Hi guys, my first post, I have been reading through the entire forum looking for a solution for my problem but I had no luck. Hopefully someone has had the same issues. I just purchased a 1997 bonneville non supercharged with 104,000 miles. It seems to have been maintained by the person I bought it from, it has had..

trans filter/flushed
air filter
trans/oil pan gasket
radiator hoses replaced,
looks like it had a replacement coil (one out of three is a gray color, the other 2 are black, hopefully it is for the right car)
I replaced the following when I got it..
spark plugs/wires
fuel filter.

My problem is when I am accelerating anywhere from 30-50mph it randomly sputters, or moves back and forth and is just damn annoying. It has the CEL on and it needs a MAF sensor. I cleaned the sensor, still has the problem, and I also tried unplugging it. It does the same thing. I have only drove the car about 400 miles since I bought it, it has died at random twice during this period, I was driving going about 45mph when it died and then it died once at a stop sign. I am going to buy a new sensor soon but I think this might not fix the problem. It seems like it is changing gears from 2-3 or 3-4 very quickly back and forth, it does not do this all the time. Sometimes I can go a good 5 miles without anything.... I hope someone can give me some kind of advice on something else I should check, or if I do buy a new MAF this will fix the sputtering/jumping feel. Otherwise the car is excellent, idles fine, is very quiet and smooth.


Thanks for taking the time to read

The sputtering sounds like a bad fuel injector causing a misfire. The dying at idle or while driving sounds like a crank shaft position sensor. Get the car scanned for DTC'*.

Will my mechanic see more codes on a different machine than the typical codes the people at autozone find for me? Like right now only the MAF low signal is showing, will my mechanic be able to find out if the fuel injectors/crankshaft position sensor are all working properly with a more sophisticated code reader?

No, I am just looking to see if you have a misfire code.

When my crankshaft position sensor failed:

• driving at highway speed, engine stalled and restarted on its own (feels like the engine stumbled), tachometer dropped down to zero until car was stopped, turned off and restarted
• car died when coming to a stop, started right up
• car wouldn't start, let sit for a few minutes, started right up
• incidents increased in frequency over time

A bad fuel injector would probable throw a DTC.

Thanks for your advice. I will have it scanned in the next few days. It is all totally new to me, as my other two cars are a Geo metro and Daewoo Lanos. Totally different dimension with this big American car with speed and buttons. Even with the sputtering once in a while, for a handicapped car, it is the most comfortable and fastest ride I have ever been in. And it was only $500, cant beat it!

A basic scan, such as what they will do at Autozone, will be fine. Come back and tell us what the codes are.

You take that back!

Seriously though, change your crankshaft position sensor, codes or not. It sounds like you're going through what I went through on my '97. It wasn't until a few months later when I would get the first DTC code about the KPS going.

Any shop will do it for around $200. Or you can do it yourself in an hour or less for $25 (plus deposit to rent a harmonic balancer puller from Autozone). There'* a million threads on here about it; not sure if there'* a step-by-step yet.

And as they say around here, put the year and make of your car into your signature. It helps us out a lot.

Here'* a whole list of things to check with the MAF https://www.gmforum.com/t284077/#post1390963

I bet all the guys think I like being difficult. Ready set...I don't think it'* a crankshaft sensor at this point. Try this if you are holding off on teh maf for a little bit. Unplug it, drive the car. It'll take a bit to adjust to running off the tables of data instead of actual airflow data. Once it does, it should run pretty good and most likely not stall.

Bad maf readings can do all sorts of craziness. When I VE tune my car...it stalls at the screwiest times.

Ok, I will drive it about 100 miles today with it unplugged. I didnt have it unplugged long before because I didnt see results right away. I guess it needs a while. Ill be back!