99 Chev Mailibu Transmission Problems

Steve-Ont · 09-30-2007, 01:03 AM

Hi there .. hoping for a little advice.

99 Malibu
4 cylynder
200,000km

The car has had intermittment tranny problems for 2 months now. It began when hwy driving .. when I came back to the city ... the car would hard shift ... and hesitate off the line.

It has now progressed to almost everyday .. with a new added twist to the mix ... start up .. head out on the road with no problems ... get on the highway ... and I seem to lose my throttle on the onramp. Pedal down ... rpm's seem to drop ... car will only slowly speed up. It happens intermittently as well .... sometimes there ... sometimes not. I can drop the car into neutral at any given point and rev it up ... so it leads me to believe that it is electrical. Switch ... sensor.

It did flash a check engine for the first time the other day as well .. which has resolved. Can the codes be had through the ignition on off ...similar to an intrepid?

Any advice would be greatly appreciated.

Thanks very much for your time.

Steve

**qldit** · 09-30-2007, 02:17 AM

Good Evening Steve-Ont, have you checked to see if the fluid level is correct?
Put it through all the gears for a few seconds with the brake on, then shut down and check the fluid level.

Smell the fluid for any burning odour, should be clear and red.

Others will have different ideas.

Cheers, qldit.

Steve-Ont · 09-30-2007, 08:36 PM

Thanks for the quick reply .... I should check the fluid ... Gm was nice enough to not include a dipstick .. has to be checked similar to a differential I would imagine ... side plug ... and I have no ramps. :( Next time it's in the shop ... I'll be sure to have it checked.

Lucked out today when filling my propane .. it happened to be the owner of the autoshop pumping on a Sunday. Started chatting with him about codes .. he offered to scan mine free of charge. :)

Came back with a code pointing to the throttle position sensor ... that was the only code stored in memory.

Now I just have to price it and find it. lol

If anyone else would like to chime in about any other possible problems with what I've described that would be great.

**qldit** · 09-30-2007, 09:15 PM

Good Afternoon Steve-Ont, that is interesting, I am not familiar with that vehicle, but often stored codes do not neccessarily mean that sensed component is bad, it may only be a momentary glitch to produce a code.

The throttle postion sensor may involve the "kick-down" system for the transmission but the symptom mentioned may also happen with low fluid level, apart from numerous other possibilities.

In that you have no steady light it sounds strange.

Maybe disconnecting the battery for a short period may have some effect.

Your radio code may need reinstalling if you try that.

Aren't hi-tech machines a lot of fun!!

Cheers, qldit.

Steve-Ont · 09-30-2007, 10:28 PM

lol ... loads of fun. The mechanic also mentioned something similar .. he reset the code for me ... to make it appear the repair was made. He mentioned finicky codes / electronics and wondered if resetting it would help matters.

I have a friend who has a 2002 Grand Prix .... he has had a similar situation with his ... when travelling on the hwy for 30kms or more ... it will hard shift slightly as he hits the city streets.

I will try to squeeze under the car this coming week and check the level .. smell the fluid .. to eliminate that as the culprit.

One other thing I forgot to mention as well .... when the car seems to lose it's throttle .. I can shift down to 1, 2nd, 3rd .... and the power is always there. I can't pinpoint it to overdrive either .. as it has happened at very speeds, rate of acceleration.

The TPS .... when I lost throttle on the hwy .... I shifted it to neutral ... revved it up as it should. So it seems to know the position of the sensor.

I'm lost as well .... that code was the only code showing as we looked at the scanner today.

Thanks again.

Steve-Ont · 09-30-2007, 10:30 PM

Ahhh .. the other thing about the code .... it was slamming fairly hard one day ... the code appeared ..... worked 10 hrs ... the code still remained.

When I started the car the following evening to head to work ... the code had cleared.

Thanks.

**qldit** · 09-30-2007, 10:55 PM

Good Afternoon Steve-Ont, Oh, that is getting to relatively damning for that throttle position sensor!

I haven't stripped on of these later series transmissions down, they have a lot of electronics involved that is partially shared with the main computer.

I have no idea how to troubleshoot them.

Maybe the Haynes service manual for that model could prove useful.

From your clues you should be able to pipoint possibilities.

That is ridiculous having no dipstick to check transmission fluid level!

Best of luck old chap!

Cheers, qldit.

Steve-Ont · 09-30-2007, 11:10 PM

I am planning on picking up the Chilton Repair Manual from the library this week. I was hoping someone might have access to the TSB's for this model.

I have requested them from the dealer in town once before .. and they begrudgingly gave them to me. Should I test my luck was again. lol

Thanks again for taking the time to ponder my lovely Malibu. lol

Steve

**Midnight Tech** · 09-30-2007, 11:21 PM

Steve, go to www.1800autotalk.com and there's a button at the bottom to enter your VIN and it should give you any TSBs or recalls.

Steve-Ont · 09-30-2007, 11:30 PM

Hey Midnight Tech .. thanks for the response.

I should have worded that differently .... the TSB that is put out to the dealer's.

I mentioned a problem with our Montana ... he went directly to that subsection ... where all known customer complaints are listed with cause and effect .... plus the subsequent repair procedure.

It gave a tree like effect for the repair .... this symptom head in this direction.... etc.

Thanks again.

09-30-2007, 01:03 AM	#1 (permalink)
Steve-Ont Registered User Join Date: Sep 2007 Posts: 6 OS: Win 2000	99 Chev Mailibu Transmission Problems Hi there .. hoping for a little advice. 99 Malibu 4 cylynder 200,000km The car has had intermittment tranny problems for 2 months now. It began when hwy driving .. when I came back to the city ... the car would hard shift ... and hesitate off the line. It has now progressed to almost everyday .. with a new added twist to the mix ... start up .. head out on the road with no problems ... get on the highway ... and I seem to lose my throttle on the onramp. Pedal down ... rpm's seem to drop ... car will only slowly speed up. It happens intermittently as well .... sometimes there ... sometimes not. I can drop the car into neutral at any given point and rev it up ... so it leads me to believe that it is electrical. Switch ... sensor. It did flash a check engine for the first time the other day as well .. which has resolved. Can the codes be had through the ignition on off ...similar to an intrepid? Any advice would be greatly appreciated. Thanks very much for your time. Steve

09-30-2007, 02:17 AM	#2 (permalink)
qldit TSF Gearhead Join Date: Mar 2007 Location: Brisbane Australia. Posts: 592 OS: All Systems, mainly Linux	Re: 99 Chev Mailibu Transmission Problems Good Evening Steve-Ont, have you checked to see if the fluid level is correct? Put it through all the gears for a few seconds with the brake on, then shut down and check the fluid level. Smell the fluid for any burning odour, should be clear and red. Others will have different ideas. Cheers, qldit.

09-30-2007, 08:36 PM	#3 (permalink)
Steve-Ont Registered User Join Date: Sep 2007 Posts: 6 OS: Win 2000	Re: 99 Chev Mailibu Transmission Problems Thanks for the quick reply .... I should check the fluid ... Gm was nice enough to not include a dipstick .. has to be checked similar to a differential I would imagine ... side plug ... and I have no ramps. :( Next time it's in the shop ... I'll be sure to have it checked. Lucked out today when filling my propane .. it happened to be the owner of the autoshop pumping on a Sunday. Started chatting with him about codes .. he offered to scan mine free of charge. :) Came back with a code pointing to the throttle position sensor ... that was the only code stored in memory. Now I just have to price it and find it. lol If anyone else would like to chime in about any other possible problems with what I've described that would be great.

09-30-2007, 09:15 PM	#4 (permalink)
qldit TSF Gearhead Join Date: Mar 2007 Location: Brisbane Australia. Posts: 592 OS: All Systems, mainly Linux	Re: 99 Chev Mailibu Transmission Problems Good Afternoon Steve-Ont, that is interesting, I am not familiar with that vehicle, but often stored codes do not neccessarily mean that sensed component is bad, it may only be a momentary glitch to produce a code. The throttle postion sensor may involve the "kick-down" system for the transmission but the symptom mentioned may also happen with low fluid level, apart from numerous other possibilities. In that you have no steady light it sounds strange. Maybe disconnecting the battery for a short period may have some effect. Your radio code may need reinstalling if you try that. Aren't hi-tech machines a lot of fun!! Cheers, qldit.

09-30-2007, 10:28 PM	#5 (permalink)
Steve-Ont Registered User Join Date: Sep 2007 Posts: 6 OS: Win 2000	Re: 99 Chev Mailibu Transmission Problems lol ... loads of fun. The mechanic also mentioned something similar .. he reset the code for me ... to make it appear the repair was made. He mentioned finicky codes / electronics and wondered if resetting it would help matters. I have a friend who has a 2002 Grand Prix .... he has had a similar situation with his ... when travelling on the hwy for 30kms or more ... it will hard shift slightly as he hits the city streets. I will try to squeeze under the car this coming week and check the level .. smell the fluid .. to eliminate that as the culprit. One other thing I forgot to mention as well .... when the car seems to lose it's throttle .. I can shift down to 1, 2nd, 3rd .... and the power is always there. I can't pinpoint it to overdrive either .. as it has happened at very speeds, rate of acceleration. The TPS .... when I lost throttle on the hwy .... I shifted it to neutral ... revved it up as it should. So it seems to know the position of the sensor. I'm lost as well .... that code was the only code showing as we looked at the scanner today. Thanks again.

09-30-2007, 10:30 PM	#6 (permalink)
Steve-Ont Registered User Join Date: Sep 2007 Posts: 6 OS: Win 2000	Re: 99 Chev Mailibu Transmission Problems Ahhh .. the other thing about the code .... it was slamming fairly hard one day ... the code appeared ..... worked 10 hrs ... the code still remained. When I started the car the following evening to head to work ... the code had cleared. Thanks.

09-30-2007, 10:55 PM	#7 (permalink)
qldit TSF Gearhead Join Date: Mar 2007 Location: Brisbane Australia. Posts: 592 OS: All Systems, mainly Linux	Re: 99 Chev Mailibu Transmission Problems Good Afternoon Steve-Ont, Oh, that is getting to relatively damning for that throttle position sensor! I haven't stripped on of these later series transmissions down, they have a lot of electronics involved that is partially shared with the main computer. I have no idea how to troubleshoot them. Maybe the Haynes service manual for that model could prove useful. From your clues you should be able to pipoint possibilities. That is ridiculous having no dipstick to check transmission fluid level! Best of luck old chap! Cheers, qldit.

09-30-2007, 11:10 PM	#8 (permalink)
Steve-Ont Registered User Join Date: Sep 2007 Posts: 6 OS: Win 2000	Re: 99 Chev Mailibu Transmission Problems I am planning on picking up the Chilton Repair Manual from the library this week. I was hoping someone might have access to the TSB's for this model. I have requested them from the dealer in town once before .. and they begrudgingly gave them to me. Should I test my luck was again. lol Thanks again for taking the time to ponder my lovely Malibu. lol Steve

09-30-2007, 11:21 PM	#9 (permalink)
Midnight Tech Admin/Head GreaseMonkey/Igor's alter ego/Grand Exalted PoohBah Join Date: Dec 2001 Location: SC Posts: 2,920 OS: Windows XP Home/Pro SP3/Windows 98SE/Fedora Core 6/RH 7.2 with Autopoint/TAMS II	Re: 99 Chev Mailibu Transmission Problems Steve, go to www.1800autotalk.com and there's a button at the bottom to enter your VIN and it should give you any TSBs or recalls. __________________ Please post all questions in the appropriate forum. Questions sent by email or PM will not be answered. Sharing my life...with my Imzadi! Interested in Trek gaming? Check out the Dynaverse! Proud supporter of the Carolinas Aviation Museum. If we have helped you in any way, please donate to keep TSF up and running!

09-30-2007, 11:30 PM	#10 (permalink)
Steve-Ont Registered User Join Date: Sep 2007 Posts: 6 OS: Win 2000	Re: 99 Chev Mailibu Transmission Problems Hey Midnight Tech .. thanks for the response. I should have worded that differently .... the TSB that is put out to the dealer's. I mentioned a problem with our Montana ... he went directly to that subsection ... where all known customer complaints are listed with cause and effect .... plus the subsequent repair procedure. It gave a tree like effect for the repair .... this symptom head in this direction.... etc. Thanks again.