Codes P0102 and P0442

GJMATTXM

MEMBER
2000 BUICK LESABRE
6 CYL
4WD
AUTOMATIC
165,000 MILES

Rough idle/idle stall.

Stalls when parked.

Coolant is low.

Coolant was flushed and replaced less than a week ago and it's already low.

Small amount of white exhaust smoke (not an excessive amount, but more than normal).

Oil pressure sensor not sensing my oil pressure.

I checked the oil in my car, it's not milky, there is no water getting into the oil. Oil is full and was changed a few weeks ago.

When accelerating from idle, the car hiccups.

Car drives normally with little to no issue when not idle.

The MAF sensor was replaced less than a week ago.

The vehicle is not overheating.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Refill the coolant and see if it does it again. There may have still been air spaces when the system was serviced that required more coolant. The result is the level goes down.

Now, the codes you provided are interesting. The P0102 is related to the mass airflow (MAF) sensor which you have already replaced. The P0442 deals with an engine vacuum leak within the EVAP system. A leak can be causing what you are experiencing by allowing unmetered air to enter the engine. As a result, the MAF could be showing an incorrect reading.

Before jumping into all the diagnostics, which I will be happy to provide if needed, I think we need to first check for a vacuum leak in the system.

Here is a link that explains how to locate and repair one:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If you have already done this, let me know.

Take care and let me know what you find.

Joe