assimilated420

ok this is just seeming to come about for NO reason..

my car was running a bit richer so i had changed the o2 sensor finally yesterday and now... it seems to be running fine but as i take it out and it drives like it was before no change.. and then as i am goin around and comin home.. it just starts hitting a brick wall.. and when im in neutral.. it revs up to red just fine.. but as i am driving when it hits 2000 it just starts sputtering and bogging down but if i pump the pedal.. it jumps up and revs up like normal but it does this between 2000-3000 rpm.. very odd.. it sounds like its trying to breathe but almost as if its being choked of air and too much fuel as i can see the smoke comin out the back.. it does it both while warm and cold.. and only when im driving.. if im in neutral/park it doesnt happen

jfairladyz

It could be your detonation sensor retarding the timing and limiting your revs as the ignition is controlled by the ECM in turbo cars. Alot of the time, a car won't experience detonation until it's placed under a load like driving it.

jfairladyz

Another thing to check is the inhibitor switch circuit from the automatic transmission. Those are the only two things I can think of that would be load specific. There are lots of things that can limit the engines ability to rev, but to only do it under load is, as you said, odd.

ThermalWake

u know i got a 79 zx 2+2 5spd. its not an auto but the other day i made a 200 mile drive to pick up my new kat.. literally a kitty kat. and uhh my car was havin the same typa problem. i returned to my dads house, and it might or might not be the same problem but my car was boggin between 1500 and 3500 rpms. i came to realize that there was a popping sound coming from the coil. the +/- line were arching onto the main distrubitor line, causing it to bogg around the same rpms you are.. its just an idea.. thats wat fixed mine.. check to see if the 2 both positive and negative line on the coil are too close to the main wire going to the distrubutor. if they are just space them away from it as far as u can.. if that doesent work.. then i dunno wat to tell u im new at these Z's.. but theyre soo fun!!

assimilated420

that sounds like whats goin on with mine but only under load.. im doing a total scan of evry part i can possibly do on my car and find the problem.. this is just a lil weird..

assimilated420

wow ok.. some interesting results today but still nowhere...

i took it out this morning as i wanted to have a fresh idea of whats the problem and i listened and evrything and this is what i concluded after thinking about it all last night.. it sounds as if its not getting spark somewhere.. or something sporadic.. i checked all my spark plugs and they were fine.. the wires are new.. but the cap.. that was weird cuz the the middle springy contact that touches the rotor was like either ground down or just embedded in the casing in the plastic and the plastic was all scratched and the contact was worn away flat instead of rounded.. and the rotor had signs of wear.. i also checked the coil and the contacts to make sure no arcing was taking place and made sure all wires were tight and snug.... well i pieced it together.. and low and behold it ran fine again!!! didnt do a damn thing but like take it apart and piece it back and it was doin this cold or hot... so this isnt some thing that happens only when its up to temp.. mso i drove it around and it was flying! so im like.. what the hell.. well i take it back and i ordered the cap at OReilly and i go back later to pick it up.. and the way there it was going great till like 100 ft from the store and it starts doing it again... so im like what the f*$%!!! i replaced the cap and pieced it together and as stated previously it runs and idles great when in neutral or park.. but when i start driving it starts bogging down.. and to me it souns like its just not firing on all cylinders when i accelerate.. like its blowing smoke out the back and it smells of fuel so im not firing every cylinder when i accelerate but when i maintain a constant speed it runs smooth.. but this only occurs at ~2000-3500 rpm..

when i am going i can hear the relief valve releasing pressure and when it starts to bog and stumble i hear the fluctuations in the air.. as this goes on.. i can hear it trying to get past whatever and if i release and stomp the gas a couple times the rpms just jump up and when i hit past 3500 it just goes VROOOOoom and thats not always good cuz kingwood is crawling with pigs and if i dont release the gas it just accelerates like a beast who just broke free.. but when i release it just starts bogging again..

my conclusion is something with the ignition system.. and i havent a clue what it is and i have depleted my funds.. arghh why must **** happen like this.. this is not something thats ever happened before and its like my car just keeps hittng a brick wall evrytime i repair something..

RodMoyes

I'm not sure if I read your post correctly, but it sounds like you were describing the ignitoin rotor and or the inside of the cap being mangled. If that's the case... You have a problem with the distributor rocking. Have you checked out the dizzy lately?


Rod.

assimilated420

nonono it wasnt mangled.. the middle contact was worn down where it touches the rotor is all but i have replaced the cap and the problem still exists...and it doesnt have any wobble or play...

assimilated420

this problem is beginning to tick me off... this **** just happens out of nowhere and i know its something with my ignition.. what would cause the igniton to retard or act up at 2-3500 rpms only while driving.. my relay and sensor are fine.. i thought the cap was what posed the problem but thats replaced and this problem stopped after i removed and replaced the plugs, wires and tightened down the contacts for the coil.. and i see no signs of arcing anywhere..

jfairladyz

The knock sensor will cause your ignition to retard to control detonation. You're motor doesn't have to be detonating though, the sensor could be bad. Also, the ecu in the turbos controls timing, so you might want to look into that. It's also just possible that you got a loose connection somewhere in the ignition thats working itself loose while you drive. Might want to check out the IM too. You might be getting enough spark while you're idling, but not enough to power the engine while its under load. Make sure all the resistances are right in the ignition system.

assimilated420

i found the problem.. but this only causes new problems.. financially of course..

i isolated it to the IM and the coil.. well i noticed when i had removed the wires on the coil and replaced them that thats when the problem would dissapear mysteriously for a short while.. i think my coil is prolly on its last leg.. so now im in a spot of needing a new/used coil for however much..
this problem has just boggled my mind cuz i usually when the coil goes out you cant accelerate anywhere past a certain point but this is just been up and down.. like i said, very odd...