Random misfire/bogging

[Bigsyke]

I think the EGR temp sensor (between intake runners 2-3) is 100k ohm and the EGR resistor is 1m ohm.

if you have removed the EGR system then you DO need to put the resistor for the EGR temp sensor in.

The resistors helped me out alot, it was a night and day difference. Also the hickups you speak of may be the idle screw. I need to put locktite on mine. An intake leak pay throw a MAF code.

Both sensors will affect engine opperation I believe, thus the resistors.

[rex2sx]

EGR wont cut out you motor like that though. Well it shouldnt. Itd have a rolling idle and a normal-type operation at cruise.

Maybe the CKP sensor is going bad, or your ignition control module. Whats been replaced/checked since then besides the MAF and IAT?

[Bigsyke]

Originally Posted by rex2sx

EGR wont cut out you motor like that though. Well it shouldnt. Itd have a rolling idle and a normal-type operation at cruise.

Maybe the CKP sensor is going bad, or your ignition control module. Whats been replaced/checked since then besides the MAF and IAT?

Yes, it could;

Egr exhaust tube being cracked/leaking is a leak before the o2, which could make you run rich.

EGR gasket leaking could cause a vac leak, which throws the MAF readings.

IAT can be discarded.

Any vac leak could cause a stumble like that vs a honda where the MAP sensor usually causes a roaming/high idle. A vac leak could mess with the fuel reg

[LA_phantom_240]

Originally Posted by Bigsyke

Yes, it could;

Egr exhaust tube being cracked/leaking is a leak before the o2, which could make you run rich.

EGR gasket leaking could cause a vac leak, which throws the MAF readings.

IAT can be discarded.

Any vac leak could cause a stumble like that vs a honda where the MAP sensor usually causes a roaming/high idle. A vac leak could mess with the fuel reg

EGR port on the header is welded shut, no leaks there.
EGR gasket isn't likely, because it was replaced when I took the EGR valve off and blocked the cast iron piece it mounts to on the manifold, and I pull a good vacuum.
Hasn't thrown any MAF codes in a while (that I know of).

Originally Posted by rex2sx

EGR wont cut out you motor like that though. Well it shouldnt. Itd have a rolling idle and a normal-type operation at cruise.

Maybe the CKP sensor is going bad, or your ignition control module. Whats been replaced/checked since then besides the MAF and IAT?

What's a CKP sensor?

Only things changed since then and now are... um... oil and filter. That's about it.

[rex2sx]

Originally Posted by Bigsyke

Yes, it could;

Egr exhaust tube being cracked/leaking is a leak before the o2, which could make you run rich.

EGR gasket leaking could cause a vac leak, which throws the MAF readings.

IAT can be discarded.

Any vac leak could cause a stumble like that vs a honda where the MAP sensor usually causes a roaming/high idle. A vac leak could mess with the fuel reg

Eh, i dont know how much it can throw off your MAF reading if the valve is on the manifold. I wouldnt discard the IAT or else it wouldnt be there in the 1st place. Hes hitting a major fuel cut problem its not like its a buck or hesitation. So it would be a large leak to make the car bog down that bad.

CKP is crank sensor. Check the knock sensor at the PCM, you dont have to go under the hood.

[BigVinnie]

Bogging issues between idle and 3000RPM are the knock sensor.
Bogging issues from idle to redline are going to be egr temp sensor and upstream O2 sensor.
Bogging can also occur if the TPS isn't in the correct position.

If you have removed egr equipment and are throwing an egr code its more than likely from the egr temp sensor.

[YUNG DRIF]

He y I might can help
I had the same exact problem
bogging low idle, cuts off for a quick second. here try this

my problem fucking MAF was clogged like shit so clean maf really good runs greart
fuel pump can be going out
fuel filter
check your plugs
to much oil(lol) it can be happened to my bro 3 years back
check all your grounds
last but not least tps

[BigVinnie]

Originally Posted by LA_phantom_240

Which sensor is the EGR temp sensor? I don't recall ever seeing one... and I tried searching a while back for what resistance value to use for the knock sensor, but everything I came up with was detrimental to the car's driveability.

Here is the location of the EGR temp sensor and a socket I fabbed up to replace egr temp sensors without removing the entire intake manifold.

[LA_phantom_240]

Originally Posted by YUNG DRIF

my problem fucking MAF was clogged like shit so clean maf really good runs greart
fuel pump can be going out
fuel filter
check your plugs
to much oil(lol) it can be happened to my bro 3 years back
check all your grounds
last but not least tps

MAF cleaned 10k miles ago.
Fuel pump 6k miles ago.
Fuel Filter (Z32) 12k ago.
Plugs 12k ago.
Oil is fine.
Grounds (afaik) fine.
TPS, don't feel like fucking with. It's just a KA.

I was wondering WTF that sensor was. I knew we didn't have a MAP sensor... So what do I do? Put a resistor on that sensor's harness? Thanks a bunch Vin. You're the man.

[YUNG DRIF]

Let me add...

The screen on the maf right were your air filter would be
grab a clean towel and wipe it good see how much dirt comes off
thats screen
this screen gets clogged when in reality it seems clean
do this asap

[YUNG DRIF]

This problem has something to do with your MAF or your intake

[LA_phantom_240]

Originally Posted by LA_phantom_240

MAF cleaned 10k miles ago.

MAF is fine.

[rex2sx]

Yeah..If you have no egr then this probably is not the problem.

Maybe you should try swapping in a known good MAF

Its either your spark or fuel thats giving you problems..so..

Ign module?..i dont evn kno where it is on KAs

[LA_phantom_240]

Originally Posted by rex2sx

Yeah..If you have no egr then this probably is not the problem.

Maybe you should try swapping in a known good MAF

Its either your spark or fuel thats giving you problems..so..

Ign module?..i dont evn kno where it is on KAs

I swapped the MAF from my S14 parts car, and it seemed to fix the problem... then it randomly cut out again.

I'm pretty sure it's spark related, because a friend's Honda did something similar and it got worse til his distributor crapped out. Also, sometimes I'll be idling in a parking lot or something, and the car will cut out, and the the engine RPM will drop to like 400 and come back up to its normal speed all within like half a second... like I shut the car off and turned the key back on before the engine stopped.

It's gotta be ignition related. I'm gonna grab the dizzy off my other S14 and see what happens.

[LA_phantom_240]

The misfire seems to be heat related. A few days ago, it was incredibly hot outside, my car had been in the sun all day without being run, until I left work at 5:00. Hit the interstate, and the car runs fantastic. I get off the interstate, and all hell breaks loose. It began cutting out on me for like 5 seconds at a time. Really pissing me off.

What would this suggest is going out?

[rex2sx]

Ign modules fail when they get hot. But they usually shut the car down

Electrical components and heat dont go together. The only way i know that you can test it is with an oscilloscope, but other than that i am not sure

Did you get that other S14 dizzy?

[LA_phantom_240]

Originally Posted by rex2sx

Ign modules fail when they get hot. But they usually shut the car down

Electrical components and heat dont go together. The only way i know that you can test it is with an oscilloscope, but other than that i am not sure

Did you get that other S14 dizzy?

Haven't had time. I'll do it tomorrow most likely.

The car literally shuts down when this happens. It doesn't backfire through the exhaust like it's throwing raw fuel and igniting in the exhaust or anything. My exhaust is super smelly from ghetto EGR deletes and such, and I don't smell it at all when this happens... like the ECU loses signal and I lose spark and fuel.

[rex2sx]

That does sound like the ignition module so i guess youll know when you swap dizzys.

GL

[c-los13]

i been having almost the same problems
my car has been bogging like crazy lately but then i remembered when i put the colder intake i forgot to tie the wires that go to the MAF and one of the grounds got cut, i managed to kinda fixed it but the car would run horribly....i would seriously feel like crying cuz i have alot of pride in my car....next day i got the part that got cut rewired and the car started running better but that bogging and running rich as heck came back last week!!! ima get the all the wires that go to the MAF redone next week
dude check the wires that go to the MAF, the MAF might be clean but the wires are proly too old....
ps mine is a 91 hatch

[Deviousjet]

I think everyone has had this problem. I hope that you figure something out because this is annoying.