help stalling

[zadam123]

for 2 days now after driving for about an hr. with no problems my car suddenly starts stalling out when i let go of the gas or the idel gets low. if i try to give it to much gass it studders then takes off. any ideas what this is? Got an error code P0101 was told this is a mas air flow center could this ibe the problem and how much should it be to fix

[etlsport]

search fuel pressure regulator or intake manifold... could be either... possibly egr

[deermagnet]

Adam, this is from the '99 VX repair CD.

http://www.drivehq.com/file/df.aspx/publish/mgpa/img/stall1.gif
http://www.drivehq.com/file/df.aspx/publish/mgpa/img/stall2.gif
http://www.drivehq.com/file/df.aspx/publish/mgpa/img/stall3.gif

Mark

[tom4bren]

When I had a similar problem, the shop replaced my air filter & cleaned the MAS. Problem solved.

[Dino]

I pulled the Idle Air Control Valve on mine, cleaned the crusty gunk off from it, gave it a small shot of PB Blaster, reinstalled it and no idle problems since. :cool:

[mdwyer]

I pulled the Idle Air Control Valve on mine, cleaned the crusty gunk off from it...

I did the same thing, and that fixed the problems for almost a year. However, it stalled at a stoplight on me a few weekends ago. I'm told that my EGR is almost clogged, so I'll probably try replacing that, next.

[deermagnet]

I pulled the Idle Air Control Valve on mine, cleaned the crusty gunk off from it, gave it a small shot of PB Blaster, reinstalled it and no idle problems since. :cool:

Good idea there, Dino. I pulled mine after 160K miles and it was very dirty. It's on the upper left side of the throttle body when facing the engine. The manual says don't immerse the valve in solvent and don't apply so much pressure to the pintle that it moves. Just spray the pintle and spring with carb cleaner and use a tooth brush. Also clean out the area where the valve sits.

Another easy cleaning job to keep everything running right.

Mark

[Tone]

Let's see - he got a MAS code and everyone is telling him to check other things? Aftermarket airfilter? Recently re-oiled? Dirty?

New MAS is probably around $150 (MBs were $500 I recently found out...) I may have a spare laying around - email me.

P0101 OBD-II Trouble Code

Technical Description

Mass Air Flow (MAF) Circuit Range/Performance Problem

Basically this means that there is a problem with the Mass Air Flow (MAF) sensor or circuit. The PCM detects that the actual MAF sensor frequency signal is not within a predetermined range of the calculated MAF value for more than 4.0 seconds.

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:

Inspect for the following conditions:
An incorrectly routed harness--Inspect the harness of the MAF sensor in order to verify that it is not routed too close to the following components:
- The secondary ignition wires or coils
- Any solenoids
- Any relays
- Any motors
A low minimum air rate through the sensor bore may cause this DTC to set at idle or during deceleration. Inspect for any vacuum leaks downstream of the MAF sensor.
A wide open throttle (WOT) acceleration from a stop should cause the MAF sensor g/s display on the scan tool to increase rapidly. This increase should be from 6-12 g/s at idle to 230 g/s or more at the time of the 1-2 shift. If the increase is not observed, inspect for a restriction in the induction system or the exhaust system.
The barometric pressure (BARO) that is used in order to calculate the predicted MAF value is initially based on the MAP sensor at key ON.
When the engine is running the MAP sensor value is continually updated near WOT. A skewed MAP sensor will cause the calculated MAF value to be inaccurate. The value shown for the MAP sensor display varies with the altitude. With the ignition ON and the engine OFF, 103 kPa is the approximate value near sea level. This value will decrease by approximately 3 kPa for every 305 meters (1,000 feet) of altitude.
A high resistance on the ground circuit of the MAP sensor can cause this DTC to set.
Any loss of vacuum to the MAP sensor can cause this DTC to set.
If you suspect the condition may be related to aftermarket accessories, refer to Checking Aftermarket Accessories in Wiring Systems.

[deermagnet]

Tone, he edited in the code after some of the replies. I asked him what code he was getting in another thread and he posted the code here in this thread.

http://www.vehicross.info/forums/showthread.php?t=12188

Mark

[zadam123]

ok i had to change the mas and then he said my iac was no good so total cost me $400. runs good now but i still have a p440 code. I was told it may be my egr valve but not sure. he said to pinpoint the problem it will cost 275 to run full diagnostic? does that sound right?

[Dare2Dream]

That would be an expensive diagnosis. If you have time and are mechanically inclined, then perhaps you should try to find the problem yourself with help from here. Otherwise, find a reputable shop that charges a decent rate for diagnosing the problem.