[jordanlloyd]

My relatively new-to-me '96 Eurovan (manual, 2.5L) is experiencing a weird surge/shudder/hiccup when reaching a certain speed. It'll happen pretty much everytime you hover around 95-100km/hr (~60mph?) and again at around 115km/hr, but nowhere else. It you just avoid cruising at these speeds you almost wouldn't know this problem exists. The van will hiccup and chug for a second or two when it happens, until you get out of these pockets.

There's a bit of a patch job on one of the hoses that I think is leading from the secondary air pump up to the air intake/cleaner housing (?). It looks like it had split a bit and was potentially letting some air in.

There's a picture here, I've attempted to reseal it in the meantime just in case this was the cause, but the problem still persists, so this could be related or not to the problem. What's the best way to fix this connection? I can't seem to track down if I can just replace the part it's connecting to, or if the whole air cleaner housing is one big piece (which it appears to be), which doesn't seem to be too readily available to replace.

Any tips on what to look into would be appreciated, obviously a bit of a newbie with this stuff!

[albertr]

If it's speed-related, then it might be related to certain RPMS. I would check motor/transmission mounts to make sure they are not bad.

-albertr

[M.steward77]

And normally vacuum leak problems tend to not be noticeable the faster you are driving because more and more air is being sucked in, where at idle you would be more likely to notice the problem

[jordanlloyd]

So turns out it looks like my problem was a failing ignition coil. Mechanic had a bit of a time trying to figure out just what was going on, but once they identified and swapped it out it's back to normal, no more pockets of hesitation/shuttering which is great.