Did Jesus uphold the inerrancy of the Old Testament?

Jesus knew the Old Testament was True; He also knew we didn't understand it well enough to know how to receive all that God wanted us to receive.  Mankind needed Jesus Christ to come > to free us from all that holds us in spiritual bondage, to open both our hearts, and minds towards God; as our Way-shower. To receive the Holy Spirit who will guide us into All Truth.  The trouble is that we see in part still, as Paul stated.   

 Had Jesus thought the Word of God was wrong, he would of told us! 

It is so important we see this significance of all that he was undoing. So we could enter into the Holy of Holies after Him.  He is the Fulfilment of the prophecies.  

I don't know if I am saying this correctly but personally I believe the jots and the tittles need to be fulfilled in us through His Love and all the admonitions of the Holy Spirit; so we can enter the Holy of Holies with His Love and Spirit by adorning ourselves in Christ.  Until we come unto Jesus Christ we are under The Law.  To be reconciled we must come and abide in and with Christ.  ( in order that the righteous requirement of the law might be fully met in us, who do not live according to the flesh but according to the Spirit.)

The Old Testament isn't inerrant, it is us who are in error, more often than not!  

Of course he did, but the passage you cite speaks of the old law passing away, once all is fulfilled. Jesus later told his Apostles: Luke 24:44  And he said to them: These are the words which I spoke to you while I was yet with you, **** that all things must needs be fulfilled which are written in the law of Moses and in the prophets and in the psalms, concerning me.*****Luke 24:45  Then he opened their understanding, that they might understand the scriptures. (Jesus fulfilled all things. No more old law. No more Old Covenant. Only the new and better Covenant in his blood.) 

No.  Fullfil means to complete, correct, adjust, or whatever necessary to make perfectly right.

God's WORD never changes: The same Gospel was taught by ADAM, MELCHIZEDEK, JESUS, and SIMON PETER BARJONA. During an independent Nation/Church as Israel once was, CHURCH and Government were combined; so GOSPEL and LAW was combined. Christ fulfilled the Law by placing God's Law (GOSPEL) under the Apostles and Moses law (government) under the Pharisees. Moses had combined Kingdom Law with government: Today, government is under the control of government officials where the Health Dept. regulates food laws.

Christ fixed Moses' mess, then Paul comes along and messes it up again.

He put it in its proper place.  He DID fulfill the Law and the Prophets.  He said "I give you a NEW covenant....".  There were a number of things regarded as "rules" of the OT that He dismissed.  "You have heard it say 'An eye for an eye, a tooth for a tooth." but I say to you do not resist the evil person."  In the dream to Peter He dismissed the OT dietary restrictions.  Unlike Jewish teaching that something which enters a person can make them unclean Christ said that it was what comes out of a man, not into him that can make him unclean. 

Not the inerrancy of the bible, but the underlying law.

His death on the cross fulfilled the law, and we came into grace

The people the OT is most important to seem to think he didn't meet its qualifications for the Messiah. So there are probably a few details he'd rather you gloss over.

Jesus fulfilled the law, so it has passed away.

Matthew 19:8

He *said to them, “Because of your hardness of heart Moses permitted you to divorce your wives; but from the beginning it has not been this way.

The above clearly points out that one has to have a very broad definition of inerrant. 

So does that mean Jesus believed the ridiculous Noah's Ark myth? What an idiot!

Jesus interpolated right out of the old myth . It's his daddy . grandaddy and Skydaddy .