OK I have a 97 Z24 with 102,000 yeah so anyway I bought my car about 9 months ago. 2 months after having it one day my car was idleing all messed up and when i drive, it would hesitate and always feel like its gonna bog out and then the fan came on and a flashing check engine light so i went home and then i changed the spark plugs and boots and still no fixin so i let it sit my friend came over and told me that these kind of cavaliers have injector problems like they might get clogged and he said we can try tapping on them with a flat head screw driver so we tapped on top of them u can see the top of them in between the fuel rail and block so we did some tapping, tapped the first one and no change tapped the second one still no hope then on to the third one BINGO it worked the problem is that every like three days it would go back to crap so i keeped a long flat head with me in my car and maybe few weeks later it went away fro like 6 moths and now its back so I tried tapping my injectors again and no hope at all so i will try to see if I can change the fuel filter and try to get a full tank of gas and pour a thing of injector cleaner in my tank then ill try tapping my injectors again and see if it will work if it dosent work work IM gonna take them out and clean them at least i know that injector # 3 was the bad one it the beginning so if u guys are have my same problem just take a flat head and start tapping on them don't do it extremely hard ether u don't wanna break one. If u had this same problem and fixed it tell us all cause there is a few of us with this same problem THANKS.

ok i have the same problem but i have a 03 cav ecotec 45,000miles,i changed the spark plugs and added fuel injector cleaner and still does it. I'll try it, even though mine is not the same engine.

zlr ecotec wrote:ok i have the same problem but i have a 03 cav ecotec 45,000miles,i changed the spark plugs and added fuel injector cleaner and still does it. I'll try it, even though mine is not the same engine.

well i hope u find out the problem man

I have that problem i have posted about it. There is suppose to be a reflash for the cold start which i still have to do on my car. Which i hope helps. I have change plugs, coil packs,fuel filter, spark plugs fuel injector cleaner, IAT change new O2 sensors etc. still the same problem. I don't think it is a fuel pump problem i hope the reflash will help fix the problem when i get a chance to do it.


2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time

Mylife75 wrote:I have that problem i have posted about it. There is suppose to be a reflash for the cold start which i still have to do on my car. Which i hope helps. I have change plugs, coil packs,fuel filter, spark plugs fuel injector cleaner, IAT change new O2 sensors etc. still the same problem. I don't think it is a fuel pump problem i hope the reflash will help fix the problem when i get a chance to do it.

hey can u explain about that system reflash and cold start thing what do u do and what happens and what do u need to do it thanks

If you go to the dealer they will look at you as if you are stupid tell you there is no reflash. If you go to this website put in your vin number it will come up with the relash part number which you can take to them to reflash your computer.

http://calid.gm.com/vci/VINEntryPre.do




2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time

oh ok did u change ur injectors just wondering

Haven't done that i was thinking about doing that. But i keep hearing that is not the problem but i still think it is that that though although no one can say for sure. The dealer has no idea. Then again the dealer did not even know there was a reflash for the computer.


2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time

geez this sux i cant drive my car i have no car i need to find out whats wrong with my car

What about changing the engine coolant temp sensor? Mine went bad and would run like crap when I first started it up. The computer uses that sensor and a couple other ones to determine how much fuel the car should be getting on start up. Maybe you are getting too much fuel for the spark plugs to ignite the mixture (or not enough). I'm not sure but good luck!


http://members.cardomain.com/scrawnyguy18

Do you have to pay for the reflash or does GM cover it?

You have to pay for it. The dealer told me it would cost about $70. to do the reflash.


2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time

I had put this in the other post but this seams to be the official post for it now.

When I go to this GM SITE and enter my vin number and look under PCM it shows my car as having these two updates to it that the dealership put on one of the times I took it in and I have the paper work that says these two were flashed on the PCM, part number 12216583 New calibration to address cold hesitation issue, part number 12208753 CALIBRATION TO CORRECT COLD HESITATION AND SLOW RPM DROP WHEN SHIFTING FROM FIRST TO SECOND GEAR. This fixed my cold hesitation problem but still ever 12,000 miles I have a misfire problem when I am sitting at a stop light the RPM's will jump up and down and you will hear it miss about every 45 sec. so I take it to the dealership and they will change the plugs, ignition coils, ignition housing, and the ignition module and it will be fixed for another 12,000 miles

The GM site is the one listed above http://calid.gm.com/vci/VINEntryPre.do

whoa! wait a sec. so that GM site you just linked has history of reflashes for every car that was flashed at the dealership? thats awesome i looked my 99z up and there were a few things listed -

12222103 12222102 N/A New calibration to address cold hesitation issue
9373243 9373172 N/A New calibration corrects concern related to knock sensor false light
9368543 9368542 N/A New calibration to correct hot restart problems
9365343 9365288 N/A CONTROL MODULE CALIBRATION

i havent taken the car to the dealership at all since i've bought it so does that mean that the previous owner must be responsible for all that? Also what do those part no.'s mean?

going in this saturday to get the reflash done at the dealer.


2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time

my cars engine was shakeing so much i broke my upper motor mount because of this problem

zlr ecotec wrote:ok i have the same problem but i have a 03 cav ecotec 45,000miles,i changed the spark plugs and added fuel injector cleaner and still does it. I'll try it, even though mine is not the same engine.

isnt urs still covered under warranty

ZFATALJ wrote:my cars engine was shakeing so much i broke my upper motor mount because of this problem

I had the same problem but with both mounts

Brett wrote:

ZFATALJ wrote:my cars engine was shakeing so much i broke my upper motor mount because of this problem

I had the same problem but with both mounts

so is ur car fixed or still broken and any suggestions what i should do

I have a similiar problem with my car, my idle will bounce around for a little while when the car is first started up. Also when I shift from first to second the RPM's drop and the car almost stalls out. However, when I put my VIN # in the site above it doesn't do anything. I put it in there like 20 minutes ago and it still says getting calibration information, but my little icon in the upper right of the screen has stopped like all of the info from the site has been received. How long is it suppose to take to get the info??

Mylife - Let us know how it works out for you




http://members.cardomain.com/scrawnyguy18

I was having the same issue with that site. Do you have pop up blockers or any blocking device you may need to disable it for a moment



2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time

Ok I finally got it to work, mine came up with
9351353 9351301 N/A Control Module Calibration
9353773 9353708 N/A Supersession to correct excessive false knock retard

So my question is.....what exactly does that mean? I still need to get it reflashed for the cold start and 1-2 shift problem right?


http://members.cardomain.com/scrawnyguy18

my car is doing the same thing



Proud owner of a 2002 Z24!

Got the reflash done today. Got it done for free. The lady was real nice. On the drive home the car seemed to idle smoother and run alot better. The true test will be when i wake up in the morning on go for a drive after it has been sitting for a couple hours. I will keep your guys up to date. If you have to pay for the reprogram it should run about $70-$80.


2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time