One more strange anomaly: Car randomly dies once while cruising

[John Larkin]

This has happened to me twice. I get it out cruising and all is well. About 5 miles into the cruise, it starts to buck and stumble and dies. There is no warning and I haven't been watching Scanmaster or logging. I pull over, restart and all is well from there on out. One thing I noticed afterward that watching the voltage at steady cruise the alternator is putting out 12.7 - 13.3 volts. It does go up when accellerating and never drops below 12.7 that I have noticed.

Just strange. Otherwise there are no issues other than my emissions quest at the moment.

Insight appreciated.

 

[BEATAV8]

Have a close look at the crank sensor, see if there's any damage due to contact with the reluctor wheel. Can be hard to see sometimes.

grab a spare just in case, found some new AC Delco parts on amazon a few weeks ago.

 

[whitehot1]

The one and only time my car did that bucking thing. It was caused by one of the ground wires on the back of the head. I was so excited about finding and fixing the problem so it wouldn't be trying to buck me out of the seat anymore. That i didn't take the time to trace out the ground wire to see where it went to.

 

[John Larkin]

I will check both of those. I am draining coolant today for the stat tomorrow. I will be under the hood anyhow so it's something good to do in the shade in front of a fan, hot today! Thanks!

 

[John Larkin]

The crank sensor looked good. No wear on the reluctor rings other than a bit shiny on one of the three at either end. I was able to wrap a piece of thick notecard paper around one and it rotated through the sensor no problem so I would say the clearance is fine. I did clean off quite a bit of undercoating from two of them and sprayed out the sensor with electric contact aerosol.

Just for fun I pulled the cam sensor cap. All was clean inside, the ring was held in place by the tab and not swiveling around. The tab was very small though, maybe 1/32" but seemed to be enough to hold it in place.

I have not tackled the ground wires yet. I have alot off the front of the car and need to get that back on before getting too many parts strewn around.

I got the thermostat housing out with no damage other than it bent a little but a large socket and a few firm whacks in my vise and it is straight again. Took a while though to remove. A 23mm socket inside the neck + an extension and some working it up and down along with some gentle tapping with a screwdriver in front of the O-ring did the trick. O-ring even came out nice and pliable.

 

[SHADOWII]

Does the bucking happen at a certain speed? Maybe l/u solenoid getting weak or loose wiring/connector.
Ignition module overheating. Or maf starting to give up the ghost! If you recently cleaned you K&N, too much oiling can result in damage to the maf if the oil makes its way to the maf sensor.

 

[HighMileage]

Check the orange ECM wire behind the battery. It plugs into itself back there.

Mine was pushed together but not clicked. Was making an intermittent quitting problem.

 

[GNRick]

The crank sensor might look good but could still be bad. I was getting a hesitation at 40 mph. A new crank sensor fixed it.

 

[John Larkin]

Can I replace the sensor without removing the bracket? That thing is a PIA. I have to take off the IC bracket minimum. I could but heck.....

I put a new Bosch O2 sensor in tonight. That was an ass whipping as well. I had to remove the hard heater line hose to the water pump, the turbo shield and the wastegate assembly to get the right angle on it to get it threaded. Someone else suggested the balancer could be loose. Pried on it a bit with a small crowbar and it only moved as much as the thrust bearing from the feel.

Back of head grounds look good and tight, not corroded.

The thermostat was delayed a day by the USPS so it will be tomorrow night before I have it buttoned back up and running.

 

[whitehot1]

Can I replace the sensor without removing the bracket? That thing is a PIA. I have to take off the IC bracket minimum. I could but heck.....

I put a new Bosch O2 sensor in tonight. That was an ass whipping as well. I had to remove the hard heater line hose to the water pump, the turbo shield and the wastegate assembly to get the right angle on it to get it threaded. Someone else suggested the balancer could be loose. Pried on it a bit with a small crowbar and it only moved as much as the thrust bearing from the feel.

Back of head grounds look good and tight, not corroded.

The thermostat was delayed a day by the USPS so it will be tomorrow night before I have it buttoned back up and running.

Yes you can replace the crank sensor without removing the bracket.

The Denso o2 sensor is way better than the Bosch. Rockauto.com has the best prices even with shipping cost added.

 

[#1HotRod]

May sound simplistic...but perhaps plugged cat converter? Years ago mine did that about town, then fine awhile. Then on a trip started loosing power, worse & worse. Rented a trailer & brought car home. Someone must have mentioned it to me, but lo & behold when took that puppy off all was fine. 'Course now it has one of those magic units that cannot plug up. Cheap & easy try!

 

[TURBOTIMMER]

Take your serp belt loose and check the crank pulley itself. One of my old high mileage turbo Regals, my balancer bolt worked its way loose. Motor had never been touched and had 175k miles. At cruising speed the balancer would walk out and cause what you're describing. Car would buck it's way to a full stall, shut off, start right back up, and be fine.

 

[John Larkin]

I'll loosen the belt tomorrow night and see if it has any movement in it. I don't have to remove the IC fan to check do I?

 

[SHADOWII]

I'll loosen the belt tomorrow night and see if it has any movement in it. I don't have to remove the IC fan to check do I?

No, just take care not to damage it.

 

[John Larkin]

Winner winner chicken dinner. The balancer is a little loose. Loosened the belt this morning and the balancer has a little slack in it, not much though. Removed the SLIC and fan just now but I have to get ready for work so tonight it's torque time and I guess I need to recheck the sensor clearance afterward. I have to say it was less worrisome wrenching 10 years ago...I have to balance how much I contort myself with how many Advil I take.

 

[TURBOTIMMER]

That bolt needs torqued to like 220 ft lbs. wouldn't hurt to put a couple drops of locktite on it either.

Glad you found the problem.

 

[John Larkin]

I torqued it just now, 219. Tight as Dick's hatband.

 

[John Larkin]

Seems to have worked. Just went 22 miles roundtrip and no stumble. Today might just be a good day. And I passed emissions too.

 

[#1HotRod]

... And I passed emissions too.

Now THAT'S a big deal !

 

[SHADOWII]

Congratulations!