2000 Grand Prix 3800 Part Throttle SURGE trans???

**rschap1** · 09-30-2011, 07:09 AM

I finally pulled out the MAF sensor last night. Took it out and un plugged it, started the car like that, and it waivered in RPMs and bogged back and forth slightly for just a few seconds. Then it smoothed out and seemed to run better-smoother. Sprayed down the sensor with CRC Mass Airflow Sensor cleaner and re-installed. Driving to work this morning the surge seemed just about the same. Overall the surging seems to be getting a pinch worse all the time. Next week I will switch rides with the wife and ask her to head to the trans shop and get a scan. I will also get her to bring along some of the info I copied out of here and see what codes are showing and what the trans tech says...I am still hoping not too expensive, fingers crossed anyways.

**rschap1** · 10-04-2011, 01:39 AM

We still have not swapped vehicles so the wife can take the Grand Prix to the trans shop yet, but hopefully real soon.
I was just wondering if all signs do point to the MAF sensor, is there a way to test them other than just replace it?
When the pigtail wiring harness connector was recommended, I looked that all over and it appears fine, but I would hate to buy an expensive sensor when its a bad connection, vise versa, or something else...you know.
Such a thing as a MAF sensor tester or can a multimeter tell you anything??
THANKS once again ! ! ! !

**rschap1** · 10-04-2011, 10:34 AM

Also...
Just in case I do need to buy a sensor...I read that Cardone is a good one?
I see some cheaper ones on Ebay, found Cardones a few places for about $130-$140.
Prices seem to span all the way from $50-$60 up towards $300 almost.
Any actual experience with any of these? Good Bad? Cardone the cheapest "good"?
Probably looking to keep driving the car 6 more months or so if longevity comes in to play...
AGAIN, THANKS ! ! !

**Cutlass** · 10-05-2011, 11:58 AM

MAF sensors are funny things. You definitely want to get a good one. I wouldn't buy a $50 one and I wouldn't be surprised if the Cardone one didn't work to great either. But I don't have experience with the Cardone brand MAF. Maybe you could find a used oem one in a junkyard? And cut the connector off at the same time in case you need it.

oh and BTW, there isn't a good way to test them other then datalogging with a scan tool or a tuning software, like HPtuners.

**bstuby** · 10-05-2011, 08:41 PM

Can't really speak to well for the cardone ones either. I put a BWD in mine, actually put 2 in. First one had a defect I guess, because it ran worse than before. Took it back and they exchanged it for a different one. Haven't had any problems with it yet. Been on the car for about a year or more. The BWD's are cheaper than cardone, but there reaman's, so there is a chance to get a shitty one

**rschap1** · 10-06-2011, 01:45 AM

Wife will be taking the car in for scan later today. Find out some more soon...

**rschap1** · 10-07-2011, 06:45 AM

Trans shop said no transmission codes shown

They recommended replacing the MAF sensor "pigtail" connector, then the sensor itself.
The wife wrote down MAS circuit fault, I think that she meant MAF.
Planing on looking at the connectors, wiring and connections this weekend.
If I gotta, I see NAPA listed a connector (pic).
Then shopping for a sensor if unable to fix the old, or the new doesn't help.
Still cannot believe the range of prices on sensors. Autozone and NAPA each have some listed for $140 or so.
May go that route just because if I do drop it in and its a bad sensor off the get go, I should be warrantied. Of course, hopefully. We'll see...I got a busy weekend of learning to MIG weld aluminum, kid's football, neice's b-day party, assembling new grill, ah, you get the idea.
Sorry to bore yas, but I will try and tell results since you all been helping so much!

**Smittro** · 10-10-2011, 12:07 PM

**rschap1** · 10-11-2011, 01:48 AM

Looked the connector and wiring over last night.
Sprayed contact cleaner on the MAF sensor's "prongs" and into the connections of the weathertite plug end.
Same results as I drove in this morning.
Thinking I am going to try an Ebay $60 sensor...Autozone and NAPA are both about $100 more, so I may take a chance and see how it goes.
If that doesn't get it, I may replace the wiring connector/pigtail harness from NAPA $31.49. Looks like those have about 6-8" of wiring attached. I did not see any thing wrong looking but I guess IF the Ebay sensor doesn't fix it, that would be my last option.

**bstuby** · 10-11-2011, 07:55 PM

What kind of condition is you o2 sensors and cat's in? You could have a o2 sensor failing, they cause all sorts of stuff to go wrong when they do. Including a screwing MAF.

**rschap1** · 10-12-2011, 01:57 AM

Replaced the cat with a Magna Flow just about a year ago. It was "clogged" and throwing its own codes then.
I replaced both O2 sensors before that just to make sure that was not the trouble.
Wish I would have just bit the bullet earlier and did the cat. I kinda feared replacing it, but that went WAY easier and cheaper than I had imagined. Got the "direct fit" cat for $120. Then sold the old one to a recycler on Craigs List for $60. It was not a perfect fit. The downstream O2 sensor is aimed at the passenger's side of the car instead of straight up. Obviously it was cheaper and easier for them to not put a "dip" in the pipe. I had to trim the heat sheild a lil', and used a worm gear hose clamp around the rubber o-ring donut mount to pull it closer to driver's side. For a total of $60 maybe a 1/2 hour to hour install, I was happy enough. It did fix the code where the O2 sensors did not. So anyways... those are fairly fresh compared with the rest of the car.

**rschap1** · 10-14-2011, 08:48 AM

USPS shows that the new sensor was to be delivered today.
Looks like tonight I will be doing a couple oil changes and then install that.
FINGERS CROSSED!!!

**bstuby** · 10-14-2011, 11:21 AM

Just curious... did you post this problem on grandprixforums.net? You would get tons of help is you posted this in the trans section.

**cammed goat** · 10-14-2011, 03:34 PM

Let us know what happens OP.

**rschap1** · 10-15-2011, 06:17 AM

Dropped the new Ebay MAF sensor in last night after doing oil change.
Drove to the gym this morning and was not 100% right off and I worried, but the more I drove the better it acted.
On trip home NO more surge

I think I will unhook the battery for a few hours, and let it start from scratch...
It was a real treat no chugging

Hopefully that was it.

I did post all of this initially on the Grand Prix site. Did not get too much back. Sure not as much here.
I will post results there soon, just to share.

THANKS again to everyone here BIG HELP ! ! !

**Cutlass** · 10-15-2011, 04:20 PM

That's great news. It may take a few days of driving for the Fuel Trims to relearn but sounds like its already getting better!!

**rschap1** · 10-17-2011, 01:39 AM

WHat a dream driving into work today compared to what it was with old MAF sensor.
No chug, surge, hesitation, or stumbling.
I got pretty used to feathering the throttle and trying to jump past the bad spots

Wife drove a short trip yesterday, stopped to shop, then when driving home said the SES light came on.
I again un hooked the battery and let it sit for about a half hour before reconnecting it.
I am guessing (HOPING) that just re learning set something off and it will be OK.
I did not see any light today and my ride is 60 miles mostly highway.
If I see it on as I head home I will stop into Autozone and see if they can give me a code.
It sure did run and drive LOTS better this morning though. Wife said it drove fine for her too, just the light on.
THANKS again for all the info, and I will post a link to this thread today at the Grand Prix forums

**cammed goat** · 10-17-2011, 12:39 PM

Is the intake bellows loose at all? That could trip a light, if it's not the code already stored in the PCM.

**rschap1** · 10-18-2011, 02:09 AM

DARN IT!!
Thought I had it made yesterday. Car runs GREAT. Much better throttle response. I like it!!
BUT after about 200 miles of driving, the SERVICE ENGINE SOON light lit again

Went to Autozone and got it scanned. I was told it showed P0171.
Said the front bank of cylinders was showing a lean condition.
Said that it could be MAF sensor, fuel pressure, O2 sensor, ignition misfire, or fuel injector trouble...
Wondering what is best to do next????
I never thought that there was an O2 sensor per bank, I had replaced the rear near firewall and the downstream one.
The front one (which I never even noticed before and it was never mentioned, but I guess if it can throw codes specific to front and/or rear there must be 2) is original to the car.
Wondering if un hooking battery, touching positive and negative cables together and doing that "reset" is worthwhile or not...?
Good or bad idea? Would doing this help clear trouble codes or get things back on track?
OR does it sound like there is another real trouble...?
MAF sensor (NEW) suspect? I am thinking that both front and rear codes would show then, right?
AGAIN THANKS ! ! !