hi guys k, its been a bit over a week that at about 5-5500 rpm my car feels like it dies on power (maybe even closer to 6k, but anyway), mainly in 1st and 2nd gear. itll run strong all the way till there, and then it falls off of power so much i gotta chnage gears. at highway speeds in 3rd and 4th it pulls like crazy all the way to 6700 rpm. im gonna do some searches as well to get soem ideas, but any input would be welcome.

any thoughts on what to check first? wires? plugs? maybe its the fuel pump? o2 sensors? im gonna give it a quick lookover on monday to see if i can visually spot anything out of place. thanks guys

 

you could be running out of fuel are you still using stock injectors/regulator?

 

Although this probably isn't going to help much, but I had a hesitation at about the same RPM but in all 3 gears during a run (Automatic though)... Nothing I did seem to help, replaced lots of things... but then, almost by accident when messing around with my PCM tune, I added some advance to that RPM range, and it went away.

Probably not going to help much, but thought I would throw it in the mix...

Good Luck!

 

i had the same problem i took it to the shop and they swear its the opti. ill find out when i replace it i guess. i belive someone else on here had a simular problem and it turned out to be the iac.

 

using 30# svo's. tuned for them as well. regulator is stock.

i just changed the coil and coil wire, and took it for a quick spin, and its still the same. lotsa backfiring, and feels like its running on 6-7 cylinders. depends though, from time to time itll rrun strong, then its weak.

car hasnt had the ses light come on, but is it possible theres "silent" codes?? such as, itll throw a code without showing the light? if so, i guess i could get it scanned and see what comes up.

it was a BEAST up top, till this now, i dont go much above 5k rpm cause the cars barely pulling.

is it possible an old/f**ked up o2 sensor could be the cause of this? the o2 on the passenger side is new, but the drivers side is as old as i can remember. possibility? or not? i have had an o2 go bad before, but the symptoms were completely different than this. so....

fuel pump? ignition module? opti? whats anyones guess or opinion on this?

thank you very much as always everyone

 

i am thinking opti now

 

I had the EXACT same problem....except the miss occured more in 3rd and 4th compared to 1st and 2nd. So, I started off with replacing the wires....noting, next I replaced the coil....nothing, then I tried the plugs (only one bank at a time. I did the driver side first)... nothing, then I did the passenger side bank and whammo my miss was gone. My number 4 plug was toasted.

so maybe you should try your plugs. My plugs only had 21000 kms on them and they were ****ed so maybe its the same for you.

 

i think coil

 

i was thinking of going with the plugs next as well i put new ones in this winter, and they have about 35000 kms on them now. ill do them in the next few days. i gotta hunch that it might be that as well. thanks

for the person who said coil, i chnged it. didnt go away....

for some reason, i wouldnt count the opti out just yet. i do have a spare one, but thatll be a last resort.

thing is, anywhere above 3k rpm, when i let off the gas, the backfire occurs at the same time, everytime. for example, i give it some go, let off the gas, count 1,2, then POW backfire. doesnt fail.

ill post back if its fixed and how for future refernce thanks guys