Last week i tuned a 94 1.8 for a client with ms2.
the car has a broken afr gauge in the sence that it does work for monitoring bit doesnt give a voltage signal to the ms(wil be sent back for waranty).

so i decided while i stil have the gauge i would make a tune so my client can move the car.
i disabled al ego o2 correction settings and modified the map manually to get good afr's under most circumstances .hoping to finetune it when i get the gauge back or a new one.

my client picked up the car and it drove so good that he couldt restrain himself and went driving alot first 2 days until while driving his battery terminal got disconnected.

after he reconnected the battery the car was way way rich al around and was even idling at 9 afr.
ive tried to lower fuel and even at crazy low levels it now idles high 11's.
i have the car back now and can datalog but i dont think it wil be usefull because i cant see afr on the log.
im stuck, annyone ever had annything hapen like this or know where i need to start looking?

 

Sure its not a bad Vac leak?

 

Yes it was.the cause was a china bov. Coincidentally the battery happened that same day and thats when he noticed it.strangellybthe map signal was readding good so that threw me off but i blocked the bov and it was back to normal.relieved i didnt burn annything in the ecu

 

Glad you got it sorted.

 

Thanks.ive got thrown off track because my client only noticed it when his battery got disconnected but it was apparently earlyer that the problem started.so i tought i fried sommething from the overvoltage of the alternator.

what was it that caused your problem?

 

The wife accidentally kicked out the ecu vac line under the dash.

 

Yeah those are the things you least expect and go look and analize every other little thing and then in the end it comes down to something so simple