05 park av

Yesterday the car started cutting out on the way to work. Like slight temporary power losses. When I left work it would start good but would not have enough power to move the car and would die as soon as put in drive. After a dozen times starting it I finally got it to crawl out of the parking lot onto the street. After going a half block it started sputtering slowly picking up speed till it was running fairly normal. After going thru 2 stop signs and a red light safely. Very little traffic. Got onto the freeway and had no problem on the 30 mile ride home. The last half mile I stepped it to the boards and it picked up perfectly. Home sitting at a idle it would barely keep running speeding up and down on idle.

My buddy has a tester. The check engine light is on. Reading up it seems this could be a Symptoms of a Bad or Failing Idle Air Control Valve.

Any other thoughts

If you were stepping on the accelerator and engine was still running rough, it’s not the IAC valve.

A bad crank sensor can cause what you describe.

Tester

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Another idea, the IAC control is ok, but throttle valve itself is sticking inside the throttle body.

When I stepped down later on it ran perfectly.

Thanks guys. Hopefully within a week or so I can get my buddy to stop over w his tester. I was also thinking could it be a oxygen sensor? Gas cap?

The IAC valve only functions when the accelerator isn’t being depressed. Like idling with your foot on the brake

When stepping on the accelerator, the IAC valve doesn’t come into play.

Tester

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In addition, of course check fuel pressure. It’s Gm. I don’t know if this still uses the maf sensor anymore, but when I had a couple bad mass air flow sensors, it acted just like being starved for fuel. The only time I’ve had an iac issue it was a high idle like a stuck fast idle in the old days.

If just shot gunning replacing parts, crank sensor, clean the maf, check fuel pressure, then shop time. Word of caution, on some Gm like mine, changing the crank sensor is easy but then needs to be synced using a tech 2 device so check the book first.

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Ok thanks. My neon had crank cam sensor problems. I guess the symptoms were somewhat similar but more good on starting out and bad when stepping on it.

His tester should bring that up. It can sit in the shed for now as the winter beater works great.

Soooo what are the codes???

A failing mass air flow sensor can make a vehicle act crazy also…
Sometimes you can unplug the MAF to see if it runs any better, it may not idle unplugged, but you can drive… I have had vehicles towed in and just unplugged the MAF just to be able to drive it around the building and into the shop…

Here are some of the most common symptoms of a faulty mass airflow sensor:

  • The engine is very hard to start or turn over.
  • The engine stalls shortly after starting.
  • The engine hesitates or drags while under load or idle.
  • Hesitation and jerking during acceleration.
  • The engine hiccups.
  • Excessively rich or lean idling.

EDIT: Bing hit reply while I was still typing… lol

I changed a crank s in a 91 lesabre once. Wasn’t to bad. Compared to a neon it’s a lot of work.

Everyone of those apply but hard turning over b

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Must have been the kind mounted by the balancer. The new ones bolt to the engine. Like one bolt easy to get to. I was going to do it until I read the need to use a tech 2 device so had the shop do it.

Now the shop said the have the same device as the dealer and tried two of them and couldn’t get it to communicate either the bcm or whatever. Works fine though. So maybe you can just bolt a new one in. @Tester would know. Just scared me off.

I’ve also tried cleaning the maf but never worked so ended up replacing back when they were $300. A lot cheaper now I think.

All good ideas. The diagnosis and sol’n shouldn’t be overly difficult for a pro mechanic. Hopefully OP will let us know what the cause turns out to be.

I will let you know. Might be a week or so

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Did a code test today.

P0101. Mass or volume circuit range performance problem.

P0107. Manifold Absolute Pressure

Also I noticed a strange occurrence. The battery drained dead the day before I drove it and ran like shit. Thought nothing of it at the time. Charged it drove it no problem. Even yesterday started up turned over fine. Todsy totally dead

So this problem is causing a drain.

Try unplugging the MAF sensor to see if the battery drain goes away.

Tester

Ok. I’ll also try swapping the one from my lesabre. I see this little guy pops out without even needing a wrench.

Should get that done tomorrow

Did u mean MAF OR MAP sensor unplug?

MAF!

Tester

I see. P0101 is the MAF.

THANK YOU