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1999 Buick Century Repair Question


Topics covered: Sensor, Coolant, Battery.
Mileage: 170,000 miles.

Asked on September 24, 2012

High idle issue and intermittant shifting cause IAC, TPS?

Replied on September 26, 2012

Will let you know definitely tomorrow. The PVC connector end looks like a plug boot cover that was put at the end of the tube. It also causes a whistling sound I think the boot that was used I too soft and causes the "cap" to collapse hense the horrible sound in the engine compartment.

Tiny Response from dlvaughn1963
2 questions asked
Replied on September 26, 2012

That sounds like a good start keep me posted.

Tiny Answered by saturntech9 (expert)
23,180 answers provided
Replied on September 27, 2012

Replaced PVC tube, idle is much better. Computer must still be learning fuel mixtures and shifting is much better with some sluggishness. The old hose was loose on the vac connector from the vap solenoid. Will see how things work out after a few trips. I do still wonder about the IAC. the maintenance manual shows the removed position of the actuator so ill look into that next b

Tiny Response from dlvaughn1963
2 questions asked

Replied on September 27, 2012

Try taking the negative battery cable off for about a min then put it back on and see how it works then.

Tiny Answered by saturntech9 (expert)
23,180 answers provided
Replied on September 27, 2012

Codes cleared still high. Will look at possible bad IAC

Tiny Response from dlvaughn1963
2 questions asked
Replied on September 27, 2012

Have we looked for more vacuum leaks?What about the coolant temp sensor have.we looked at that yet?

Tiny Answered by saturntech9 (expert)
23,180 answers provided

Replied on September 28, 2012

Coolant temp is relative to engine performance. The temp at the moment never goes over half way

Tiny Response from dlvaughn1963
2 questions asked
Replied on September 28, 2012

I have seen cars with no symptoms of overheating etc with a failing coolant temp sensor causing a high idle.

Tiny Answered by saturntech9 (expert)
23,180 answers provided
Replied on September 28, 2012

Ok will look at that next

Tiny Response from dlvaughn1963
2 questions asked
Replied on September 28, 2012

The codes did clear when I disconnected battery but did come back. I suspect the bank1 o2 is still bad cause the fuse is again blown. This o2sensor is not easy to get to unless I pull the ignition control module and coils.

Tiny Response from dlvaughn1963
2 questions asked