Helping a neighbor with a SC Buick Regal.
There is 161,000 on the OD.
He has done a good bit of engine maintenance and other items over the years, but has NOT replaced everything.
Right now, the engine will start up normally, without any hesitation, when engine is completely cold
Engine idles smoothly. Upon driving it runs well, but there is slight fluctuation of tachometer, but not all the time.
But I am puzzled by the stock boost gauge. At very slight throttle, it reads boost at halfway on the gauge.
Then, once the car is driven on the open high at speeds over 50mph, the gauge is reading almost full boost even when slightly pressing the accelerator.
The engine seems to be chugging, surging.
The tach does not jump around.
Yesterday, when the car is brought to a stop and left in gear, the engine will just stall. Upon trying to restart, it would do so at the first try.
But now, this morning, after the engine is fully warmed up, the boost gauge continues showing boost at halfway to full boost even when barely touching the gas.
Then, when the engine is shut off, it will not easily restart. Only after 10 tries, it will eventually start again.
I have not yet tried to unplug the MAF sensor when I can will not start. I am aware that when a fully warmed up engine won't restart, it could be the MAF.
But what is causing the factory boost gauge to read 1/2 to full boost?
