So i was driving my 90 K5 the other day and i noticed as i was on the freeway it was acting funny. I can only feel it when i'm coasting and it feels like i am slightly tapping the breaks in a pulsing pattern. I tried searching for similar problem with no luck and was hoping someone might be able to point me in a direction on where to look or what to search... Thanks
CK5
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Weird surging like breaks being taped while coasting on freeway
- Thread starter Fancy
- Start date
Check your wheel bearing.
Yeah, wheel bearing or maybe ball joints?
Rotors out of round, chattering?
1990 will have that weird ABS. You could unplug the wire harness at the computer (it's on the master cylinder) to disable it.
-- A
Rotors out of round, chattering?
1990 will have that weird ABS. You could unplug the wire harness at the computer (it's on the master cylinder) to disable it.
-- A
Sounds like the trans is about to go, same thing happened to me about a year after I purchased my 89 Blazer (planetaries and sprag IIRC).
Irish1941
1/2 ton status
x2 for problem in trans.
To me, sounds like the convertor is kicking in and out of lockup. Mine was doing same thing few months back. I replaced the original solenoid and surge was gone.
To me, sounds like the convertor is kicking in and out of lockup. Mine was doing same thing few months back. I replaced the original solenoid and surge was gone.
Irish1941
1/2 ton status
What do you mean "hear" the diff?
Clunk noise from coast/accelerate?
He means you can "hear the difference". The engine rpm will go up a couple hundred when the lockup is disengaged.
I'm not disagreeing with any other ideas here, but I have heard of a baffle coming loose inside a muffler and causing intermittent restriction. I suppose the same could happen with a catalyst. Also, any chance it's misfiring? Or that the surge is the EGR valve opening and closing?
I'm not disagreeing with any other ideas here, but I have heard of a baffle coming loose inside a muffler and causing intermittent restriction. I suppose the same could happen with a catalyst. Also, any chance it's misfiring? Or that the surge is the EGR valve opening and closing?
Irish1941
1/2 ton status
Ooooohhhh...hear the difference!
Doh!My last one there was hardly any notice in rpm drop. Maybe 50-100 rpm on the tach. It was more of a seat-of-the-pants rapid surging sensation with light throttle/coasting that tipped me off to lockout. Unplugged trans and I knew where to start looking.
thanks guys for the ideas. I just rebuilt the trans and brand new converter in it about 5-10,000 miles ago so i sure hope its not my trans. Could very well be bearings. Im pretty sure there is no RPM difference so im guessing its not lock up. Ill look more into it and get back to you guys thanks again for the ideas.
