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Discussion Starter #1
Quick q for those in the know. Is the rev limiter supposed to work in all gears? My injector light is on all the time now, which seemed roughly to coincide with me bouncing off the limiter in 2nd gear the other day, but is probably unrelated...maybe.

Today I was trying to get rid of the injector light by driving at high revs (erm, yes that does usually make it go away for a few weeks ;) ) in 3rd gear, but the rev limiter didn't do anything, it let me sail straight past 7k rpm :confused: :eek:

Any ideas???
 
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Discussion Starter #2
The rev limiter should work in any gear. Not sure what's going on there...
 

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Sounds like you have a dirty/faulty sensor! Try reseating all visable connections under the bonet as a matter of course.
 

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A faulty/disconnected knock sensor... should be in the bottom of the block
 

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Yes, that one... :p

knock- knock...
 
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Discussion Starter #6
I'm sure the 16v rev limiter is at 7200rpm. Did you go that high ????
 
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Discussion Starter #8
Ah, I always thought it was 7000. I may not have quite got to 7200 then. I'll give it another try on the way home from work tonight.

The injector light has gone off again anyway :confused:
 
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Discussion Starter #9
I'm not too sure what kind of limiter you have on your model however there are two types that I know of for 155s:

1. Soft (electronic - transient set at 7200min-1 and steady state at 7000min-1)
2. Hard (fuel cut-off)


I can assure you that the rev limiter has nothing to do with the fuel injection system malfunction. This may probably be related to the EGR valve as it usually comes on at part throttle and between 2000 and 5000min-1 when the valve is supposed to be doing its thing. By driving at high revs and full throttle you do not allow the EGR system to work and thus the engine is working fine. The minute you drive with those conditions where EGR comes in, there must be something going on that is upsetting the ECU and thus the light comes on. The car is still drivable as the ECU will revert to standard safe settings for operation however these are obviously not as desirable as when it is functioning in "closed-loop" mode where it tailors fuel supply, spark advance etc by monitoring and processing the signals from the Lambda oxygen sensor.

Taz.
 
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Discussion Starter #10
My mistake. I just always thought the limiter was at 7k. But I've tested it and it's definitely 7200 or thereabouts. So, just a pretend problem there.

Re: injector light I'm not sure what's going on. It's gone off again now. When I said I get rid of it by driving hard I mean for a few miles, nto that it goes off at higher revs straight away :confused:
 

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The rev limiter on these engines has been know to fail- saw a 145QV go bang at Knockhill- allegedly it reached about 8K! Don't know how that happened but perhaps you've got an intermittent fault developing. A workshop can only trace it when the fault actually occurs though! It will likely just become more frequent until the light is on all the time- wouldn't like to guess what though! :)
 
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Discussion Starter #12
ally said:
saw a 145QV go bang at Knockhill
Think me and Jase saw that one too. It came up the straight knocking like hell a couple of Alfa meets ago.
 

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marlon said:
Think me and Jase saw that one too. It came up the straight knocking like hell a couple of Alfa meets ago.
Can't understand how his wife doesn't want him to go back to Knockhill this month! :cheese:
 
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