8:59 AM
Tiny
KEN L
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It is possible the engine is hurt if the timing chain is worn/guides broken. The only way to know for sure is to do a compression test or shoot a video of it running and I can tell from that. Please let me know.
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Tuesday, September 11th, 2018 AT 12:27 PM
Tiny
CHRIS098
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Would a worn chain cause low compression?

Yeah, I will send video Friday and keep you up dated. Thanks for your input.
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Tuesday, September 11th, 2018 AT 12:32 PM
Tiny
KEN L
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Yes, if it has jumped time the compression will be low. Looking forward to the video.
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Wednesday, September 12th, 2018 AT 10:05 AM
Tiny
CHRIS098
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Thanks.

Would it be same if the tensioner as no good?

As I think it maybe just loose?

Or snapped rail would that cause low compression on one cylinder?
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Wednesday, September 12th, 2018 AT 9:21 PM
Tiny
CHRIS098
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I have taken a video ken but not sure how to send it?
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Saturday, September 15th, 2018 AT 4:05 AM
Tiny
CHRIS098
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Think I have sent it?
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Saturday, September 15th, 2018 AT 4:57 AM
Tiny
CHRIS098
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Smoking is a leaking rocker cover gasket. I think was like that before the noise was there.
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Saturday, September 15th, 2018 AT 4:58 AM
Tiny
KEN L
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Thanks for the video. It sounds like the timing chain guide is broken or you have a vanos that is out either way the front of the engine needs to come apart to see what is going on. Here here the diagrams to help us do the job. I will walk you through the repair. You can get the parts and tools from Ebay. This will not cause low compression on one cylinder though so that is a concern. How low is it? Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.
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Sunday, September 16th, 2018 AT 1:50 PM
Tiny
CHRIS098
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Hi Ken, thanks for reply. I am not doing work myself as it is a bit too much for me. So it is in garage ATM. I will ask him about the compression tomorrow when he checks the car over.
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Sunday, September 16th, 2018 AT 2:16 PM
Tiny
CHRIS098
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If a piston was worn or damaged etc, would I hear that?
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Sunday, September 16th, 2018 AT 2:20 PM
Tiny
KEN L
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Only sometimes. Can you tell if the noise is coming from the front of the engine or the middle?
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Sunday, September 16th, 2018 AT 3:14 PM
Tiny
CHRIS098
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Front I would say but not 100% sure and that noise just sounds like the chain? The car still drives just in limp mode would it drive if piston was damaged?

I am thinking worst now not good car only has 65,000 on clock as well. :(
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Sunday, September 16th, 2018 AT 3:21 PM
Tiny
KEN L
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Yep, that is the timing chain. With that many miles it is worth fixing if you can try to get pictures of the broken parts once you get it apart so people can see what goes wrong with them.
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Monday, September 17th, 2018 AT 11:21 AM
Tiny
CHRIS098
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But if it is low on compression in one chamber it is another problem not just the chain is it not?
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Monday, September 17th, 2018 AT 11:27 AM
Tiny
KEN L
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Correct, how low is it?
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Tuesday, September 18th, 2018 AT 9:21 AM
Tiny
CHRIS098
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Will find out tomorrow Ken and let you know.
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Tuesday, September 18th, 2018 AT 5:48 PM

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