20 Most Recent 1999 Pontiac Montana - Page 6 Questions & Answers

Hi there:P0102 - Mass Air Flow (MAF) Circuit Low InputBasically this means that there is a problem with the Mass Air Flow (MAF) sensor or circuit. A more technical description would be that the MAF circuit had lower than expected voltage (air flow). Other MAF sensor circuit DTC trouble codes are P0100, P0101, P0103, and P0104.You will likely not notice any serious drivability problems, although there may be symptoms such as a general decrease in power or sluggishness.A code P0102 may mean that one or more of the following has happened:The MAF may be disconnected, or a wiring connection may be badThe MAF may be dirty or otherwise contaminated (Note: if you use a reusable oiled air filter, be careful not to apply too much oil or that can contaminate the MAF).The MAF sensor may be faultyThe vehicle computer may be faulty (very rare)Possible Solutions:The simplest thing to do is to reset the code and see if it comes back. Then start with the cheapest, easiest repair procedures:Verify that the Mass Air Flow Sensor wiring is connected properly and that there are no broken / frayed wires.Inspect for any air leaks near the MAF sensor.Take the MAF out and clean it using a spray cleaner such as brake cleaner or electrical contact cleaner. Be gentle with the sensor.Check the voltage of the MAF sensor (refer to a repair manual for vehicle specific information)Replace the MAF sensor.P0135 - Oxygen O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)This code refers to the front oxygen sensor on Bank 1. The heated circuit in the oxygen sensor decreases time needed to enter closed loop. As the O2 heater reaches operating temperature, the oxygen sensor responds by switching according to oxygen content of the exhaust surrounding it. The ECM tracks how long it takes for the oxygen sensor to begin switching. It the ECM determines (based on coolant temp) that too much time elapsed before the oxygen sensor began operating properly, it will set P0135.A code P0135 may mean that one or more of the following has happened:O2 Heater element resistance is highInternal short or open in the heater elementO2 heater circuit wiring high resistanceopen or short to ground in the wiring harnessPossible SolutionsRepair short or open or high resistance in wiring harness or harness connectorsReplace oxygen sensor (cannot repair open or short that occurs internally to sensor)P0141 - O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2)This code means that the heated circuit in the oxygen sensor on bank 1 decreases time needed to enter closed loop. As the O2 heater reaches operating temperature, the oxygen sensor responds by switching according to oxygen content of the exhaust surrounding it. The ECM tracks how long it takes for the oxygen sensor to begin switching. It the ECM determines (based on coolant temp) that too much time elapsed before the oxygen sensor began operating properly, it will set P0141. See also: P0135 (Bank 1, Sensor 1).A code P0141 may mean that one or more of the following has happened:open or short to ground in the wiring harnessO2 heater circuit wiring high resistanceO2 heater element resistance is highInternal short or open in the heater elementNote: Typically a failed catalytic converter does not cause this code. You're more likely to see a P0420 code for a failed converter.Possible SolutionsReplace oxygen sensor (cannot repair open or short that occurs internally to sensor)Repair short or open or high resistance in wiring harness or harness connectorsP0443 - Evaporative Emission Control System Purge Control Valve CircuitThe Evaporative Emissions System (EVAP) allows fumes from the gas tank to enter the engine to be burned, rather than vented into the atmosphere as an emission. The purge valve solenoid is supplied switched battery voltage. The ECM controls the valve by operating the ground circuit, opening the purge valve at specific times allowing these gasses to enter the engine. The ECM monitors the ground circuit as well, watching for faults. When the purge solenoid isn't activated, the ECM should see a high voltage on the ground circuit. When the solenoid is activated, the ECM should see the ground voltage pulled low, close to zero. If the ECM doesn't see these expected voltages, or senses an open in the circuit, this code is set.P0443 trouble code symptoms could be just an malfunction indicator lamp (MIL) illumination. There may be no drivability problems at all. But, it's also possible to have a lean condition or a rough running engine if the purge valve is stuck open. Usually though, these symptoms are accompanied by other EVAP codes. Another symptom may be excessive pressure in the gas tank in the form of a "whooshing" sound when the cap is removed, indicating a purge valve that isn't working at all or stuck closed.To cause a P0443, there has to be a problem with the purge control CIRCUIT, not necessarily the valve. Usually they are a unit housing the valve and the solenoid as an assembly. Or it could be comprised of a separate solenoid with vacuum lines to a purge valve. That said, it could be any of the following:Bad purge solenoid (internal short or open)Wiring harness chafing or rubbing another component causing short or open on control circuitConnector worn, broken or shorted due to water intrusionDriver circuit inside powertrain control module (PCM) is badPossible Solutions1. Using a scan tool, command the purge solenoid to activate. Listen or feel for a clicking coming from the purge solenoid. It should click once, or on some models it may click repeatedly.2. If it doesn't click with scan tool activation, unplug the connector and examing the solenoid and connector for damage, water, etc. Then check for battery voltage on the feed wire with the key on. If you have battery voltage, then ground the control side manually using a jumper wire and see if the valve clicks. If it does, then you know the solenoid is working properly but there is a problem with the control circuit. If it doesn't click when you manually ground it, replace the purge solenoid.3. To check for a problem on the control circuit (if the solenoid tests okay and you have voltage to the solenoid) plug the solenoid back in and remove the control circuit (ground) wire from the ECM connector (If you're unsure how to do this, do not attempt). With the ground wire removed from the ECM, turn the key on and then manually ground the Purge valve control wire. The solenoid should click. If it does, then you know there is no problem with the control wire to the solenoid and there is a problem with the ECM purge solenoid driver circuit in the ECM. You'll need a new ECM. However if it doesn't click, then there must be an open in the wiring between the ECM and and the solenoid. You must find it and repair it.Hope helps.

The three front ones are simple and the three back ones are challenging. There are two ways to replacing the rear spark plugs on the Montana.
1. If your arms are long enough and you have longs extensions with a spark plug socket with a swivel build in to it, you can get to the plugs from under the Montana.
2. You can get to the rear plugs buy disconnecting the two dog bone engine mounts in front of the engine and tilting the engine forward. You can do this by placing the parking brakes on and disconnecting the dog bone, once that is done. Place your foot on the brakes and take the parking brakes off and push the Montana forward till the engine tilts forward enough to give you the room you need to get your arms over the top of the engine with the extensions and spark plug socket. Make sure you place the parking brakes back on and put a block at the rear of the engine to ensure the Montana will not move back and cause you to loose your arm or head.
Note that you need to keep the transmission in park when tilting the engine and that your going to have to replace the spark plug wires and do everything by touch to replace the rear spark plugs.
Thank you for using Fixya and use platinum spark plugs to give you 100,000 miles of service. Good luck and be safe.

Have you unplugged the brake switch to see if the problem stops ?

factory defect. replace unit inside tank.

Leaking high pressure hoses mean iminent failure get it replace as sonn as you can

OK I know everyone likes a free answer but unfortuantly something like this requires a fee.

go to radio-code.com

they have a small charge but in depth procedures to retrive code

You should take the belt off and examine it. If that is what was starting to burn, you will have to replace it. And now check all the pulleys to see if one of them has siezed up. Spin every one around by hand, feel for roughness or stiffness, or if it wobbles. If you find one that is siezed, replace it. That is where all the squalling started.

can you jumper the relay or find the red wire by the battery that is nit connected it will have a green connector jump it to positive and see if pump comes on

which oil sending did you change .there is 2 on that motor. 1 is next to the oil filter and the other is in the oil pan next to the oil plug

THE OIL PRESSURE SENDING UNIT IS LOCATED UNDERNEATH THE EXHAUST MANAFOLD IT WILL BE THE ONE CLOSER TO TRANS.

Use a rachet end socket

We have no wiring diagrams here-- as the expertsare at home & have to find those things on their ownJust a chat room

Listen for the fuel pump to come onHave someone at the fuel tank & cycle the key on & offPut a pressure gauge on the motor to test fuel pressure

So have you not checked for fuel pressure and aworking fuel pump?