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Discussion Starter · #1 ·
Since I have my car it never behaved right.

Facts:
- new Marelli AFM since yesterday - car became even worse ( I am not sure if it was necessary - the new unit reads very different values than MES gives as target, just like the original BOSCH unit did, it reads ca. the double amount of air . In case of the BOSCH unit at idle the delivered qty of air was identical with the MES target value but as soon revolution raised values became the double of the MES values. The Marelli unit reads already at idle the double value of the MES target value and keeps that in higher rpm levels too - is the MES value good? )

- tehoretically good TPS / idle valve ( I have alredy 4, all used ) - ( small motor tested, it works fine, TPS curve is without drops - tested using MES, so I assume the TPS unit is fine too )

- slight problem is, that none of the TPS passed the MES test ( is there any unit which passes it, or do I do something not right ) - however I never tested them so that previously I resetted them as I coudnt do that without the registered version ( now I can ), maybe that was the reason not passing the MES test.

- today resetted the ECU using MES ( today got registered )

- at first test car is MUCH much better, especially idle rpm level ( stable and perfect level ) and fine throttle response ( closing the throttle does not cause inmediate engine brake, ) I was really delighted.

- later today after starting the engine on the first 200 meters the same out of breath feeling, car does not accelerate, then suddenly that disappears, but car has the same little jerky behavour, it does not like low rpm driving ( which is a problem in the city ), then on the highway accelerating until 5.500 in 3rd, 4th and 5th arriving to the village and car behaves fine.

So what the hell is going here, I could use little help really.

The flow meter causes the problem? Its new.

The TPS is worn and contact isn't perfect? Then why I can't see any drop on the graphic test?

Your help is appreciated.

Best regards

Gergő
 

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I had a problem with mine, idle was fine when cold, then when driving no pull at low rpm (below 2k) but fine when cruising. I went through many checks, maf, throttle, ecu reset, coil packs only to find it was actually a cracked spark plug. Replaced all 8 in the end.
May not be same issue for you but perhaps worth a check.
 
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