3.4 cutting out when on the gas

[913_4se]

my 91 3.4 cuts out when i get on the gas it does not matter what the temp is or out side or in the motor it seems like a TPS i replaced it the motor has done this since ive owned it all the timing is new and in time no codes either..... about half throtle it cuts out like i tured the gas if i let off the gas alittle it picks up fast its like the tps has a bad spot but doesnt i thought maybe the coils or computer ????

any thoughts ive about gotten used to it now but when i need to go sometimes i have to let off the gas to go sucks when a 2.0 honda pulls up by my side and it does it

[913_4se]

im going to try GM TEC and see if deposits are the cause of all this

[Slade901]

If you suspect the TPS is bad then make sure the TPS is secured in place with its two bolts. TPS can't be cleaned, you just have to replace it.

[lowes71]

I have a 92 lumina Z34 w/3.4 and it is doing the same thing.I replaced the tps,egr,iac,and the map sensors.And it still is doing it.If you give it little pedal pressure or full throttle it runs good but soon as you give it normal throttle it stumbles like crazy.I'm lost and don't know what to try now.

 

 

James

92 Lumina Z34 3.4

[913_4se]

i feel the same way ive put almost 2 or 3 of everything on it now ive put new tps,egr @$150,all upper gaskets,all temp switch's checked timing cams and all ,,,,,the only thing i know is that ive yet to replace the coil packs and the ECM and put new grounds on the motor ????

 

but ive read that carbon buildup can cause a lean out at some rpm's and at some temp's if i figure it out ill be sure to let ya know what fixes it

im open to anything

[95 3-4]

My 3.4 stumbles a little bit off idle, after that it runs fine it idles fine it cruises great, just a stumble for 2 seconds when pulling from a stop.............been driving it like that for a year, sometimes when acelerating the engine power will be fine then go down a bit then pull even stronger than at first and all three modes with nove moving of the pedal

 

Twice it has died on me in this year and it just wont start, it might try to make an idle it seems like it doesnt have gas and will jump around from 500-800 rpms then die, if you floor it it just backfires and dies off, sometimes it will do this while driving and when this happens i just hold it to the boards and it seems to clear up and get going, sometinmes a qucik neutral pop and try to rev it to the moon which aids the process, it dont do it often but the few times it has sucked, the 2 times it stalled it started and ran fine 15 minutes later

 

Junky problem and no codes or SES light, I was thinkging TPS, Cam, Or maybe ICM, I hate where my icm and coil packs are mounted, I wish mine were on top by the damn belt like i see on some w body cars

[913_4se]

have you checked the coverter i had a car once that did the same thing and cleaning it out by reving the motor was the only thing i could do for it untill someone told me to replace the cat it was a Beretta

 

when yours stops do you know if it is getting spark gas ect....

[913_4se]

well i fixed it and i could not be any more happy that its fixed

 

it was the ECM

 

i changed it out and wow what a differance it will smoke em now

the only thing i noice now is the shift point went from 5,500 to 6,700 red line now and the rev limiter was 4,500 to 3,500 now i guess this is right