Jazz motor light on and jerks !!!!

Hello all, I have a Jazz Bj 2006 1339cm3. Last week suddenly the engine light went on and he started to jerk. So I got to the right warning flasher and turned off the car. After I started the car again he drove again quite normal however the engine light remained on. The from the car workshop then have read out the error memory but also did not become really clever from it and told me to check this with a Honda dealer properly I’m sorry, but they just told me that it’s probably something to do with the throttle valve or rather with the sensor. So I went to my local Honda dealer and he also read out the fault memory. First they said that the throttle flaps are ONLY dirty and that needs to be cleaned (approx. 80€) afterwards the error should not occur any more. The next day my husband then called there to ask what is going on…. The car is back in order and can be removed. … so still paid there and gnashing of teeth…. The car drove as normal as always. As far as so good, we were still on the road at the same Aben and suddenly the himself again from the front, jerking, motor lamp on, turn off etc.. So my husband said again and then they said that the throttle flaps unit was defective and that the completely exchange t must be. Price approx. 600€ plus installation…. Now avoid question, is this error known in the Honda Jazz and isn’t that somehow cheaper to get there? I really don’t have a bit of trust to the Honda dealer anymore and feel like I’m getting off the hook…. Can’t you even give me a tip on how to proceed? MfG Angelika