2000 Grand Prix 3800 Part Throttle SURGE trans???

**BillBoost37** · 10-25-2011

If you read up on the code. Say at Gearchatter.com you'll find out tons of cool stuff and it'll make much more sense.

**rschap1** · 10-26-2011

Originally Posted by BillBoost37

If you read up on the code. Say at Gearchatter.com you'll find out tons of cool stuff and it'll make much more sense.

I gotta say THANKS
I have been reading through search results for the "P0171" and there has been plenty.
I learned quite a bit here and at gearchatter about how the engine control works and adjusts for my car. Really wish that I had a scan tool now too.
I appreciate the way that I was lead towards the resources too. Like teaching me to fish rather than just throwing a fish towards me, as the old sayings go

I am guessing that when I replaced the old MAF sensor with new and did not disconnect the battery, the old "trims" were in place. These were created with the faulty sensors input and conflicted with what was needed with the new proper sensor. Then I did clear the codes and trims when I pulled and crossed the cables. Again, now running from the baseline, trims were needed but not in place so SES light went back on. A few rides/cycles let the control adjust to the new sensor and everything has now meshed.
At least that is my "all is good" wishful theory.
I hope that sounds plausible

I hope that I am interpreting all the threads properly.
If not I appreciate any more clues that I may have walked right past.

BIG THANKS ! ! ! and PLEASE feel free to let me know if I totally missed the point and am all wet. Won't be the first (or last) time.

**BillBoost37** · 10-26-2011

Glad that approach worked for you. It seemed like you wanted to learn and may have wanted to be directed where to find the info instead of handing it to you.

There's a couple of places I do this.. P0171 can be a pain for a lot of people. I've tried to list out the very common things, but once in a while..it's not the easy fix. That's when reading up and interpreting what you may not have fully written out is key.

Once I learn how a code is triggered, I learn a lot more about what's going on and understand so much better how all the systems/codes mesh.

Take a P0401 EGR insufficient flow for example. Hit that up on Gearchatter and you'll find...most likely it's not a blocked EGR. It's not usually a non-functioning one either, cause that would toss more/other codes. While the code is named EGR, it's often a bad map sensor.

**rschap1** · 10-25-2011

Its been a few days and I have not seen the replacment sensor yet, BUT
It has been 5 days and over 400+ miles w/o the SES light on and still running good.
Is it possible it just takes a lil' while for the controller to adjust to the new sensor?
I had wondered why a lean alarm too? Wouldn't it, shouldn't it just richen the mix?
I am a little puzzled (as usual) but wondering if all is good now, or not?
Should I mess with it,or leave it alone?
The SES light did go off by itself while driving, it wasn't me pulling the battery cables again or anything...did it just "fix itself" I mean adjust for the new MAF sensor signal??

THANKS for everything

**rschap1** · 10-25-2011

Sounds like I would be WAY better of with my own scanner

Unfortunatley I do not have on.
Gear Chatter looks like a pretty helpful site. THANKS
Wondering if the car is running in open or closed loop now...

**rschap1** · 10-27-2011

This has shown me the value of a scan tool too... Another poster on LS1 said I could get a cheap tool for $20. I was under the impression that it was $250-$350 for a worth while scanner, but it did get me thinking that maybe I should shop for one at least if there are any out the that cheap, so I posted the questions below:
"Well I gotta ask now...
Probably should be a whole new thread but...
suggestions for a cheap scan tool?
Good, bad, what to look for, what to avoid?
Ebay searched and saw some OBD2 (I am guessing that is the correct set up, right?) to USB cables and interfaces.
Using a laptop easier or better? worse? Also saw some adapters, mostly wireless, to ipods and iphones. I could steal my kids ipod I guess. Good bad?
I hate to go too cheap really, but that is what I am all about, my old Ford tool had me counting long bleeps and short flashes then referencing a list. Never was real sure if I had missed a beat or what was going on.
I don't think that I need the fanciest or most expensive detailed unit out there, but it would be nice to see a read out not count long and short led blips.
Thanks "

Any other input would be appreciated as I search for one.
THANKS

**BillBoost37** · 10-27-2011

There's a bunch of different choices..that's for sure. Your choice on what you do.

I most commonly look for
Code reading and clearing
TPS %
Misfires by cylinder number
Trans temp
Trans gear
RPM
Coolant temp
Maybe trans TCC duty cycle
KR

There's really not a ton that you need from it....but KR is key.

**rschap1** · 11-03-2011

Well, back to AZ...

Got a refund from Ebay for the cheap MAF sensor.
The last couple of days things have gotten a little worse.
The SES light has been intermitten. On for a day and a half, off for the next day or 2.
Yesterday and this morning the surge hit a little bit again.
AND for the first time since new sensor, I had the car idling for about 10 minutes while chit chatting with a neighbor. Car got warm and then idle speed increased.
It idled 500-600 rpms more than usual and when I went to pump the accelerator it stayed high and took 15-20 seconds to slow to normal. Kinda scary. It reved more than it should have, like a sticky gas pedal. Thinking that may have been 1st period of extended idle with new sensor it things went wacky.

Plan is to hit AZ again tonight, get scanned if light is still on, if same error P0171, I am going to take my refund and put it towards one of their refurbished Cardone models and try that. AGAIN fingers crossed! I will ask and price what they sell for scan tools too.

**rschap1** · 11-04-2011

Same code was shown, picked up their refurbished MAF sensor and saw all Actron scanners at Autozone.
There were 5 or 6 models from $59 to 299.
Didn't look to closely at the features tried to hurry through there.
$139 for the sensor and a $87 core charge...makes me wonder what they do to refurbish these...?
We'll see how it works when I install this evening. Guessing it would be best to unhook the battery cable, cross them, and then install the new sensor rather than just unplug the old and plug in the new like I did before. Start at the baseling...right?

**BillBoost37** · 11-04-2011

It won't hurt. Like you say..it'll reset things.

On maf's, they probably put them into a quick test to see if the wire is broken or something along those lines.

When I read up on maf codes etc. It's cool that the sensor is read as a power used to maintain a temperature of that heating element wire that we see when we look at the maf.

**rschap1** · 11-04-2011

Thanks !

**talladam** · 11-06-2011

Hate to hijack but I'm experiencing similar issues here.
00GT with 52k miles. Engine RPM flutters up and down (200-600 rpm) after shifting into 3rd and 4th gear under light throttle. Issue seems to be gone during steady cruise speeds. Seems to be worse when outside temps are below 50. Had a scanner on it the other day and saw that timing was 14-18 when surging/fluttering started, returns to 34-36 during cruise.

Brand New Delco MAF has 300 miles on it, Prestolite Wires and NGK Iridium IX Plugs have 1000 miles on them. Wires aren't touching the o2 wiring. TPS is new.

Fuel filter, Trans fluid & filter changed 1000 miles ago.

Any suggestions?

Adam

**rschap1** · 11-07-2011

Have you had it scanned for any error codes?
It does sound familiar.
My trouble does seem to revolve around the MAF sensor.
Yours is new though...the trans shop that helped me out kept reminding me (actually my wife so she could tell me) that it could be the wiring or the pigtail for the sensor too. Napa sells that part so it must be common enough for them to offer too. Just a thought, about all I can come up with after reading how many things you have done already.
Good Luck.
I am a couple days into my Autozone Cardone sensor. Runs good again and seems OK. Time will tell. I did remove and cross the battery cables. No SES light, no surge, and running good. Some kinda noise the wife noticed the other day, sounded like something rubbing on the tire when turning hard right...think I may have misplaced a plastic splash shield or something

I dropped a little 5/16" socket when replacing the battery cables and had to feel around under the crank pulleys. Hoping that is something simple like that anyways. Fingers crossed again ! ! !

**talladam** · 11-07-2011

I really need to quit posting when I'm tired.

MAF pigtail has been replaced, no ses lights or codes thrown.

**BillBoost37** · 11-07-2011

Tall.. Replace the bosch plugs with a non-platinum, non bosch plug. Autolite, Delco or NGK are the favorites.

I'd say you'll have a 90% chance that fixes it. Reason being is plats don't do well in a waste spark setup like ours. And Bosch plugs for some reason (like thier 02's) don't last very long in our cars.

**rschap1** · 11-07-2011

Personally, I avoid Bosch stuff for a whole different reason...they bought the company I worked 13 years for then moved it out of state

We were their competion originally and the could not beat us

But I had their O2 sensors recomended and put those in prior to replacing my cat. Hopefully they hold out for a while yet. I had never heard that about those or the plugs. I have had the best luck with Autolite plugs so I try REAL hard to use those in everything and anything I can. Even my small engines etc. NGKs for some of my 2 strokes (jet skis, outboard, and snowmobile) due to availabilty usually. I learned more new stuff today...avoid Bosch plugs and O2 sensors in the gP. THANKS again !!!