jerking at high speeds
Seems this is more common than you think but with no immedite solution. I have (2) 2003 Bonneville SLE'* and they both do this. right around 4200 rpm. Both have had full recent tune ups (plugs,wires, filters, intake gaskets, FPR etc). They run great except for this condition. The two possible answers I have got is fuel pressure related like the pump is weak and the catalytic convertor is clogged. Have not had a chance to check the fuel prssure yet. Not really an issue, Maybe slows the kids down a little. Really would like to find out though. I am thinking that the one with 180,000 probaly needs a converter but lot of money to spend and find out that is not it.