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Hello all, last night a couple of minutes after coming off the highway (constant 100-120kms for an hour), when i took off from a set of traffic lights the engine light came on and the car would not go over 2000rpm. All gauges are fine (temp and oil pressure) and there was no warning signs that i could tell of something was wrong. It felt like i was running out of fuel as i took off. I limped back home (12kms in 50kms streets) by manually shifting up the auto gearbox as they hit 2000rpm. The car was smooth and the gearbox normal. This morning i started the car and same thing with the car cold. I tried disconnecting the battery for a few minutes but no change. I have ordered an OBD2 dongle but my question is, do you think i can risk driving it to a workshop that is 20km away without knowing the error codes? The car seems to run ok in the low range so will have to avoid the highway. My suspicions lie with the fuel system but I am quite new to these cars. My last tank I had to fill up at a no-name petrol station on the highway that only had 95 RON and i was about 3/4 of the way through that tank. I usually run V-Power. Any thoughts?
 

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Sounds like a timing error and the cam phasers are out of sync. I Just hope you've not got an error code of P0016/17. You should be able to drive locally to your garage of choice. The car limps to hopefully stop the pistons smashing the exhaust values if the chain jumps a cog on the cam phasers


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Sounds like a timing error and the cam phasers are out of sync. I Just hope you've not got an error code of P0016/17. You should be able to drive locally to your garage of choice. The car limps to hopefully stop the pistons smashing the exhaust values if the chain jumps a cog on the cam phasers


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You don't get limp mode as such with stretched chains. The ecu just doesn't use the vvt system, it leaves it in the high rev setting which means loss of torque below 4000rpm.

Its a very noticeable loss too - hills normally climbed in top at 2000rpm, required 4000rpm in 3rd but on a level road the torque was adequate to maintain normal speeds but with very little throttle response - ie 90% of the gas pedal travel did nothing.

On my previous Brera, I had those fault codes numerous times + warning light and torque loss and whether reset or not, the performance was the same - no limp mode and when you hit 4000rpm the performance is back to normal. A

It also states in elearn that in the event the vvt system isn't working, the engine will still develop the quoted torque and bhp figures. This is understandable, since vvt systems are intended to boost low down torque on relatively highly tuned engines (so below 4000rpm on the V6)
 

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You don't get limp mode as such with stretched chains. The ecu just doesn't use the vvt system, it leaves it in the high rev setting which means loss of torque below 4000rpm.



Its a very noticeable loss too - hills normally climbed in top at 2000rpm, required 4000rpm in 3rd but on a level road the torque was adequate to maintain normal speeds but with very little throttle response - ie 90% of the gas pedal travel did nothing.



On my previous Brera, I had those fault codes numerous times + warning light and torque loss and whether reset or not, the performance was the same - no limp mode and when you hit 4000rpm the performance is back to normal. A



It also states in elearn that in the event the vvt system isn't working, the engine will still develop the quoted torque and bhp figures. This is understandable, since vvt systems are intended to boost low down torque on relatively highly tuned engines (so below 4000rpm on the V6)


It could well be a multitude of things that causes limp mode, your right the ECU is shutting the cars power down, but why? Likelihood is to stop catastrophic damage to what ever the fault is, engine, automatic transmission, who knows until he's had his fault codes read. If his primary chain is slack or the cam phasers jumped a tooth and damage something it'll defiantly go into limp mode then. As an educated guess it's more-than-likely the chains


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It could well be a multitude of things that causes limp mode, your right the ECU is shutting the cars power down, but why? Likelihood is to stop catastrophic damage to what ever the fault is, engine, automatic transmission, who knows until he's had his fault codes read. If his primary chain is slack or the cam phasers jumped a tooth and damage something it'll defiantly go into limp mode then. As an educated guess it's more-than-likely the chains


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The ecu compares the desired cam positions with the actual position and within the window of acceptability. It will do this by looking at the duty cycle needed to achieve the desired position and if this cannot be attained without an excessive duty cycle it will log the fault codes and cease to alter the variator position.

It's quite possible that if the cam positions are way out such as by a chain jumping a tooth, that it will invoke true limp mode. In which case the performance even at 4000+rpm would also be poor but I would expect rough running, possible pinking and misfiring. However I think the ecu would just shutdown the engine to prevent damage rather than going into limp mode.

But you're right, it could well be other issues so reading the fault codes will help
 

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Hello all,

Thanks for the replies and information. I'll be sure to post what error codes come up. It gets worse i'm afraid. I went back to the car this afternoon to take it to my mechanic but now there were twice as many issues! I made a little video and sent it to him as i think the car is un-drivable now. Now when i turn on the ignition i get no VDC and Hill Holder available as well as Check Gearbox. The fuel gauge works but as soon as i push to start it drops to zero with the light flashing. The most worrying thing is the almighty thump when i put it in D. Doesn't happen every time but it's not nice when it does. I can drive in D (also flashing) but the paddle shifts are gone.


The mechanic seems to think (without having seen the car) that it might be electrical like the engine earth or something. Does that seem plausible? I have to travel for work so probably won't get it to him until Monday next week. By then i should have my OBD2 reader as well.

Thanks again.
 

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Hello all,

Thanks for the replies and information. I'll be sure to post what error codes come up. It gets worse i'm afraid. I went back to the car this afternoon to take it to my mechanic but now there were twice as many issues! I made a little video and sent it to him as i think the car is un-drivable now. Now when i turn on the ignition i get no VDC and Hill Holder available as well as Check Gearbox. The fuel gauge works but as soon as i push to start it drops to zero with the light flashing. The most worrying thing is the almighty thump when i put it in D. Doesn't happen every time but it's not nice when it does. I can drive in D (also flashing) but the paddle shifts are gone.

https://www.youtube.com/watch?v=-As5LZjVdZ8&feature=youtu.be

The mechanic seems to think (without having seen the car) that it might be electrical like the engine earth or something. Does that seem plausible? I have to travel for work so probably won't get it to him until Monday next week. By then i should have my OBD2 reader as well.

Thanks again.
Good news in a way as its probably not the timing chains and it may be as simple as a bad earth or simply a worn out battery (how old is it?)

If you can borrow a good battery try this and also check the battery lead connections are clean and not loose.
 

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Good news in a way as its probably not the timing chains and it may be as simple as a bad earth or simply a worn out battery (how old is it?)

If you can borrow a good battery try this and also check the battery lead connections are clean and not loose.
The battery was put in new 6 months ago when i bought the car and it all looks clean with no corrosion whatsoever. If there was a gearbox fault, would the car go into limp mode? The only other thing i have noticed lately (the last week or so) is a sound in the dashboard that sounds like paper flapping around when the heater is on. Probably not related but it's the only fault i have noticed of late. I did also have the cruise control stop working intermittently twice soon after i got the car but hasn't happened for a long time. Other than that, the car has been faultless.

Cheers
 
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I had a similar problem as a result of a bad battery, threw up all sorts of error codes. ECU went into limp mode and continued there even after replacing the battery. It took the clearing of All error codes before the kitten would purr again.

Check you battery connections-tightness on positive terminal, earths, yellow reset button (could be playing up)etc

ahh already suggested by Oldie :)
 

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Hi guys, I thought i should report back and let you know what caused all the faults. Turns out a heat shield came loose and pressed the wires of the two rear lambda sensors onto the tail shaft which eventually wore through the cable exposing the wire and causing the problem. Kind of relieved as it's a mechanical mishap as opposed to a serious electrical fault! :thumbup: Thanks for all the replies.
 

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