She stumbles... [Archive] - SaabCentral Forums

: She stumbles...

20th May 2004, 03:56 AM
Not without a little help from folks on this site, only a few days back I replaced the headgasket on my old '86 8v Saab 900 and have now driven her about 350 miles. All's fine, back to if not better than what it was before the head gasket blew, except for one thing: now again, while cruising at 50+MPH, she stumbles (or hiccup might be another way to put it) a few times over a few seconds before settling down again.

This has happened about six times in all now, and seems to occur mostly when driving uphill. Yesterday morning I cleaned the carburretor and gave it a new distributor hoping it might make a difference, but it did it again (just once)after about 50 miles of driving. Don't have a clue what to do or look for now. Any tips would be really appreciated.

20th May 2004, 07:09 AM
:idea Carbon deposits breaking up,or water in the tank? Try some carb cleaner in the tank .Pat

20th May 2004, 04:30 PM
Er... Do you mean carbon deposits breaking up in the combustion chamber? Would that cause such "stumble"? When I had the head out I cleaned the chambers' pistons with brake/clutch cleaner. I hope this wasn't a bad idea. Could that be why the carbon on the pistons is now breaking up? And if so, would it cause damage? And will the problem clear by itself?

By the way, did about 30 miles today and she behaved perfectly. Just purred. So...

Many thanks.

20th May 2004, 05:49 PM
It should just clear up by itself if my theory is correct.I still would use a bottle of cleaner to soften things up.I personaly never clean the pistons ,if it's running right it will clean itself.As far as carbon damaging the valves or fouling a plug,I wouldn't worry about it . :roll: .Pat

20th May 2004, 07:07 PM
Sounds like something loose and electrical to me.

Try checking for loose connections on the coil, distributor and ignition amp.

21st May 2004, 04:03 PM
Many thanks for the suggestions. Will get that cleaning done and check all those connections as well...
Did another 50 or so miles today and, once again, no sign of stumbling from the old girl. Who knows? At least it's beginning to look like I did an alright job of the head gasket replacement. Phew.