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Discussion Starter #1
Some time ago i tried to fit an aluminum manifold to my modified 147 1.6TS along with a larger bore throttle body. The idea was that the intake pipe of the manifold matched in bore the larger throttle body, so i would have smooth airflow whereas if i kept the original plastic manifold there would be a significant difference in bores between TB and intake pipe (6mm) that caused turbulence and a distinct hissing/whistling sound when the TB opened up.

The conversion seemed to work for a while but after some days i got a "motor control system failure". When we linked the car's ECU to an examiner we found two error codes. P1176 and P1173 that suggested that there was an air leak after the MAF. We checked again and again the whole manifold/TB assembly for leaks and found none. We cleared the errors but they persisted so we decided to remove the aluminum manifold and larger TB and put back the old ones.

Some months ago a friend of mine with a similar car decided to fit the variable intake manifold of the 1.8/2.0 litre version to his 1.6TS. After some fiddling around with the wiring and rigging up a piggyback ECU to drive the manifold's actuator he made the thing work with a gain of about 5-7HP. However, some days after the installation he got the same error codes (P1176 and P1173) and was forced to revert back to the stock static manifold.

This strange coincidence has been bothering me, so i would like to ask anyone with knowledge to ECU programming, especially AlfaNige, if they know the reason of these errors and if they can be avoided somehow. My absolutely non-educated guess is that the MAP readings have changed due to the different shape of the intake manifold and they go off-scale compared to some internal map inside the ECU. Does this make any sense or is it rubbish? Any better explanations?
 

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You won't need to worry about the error code. This code comes up as a wrong interpretation of what is going on. All that is needed is a map adaptation. The reason for the codes coming on after a while is because the engine is not very often in the range where it detects the fault.

Pm me for more information.
 

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Discussion Starter #5
Is it OK if I post it here? If not may I email you directly?

Again thank you for your help.
 

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Discussion Starter #7
My friend told me that he got 5 more HP dynoed at the wheels at 500rpm higher than before (6000rpm before, 6500rpm after) while the curve was higher than the previous one throughout the rev range. That is until the checkengine appeared, the ECU went into "safe mode" and the engine lost power.
 
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