95 ssei stalling after water pump replacement

First let me say this is a great forum!

I put a new water pump in my 95 SSEI the other day and now the car stalls everyday. This only occurs right at the initial start-up. The first day it was 1 time, yesterday it was 6 times. The idle will rise and fall and then it will cut out. Today I drove my wife to work and it started and ran fine but just as I was leaving the driveway I think it stumbled once and the check engine light came on. I found someone to pull the codes from the OBD computer and they found 2 events.
1- VAT fuel control???
2- MAF sensor
The guy that scanned it wiggled the wires on the MAF sensor. He also knocked on it with a screwdriver handle. He said that if they are bad that this will sometimes cause the engine to stumble. He also noticed that the air inlet pipe where the MAF is located was loose. He tightened the clamp and said that would probably cause the problem. Of course since I just changed the water pump and then this started happening he theorized that when I jacked the engine up (to remove front engine mount during water pump job) I caused this to leak and let additional air in.
Does this sound right? Any other suggestions if the problem persist?

BTW- This only happens after the car has been setting overnight or all day.

Thanks,
Rob

What was they actual code numbers? If the air leak was before the MAF sensor it doesn't make a lot of sense. The MAF meters the air entering the engine. If it is after the sensor then the engine would bring in air that wasn't metered and the car probably wouldn't run at all or run poor all the time. Try and get the code numbers and post them.

The mechanic used a Autoxray scanner. I am not aware that it actually had a code. It read out text on screen.
The supposed leak was before the sensor. It was right where the hose hooks to the throttle body.

you may have gotten coolant in the crank sensor and it's shorting out. Coolant is electrically conductive (much more so than water) and may be causing your problem. Take the crank sensor plug loose, and clean it out with brake parts cleaner and then hook it back up.

you may have gotten coolant in the crank sensor and it's shorting out. Coolant is electrically conductive (much more so than water) and may be causing your problem. Take the crank sensor plug loose, and clean it out with brake parts cleaner and then hook it back up.


Ok...I will try that. Is the plug easy to get at w/o harmonic balancer removed?

Thanks,
Rob

I have just started the car to back it out of the garage so I can clean the plug on the crack position sensor. The car idled eratically and then stalled. I started it again and it stumbled and then smoothed out an stayed running. What I did notice is that it smelled like it is running extremly rich. As I stated in my first post one of the codes that was pulled was for the MAF sensor. If this sensor is not metoring correctly and thinks there is more air than there really is won't it supply to much fuel?

Thanks Again,
Rob

That could cause the problem. I just had a MAF go bad on a 98 Grand Prix. It ran for a while, blew black smoke. The computer thought it was metering -300 g/s of air so it was pouring fuel in.

I checked the connector for the "crank position sensor" and found it to have a seal that was intact and no evidence of coolant on the inside. The outside was stained from coolant but the wires looked good. I also cleaned the MAF sensor with contact cleaner.

When I started the car this morning it turned over, started and then immediatly stalled about a dozen times. Then it ran perfect. I went back to the mechanic who pulled the codes for me the other day and had him pull them again. There were 3 trouble codes.

1) P0101
2) P1626
3) P1629

I am stumpped. Any ideas?

Thanks,
Rob

P0101 is a MAF code, I'm thinking the other 2 are as well. If no one has replied by tomorrow I'll post what I find in the morning. Probably going to have to change the MAF. Actually when I had that problem with the Grand Prix's MAF (it's supercharged also) the car ran better without the MAF connected at all because it went to a preset number "limp mode"
I wrote the code numbers down and will post tomorrow.

P0101 is a MAF code, I'm thinking the other 2 are as well. If no one has replied by tomorrow I'll post what I find in the morning. Probably going to have to change the MAF.

86TATpi,

Thanks for hanging in there with me on this.

P1626 was theft deterent fuel enable and 1629 was theft deterent crank signal wrong frequency or something close to that.

Thanks Again,
Rob

No problem, here's what I found.

P0101: No signal from MAF or low g/s.
With the sensor disconnected, turn the ignition on it doesn't need to be running. Measure voltage at terminal A and ground. Terminal A is the yellow wire. There should be 4-6 volts. Use a test light for terminals B (black and white) and terminal C (pink). The test light should stay on. If the wiring is fine, the connector or sensor is bad. If they don't work, then you have bad wiring or PCM.

P1626: sets when if the fuel enable signal is lost after the engine has started.
P1629: the fuel enable signal is not present during crank.

I'm not sure if a loose wire on the bad of the ignition switch would cause this. I'll try and type what the flow chart basically has.

1. Does vehicle crank?
2. Ignition "off" disconnect the theft deterrent module. Turn the ignition "on". Measure voltage between theft deterrent module harness connector terminal "A3" and ground. (A3 is the dark blue wire). It should measure 4-6 volts. If it doesn't the wire may be shorted to the PCM or faulty PCM. If it does measure 4-6 volts.
3. Ignition "off" reconnect theft deterrent module. Ignition "on" measure dc frequency between theft deterrent module connector terminal "A3" and ground. Frequency should measure 40-60 Hertz. If it doesn't check for bad connection at theft deterrent module and "A3" If that's ok, then it's a faulty theft deterrent module. If it does measure 40-60 Hertz.
4. Ignition "off" clear the DTCs by disconnecting the PCM battery feed for 10 seconds. Attempt to start the vehicle. Does it start? If it does, it may be intermittent. If it doesn't start, check for poor connection at the pcm terminal WD14 (The dark blue wire again) If it's ok, the PCM is faulty.

I'm not sure how much you can do yourself. I hope it helps. The theft deterrent module is located behind the top RH side of the instrument panel. It is above the PCM. You may have to pull the instrument panel off to get to it. If you need more info let me know. Try the MAF first and see if it runs.

I checked MAF wiring per above directions...ok
replaced MAF sensor.
The car starts without throwing a code but the idle is a little high at first. When driving the car surges occationally. It seems that it is throttle position or rpm related. (push pedal down further and it stops) I have tried to drive the car in the range where it studders the most in hopes of getting a check engine light. It isn't happening.
Any suggestions?

Thanks,
Rob