engine or tranny?

[iaoun]

hi guys ,,,

two days ago i went out with my lumina SS 07 ( l98 6.0) ... quite similar to the g8 .... i parked and all was just fine ... i went back to the car after a long while ( 7 to 8 hours) ... (during that time there was a sand storm then some rain) ... anyhow ... i drove it for like 15 km then i started noticing that whenever i go slow ( 25 - 30 km/h) and i push the gas gently ,,, i feel the car is heave and the rpm is hardly moving... it will stay like that till it reaches (60 -70 km/h on the odo) then it comes back alive.... its not happening always yet i did that for few times in the last couple days ,,, last time it did that i tried to have full throttle at speed of 25 km/h and the result was that it shifts to a smaller gear and takes off as if it wakes up

i still cannot identify the problem ,... im really worried about that ,,, is it a transmission problem ? does the transmission have any sensor?( is it a sensor related problem ?)
or is it something wrong with the engine... oil pump lets say because i know that this problem occurs alot in the l98 ,,,
or does it have to do with the dust from the storm that day ?

[HSV-GTS-300]

Air cleaner full of desert?

[iaoun]

Originally Posted by HSV-GTS-300

Air cleaner full of desert?

CP ! ive cleaned the MAF yesterday using electronic QD cleaner ,,, its doing better now yet i think it needs more cleaning,, cause i didnt use much spray ,,

im gonna repeat the process over again and c how it turns out ... ill keep u posted

thanks dude !

[iaoun]

hey guys ,,, i cleaned the air maf ... yet still on second gear from speed 25 to 50 km/h the rpm moves slowww and after that it wakes up ! im not sure whats wrong ! :S

[BigKID]

Is it specific to second gear or will the engine lug in all gears in that specific rpm/throttle range?

[iaoun]

hi guys ,,, after a whole week at the workshop, and after a big bill ,,, nothing happened and the problem didn't go away,,,i don't even feel like driving the car anymore, im even having thoughts to sell it ...

they have changed the air filter, sparks , spark plugs, cleaned the injectors,MAF, the throttle and the throttle body ,,, when i went to receive the car the problem was always there ,the mechanic said that we need to change the MAF, and so i did , i bought a MAF and installed it myself, again same scenario, i can feel the car is chocking (not always , it happens only when i go half throttle or even quarter of the pedal.)

the question is ,,, installing a new maf needs any reset by connecting it to tech2 ?

is this related to any transmission sensor(if there's any), i think its not shifting to lower gear when its supposed to do so .. so its accelerating on 2nd or 3rd ...

im really pissed ,, i still dont know what to do !

please guys i need some professional help

[iaoun]

Originally Posted by BigKID

Is it specific to second gear or will the engine lug in all gears in that specific rpm/throttle range?

i cannot be specific, but wat im sure of is that its not shifting to lower gear when its supposed to,,, to be more clear,during a U turn i go slow, turn (speed arround 20/ 25 km/h) then go easy on the gas ... in this case the car is supposed to shift back to 1st ,,but its not happening ,,, what is happening is that it stays on 2nd or third ,,,i push the gas slowly and ascendingly once it reaches full throtte it goes back to first gear and take off fast ... as if i kick it but what im really doing is that pushing gently till it reach full thrtl! i duno if u got me ,,,, yet when i go for the same U turn and push the gas fast all goes normal ...

during that the rpm goes very slow till it reahes 70 /80 KM/h

i feel like its a sesnor related issue ,,, we changed what is supposed to be changed ,,,(sparks, plugs, filter, injectors cleanned , MAF was changed at home dunno if it needs any reset of the ecu ,,,, )

expecting your reply

regards

[BigKID]

So basically the trans is not downshifting with low throttle percentages as it once did...

Could possibly be the Throttle Position Sensor but not likely if your fueling is still good.
Other wise could be the the TCM or something wonkey in the tune. Have you done any tuning with any tuning software or handheld units? One thing you could try is resetting all the computers in the car by disconnecting the negative terminal from the battery and leaving it off for 15-20 min.

[iaoun]

Originally Posted by BigKID

So basically the trans is not downshifting with low throttle percentages as it once did...

Could possibly be the Throttle Position Sensor but not likely if your fueling is still good.
Other wise could be the the TCM or something wonkey in the tune. Have you done any tuning with any tuning software or handheld units? One thing you could try is resetting all the computers in the car by disconnecting the negative terminal from the battery and leaving it off for 15-20 min.

hi man ,,, thanks for your reply,,, TCM is what exactly?

i will try to rest my computer,,, i didnt do any kind of tunning,,,, i took it to GM maintenance service this morning and the guy who tested the car said that there was a shifting delay ... anyhow some others said it might be sensors or transmission programming...

whats the severity of the programming thing ? and
how much do the sensors cost!

regards

[BigKID]

Transmission Control Module.

If it still does it after reset, one way to check to see if it is tuning or mechanical is to have the car scanned to see if it is commanding gear but physically delayed in shifting or if the shift command is delayed and shifting when commanded.

[llcman]

i agree with big it should do the trick