when I step my gas pedal and floor it, my car starts to bog. It only happens when I floor it though. Whacha think it might be?

if I remember correctly, my GF had the smae problem with her 4g63 where acceleration bogged and the idle fluctuated.
Check the resistance of your plug wires (the ohms from wire 1=>4 should be decreasing). Then glance down to make sure both 02 sensor are intact.

the way I fixed her problem was disconnect the negative terminal for an hour then started back up. Note that the car will run sluggish for the first 5+ miles. the PCM will need time to relearn the air/fuel curve.

good luck. hope this works out for ya.

kaiser

CW! j/k

96RS ~ full 99GS special body conversion, aem cai, greddy header, greddy sp exhaust, afx pulley, b&m sS, magecores & NGKs, S-AFC, Sparco Torino, illuminas, prokits, ingalls camber, gunmetal GS rims, ST Sways, STBs, lower rear tie bar, sound system, a shit load more.

97GSX ~ K&N FIPK, Greddy IC Piping, Type S bov. To all the haters _|_ tia

eclipskaiser:

I tried what you suggested but did not work. I hoked up the dataloger and it shows that both my 02 sensors are not working(WTF?)
I also noticed that when it bogs, my A/F gauge shows that is running lean. what the hel could be wrong?

your a/f gauge hooks to your O2 sensor. if neither sensors are working your a/f gauge is useless

I've seen this happen with a clogged cat. When its the cat its usually accompanied by a bad smell, and in extreme cases the cat will get REAL hot and even start to glow.

oh yeah, and it usually destroys the o2 sensor.

Seems like bogging is associated with richness. How is your idle? here are my thoughts:

1st theory:
yeah that is weird how the datalogger would indicate that both 02 sensor would go bad. Much like other's said, if your senosrs are bad, then chances are your car would not be running lean, as there is no way for the computer to measure air/fuel. it should infact go rich by default to protect the engine (in theory).

what are some of your resistance readings across the plug wires?

2nd theory: could be that your MAS went bad? not sure how you would check this though. Might have to consult with the DSM list.

3rd theory:
If electrical isn't the problem how about mechanical?When ws the last time you changed your fuel filter, plugs, plug wires, or pump? also can it be that you filled up on some dirty fuel?

Like I said before, with my girl's car, after letting the CEL clear out, we drove it around. Intial symptom was the idle was really shitty. i constantly had to rev it to keep it alive as idle was 100rpm. accleration bogged from 100rpm till 2000rpm where boost hit. Beyond that point, the car ran fine. after Boosting it for a about 3 miles, the car is running fine since.

I hope someone with more knowledge of the 4g63 would step up and contribute. Worse comes to worse, on saturday bring your car to RRE and have Mike W. Professionally check it out for ya. Not too far from speedzone.

let me know what else the datalogger indicates. Oh by the way for comparison, her mods are:

Greddy Type-S BOV
Injen Intake vented back into intake tract (gotta keep the MAS happy)
RRE upper IC
Apexi N-1 3" catback
RRE high flow 3" cat
Blitz TT (indicating 1.10 bar)
VDO gauge (indicate 15.9 lbs)

good luck. let me know if I can help out in any other way.

kaiser

Bro I was just having this same problem the other day. Got on the gas and the car would lean out and would be slugish and jerk. I replaced my plug wires with some nice MSD 8.5 mm wires and replaced my plugs, runs perfect now. Check there, I was freakin out about my ride but it turned out to be a simple fix.

Yeah, could be a bad plug wire. (my answer for everything) :)
Clogged cat would smell like sulfer (eggs). And to reset the CEL, you only have to disconnect the terminal for a min or so. 5 min. will definetly do it.
But seriously, pull your plugs and see what kind of shape they're in. Your definetly running rich. See if it's all 4 cyls. or just one. If it's just one, than it's a wire. If it's all, then, best of luck to ya!

-Tony 98'GST



http://eclipzgst.dyndns.org
AIM: YNOT420247

well I took it to my friend's shop and hooked up the dataloger back because the CEL came back on and we erased it again. The 02 sensors showed being bad with a reading of .02 and after a long as day we found out that my MAS was bad *cries* reading 3. I called satan and asked for the price for it and it came out to be $456.88 total and I just said f@ck that.Another friend seemed to had one laying around in his house and let me try his and WALAH!! it read .10. No more lean running and the dataloger started reading the 02 sensors at .07
..now the problem that it has is that it bogs a little but doest run lean anymore..I will find out tomorrow if it will get out of the shop just fine..

glad you solved part of your problem. the readings sounds normal.

Just not too sure about the slight bog though. Good thing your friend hooked you up as MAS' are expensive from the dealership. Norco Mitsu do give 20% discount on parts.

Does someone have the old DSM card? if so, does the 20% off carry into labor?

kaiser

(keep in mind it's 7am...) um, wut's a "MAS" ?

>(keep in mind it's 7am...) um, wut's a "MAS" ?

Mass Air Flow Sensor but I dont think you have one of those bro

o. my bad :)

YIPEEE KAIYAYYYYYYY!!!!
my car is fixed...new MAS and spark plugs and..WALAH!!!! than everybody for the goos help..I really appreciate it thanx