NEED HELP!!! I got a 1999 Bonneville SE, the check engine light started coming on intermittently then the car started stalling at idle after reaching normal temperature. checked for code(s) and I got the following: 1) PO1404 EGR valve stuck open condition 2)PO404 EGR system fault (egr position sensor) 3) PO171 Fuel trim bank one condition 4) PO102 MAP(Man. absolute pressure)/BARO or MAF(Mass Air Flow/VAF(Vane air flow) sensor condition; and 5) PO742 TCC stuck on. I replaced the EGR valve, fixed a vacuum leak, replaced the up-stream oxygen sensor, changed spark plugs and wires, air and gas filter, and PCV valve. Car continue to stalls!! Rechecked for code(s) and now I got three additional codes beside the previous five 1) PO403 EGR system fault (solenoid circuit) 2) PO405 EGR system fault (position sensor voltage too low) and 3) PO122 TP (Throttle Position) sensor. I also noticed that it won't go pass 3500 RPM without stuttering, otherwise it runs smoothly under gas. PLEASE HELP!!!!

Since you did the other work, have you cleared the codes?

The TCC code with stalling makes me think you have a bad TCC solenoid, or other tranny problems. When it stalls coming to a stop, does it feel like a manual trans car stopping without depressing the clutch pedal? If so, TCC solenoid or wiring problems would be my starting point.
Is this a "clean title" car, or does it have a salvage title? Do you know the history of the car? Has it been crashed and repaired, is it a "flood" recovery, etc.?
You certainly have a lot of codes. I would be looking for a botched repair in the main wiring harness if I had no history on the vehicle. Or a "musty", wet smelling odor from the interior, indicating a flood recovery.

No, I did not clear the codes after I did the work

I thought about the TCC being the cause but the car stalls during idle too even without moving it just after it reaches operating temperature and nor does it feel like a manual trans when stopping, I will definitely check the TCC. The car is a "clean title" car, I have had it for the last five years with no problems whatsoever until now.

The first thing to do is to clear the codes. Take it for a drive to get it up to operating temp and then scan the codes again. Report them back here.

I cleared the codes and drove for a while, scaned it again and only got a PO102 Map(Man. absolute pressure)/BARO or MAF(Mass Air Flow)/VAF(Vane Air Flow) sensor condition. So far the car has not stalled but it's getting a little rough idling after just been started.

Thanks myfirstbonnie for your suggestion about clearing the codes, I did and after i scanned it again I only got a PO102 MAP/MAF sensor malfunction

Unplug the MAF and see if it runs any better.

Unplugged MAF and noticed no change, still rough just after start

I suggest removing the TB and cleaning it and the IAC. Clean the MAF using the proper cleaner. You will need a new gasket for the TB and will need to lower the coolant level in the radiator so it is below the level of the TB. The easiest way to do this is to siphon it out of the radiator.

Hi guys! It's been a while since my last post but something came up and didn't have a chance to work on my car. To update you the car still has the same problem, still giving me a code PO102 (MAF). I purchased the OBDLink SX scan tool and pulled out the freeze frame, I then erased and cleared the code, started the car and the code came back almost immediately, I again pulled out the freeze frame datas, I did this twice. following are the datas that I got: FREEZE FRAME DTC PO102 TEST 1 TEST 2 TEST 3
FUEL SYSTEM STATUS Closed-Loop using Oxygen sensor
CALCULATED LOAD VALUE 0.39 0.39 0.39
ENGINE COOLANT TEMPERATURE 195.8 199.4 215.6
SHORT TERM FUEL%TRIM-BANK 1 7.03 -3.12 10.34
LONG TERM FUEL%TRIM-BANK 1 -8.59 -17.97 -14.06
INTAKE MANIFOLD PRSSURE 8.27 4.34 11.75
ENGINE RPM 1049 839 800
VEHICLE SPEED 0 0 0
MASS AIR FLOW RATE 0.16 0.16 0.16
ABSOLUTE THROTTLE POSITION 0.39 0.39 0
I don't know what to make out out of this number, maybe one of you guy could give me an idea of what they mean. Your help is greatly appreciated

If you are getting a 0102 immediately, get a hold of a used maf from a junkyard or get a reman from a local autoparts store. Verify you have 12V. at the maf connector first.