hi experts
2004 max doesnt go above 20MPH and its makes bang when the grear shifts. i notices that it shows on 2 & 3 gear when i go in manual shifter.
it doesnt show 1, 4, and 5. there is service light on keep coming in for P1800. i recently replaced the VIAS part from autozone and the service light keep coming back on after erasing from memory. pls advice whats possible problem i am facing. is the valve body gone bad or entire tranny needs to be rebuilt ?
can P1800 cause these shift problems ?
thanks

 

It might. I'd suggest oem VIAS.

 

Thanks a lot for the advice sir you seem to know a lot about these maximal in particular? Tonight before all this happened I heard a slight knock in the motor but it soon shut up and my number 3 ark plug is not hurting like it dispose too. Has a slight miss to it?

 

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