Stumble problem, possibly running rich?

[zachattack_5491]

So my S13 just started stumbling, all speeds, all temperatures. I checked out the FSM, and it said to first check the o2 sensor then check the EGR.

Did the o2 diagnostic, and it said I was running rich for about 20 seconds and lean for about 3. Got a new sensor and it says the exact same thing.

I removed all the emissions crap thinking it would help, I even thought it could possibly make it worse. But I started it up today and it's no better or worse.

The codes I'm getting are 34-knock sensor and 14-speed sensor. Which have been there since I got the car. So does anyone have any ideas on what to do?

[Klits562]

MY car stumbled quiet a bit when i first got it. If you removed the emissions equipment make sure you plugged up ALL open lines.Check your timing and all vacuum lines to make sure you dont have a vacuum leak, did this with my car and it cleared it riiiight up.

[zachattack_5491]

Yeah, everything's plugged up 100%. I only have one vacuum line to the fpr. I was thinking timing too, but wtf? How does my timing just all the sudden get messed up? I'm gonna be pissed if I go buy a timing light and it's not the timing I'm on a college budget. Eating Ramen noodles, but dropping 100s of dollars in my car haha. That's how I roll.

[Klits562]

i know how you feel i make only 220 bucks every two weeks and im literally broke the day i cash my check.anyway idk what would cause your timing to change on its own.You dont have to buy a timing light just unbolt your dizzy and turn it a bit in both directions to see if it makes your car run better, if it does then maybe you should go buy a timing light and get it accurate.Also how many rpms are you idleing at when the cars warmed up.

[Klits562]

Also if your catalytic converter is clogged it can make your car run like sheeet
Modified by Klits562 at 1:36 AM 9/22/2009

[zachattack_5491]

i know how you feel i make only 220 bucks every two weeks and im literally broke the day i cash my check.anyway idk what would cause your timing to change on its own.You dont have to buy a timing light just unbolt your dizzy and turn it a bit in both directions to see if it makes your car run better, if it does then maybe you should go buy a timing light and get it accurate.Also how many rpms are you idleing at when the cars warmed up.

Haha, strait up. Well I dunno, I'd prefer not to completely destroy anything... I just turning the dizzy sounds like a recipe for disaster lol.

Also if your catalytic converter is clogged it can make your car run like sheeet

My cat is hollow

[240sxKAT89]

Mine did the same thing yours is doing, and it may sound stupid but i pulled off the hose that connects the intake and Idle Air Control Valve.Now it runs smooth, at idle as well as when im driving.

[moso]

if your getting a knock sensor code then its possible that the computer is putting the car in "limp in" mode to try and keep it from knocking. if the sensor is bad which is likely it needs replaced and "should" clear up your problem. im not sure why it hasent done this before now. hope this helps.

[zachattack_5491]

Mine did the same thing yours is doing, and it may sound stupid but i pulled off the hose that connects the intake and Idle Air Control Valve.Now it runs smooth, at idle as well as when im driving.

Yeah, I've had some IACV problems in the past. So I guess I'll test that theory out.

if your getting a knock sensor code then its possible that the computer is putting the car in "limp in" mode to try and keep it from knocking. if the sensor is bad which is likely it needs replaced and "should" clear up your problem. im not sure why it hasent done this before now. hope this helps.

I'll order a new sensor today. That's really weird that it's doing this to my engine over a year after i've been driving with the 34 code. But it would totally make sense, the ecu is trying to adjust my timing to compensate/fix the rod knock... but the sensor keeps reading that it's knocking.

I'll report back when I install the sensor. I've seen a few unsolved posts about this problem so I'll try to clear up some of those future questions.

[big monkey racing]

Have you tried the simple things like check your air filter, inspect/regap plugs, ect. most problems ive encountered usualy have a simple fix. Also i don't understand that if you test a sensor and it passes then y replace it. if its good then a new one wont do you any good but support your local parts store. ive learned this one the hard way

[zachattack_5491]

Have you tried the simple things like check your air filter, inspect/regap plugs, ect. most problems ive encountered usualy have a simple fix. Also i don't understand that if you test a sensor and it passes then y replace it. if its good then a new one wont do you any good but support your local parts store. ive learned this one the hard way

Oh nope I forgot about my air filter hahaha, yeah dude I checked all the small stuff. I might go pick up some new plugs though, the ones I have are the ones with the two things that create the spark (sorry for my lack of plug knowledge lol) so I don't think you're supposed to gap those.

Which sensor are you referring to? The o2 didn't pass the test. The FSM says it should switch between rich and lean at least 5 times in 10 seconds. It didn't, so I replaced it. I later found out that the o2 was actually reading correctly... which meant it was something with the engine. My local autozone isn't very strict on the returns so I might just clean it off a little and take it back lol.

[big monkey racing]

ok i must have miss read that but to have it suddenly happen what changed prior to the problem occuring?

[zachattack_5491]

ok i must have miss read that but to have it suddenly happen what changed prior to the problem occuring?

I know, it's really weird that it happened out of no where. It had been raining a lot for a couple days, I had been making weekly 130 mile trips back home (twice), and I started putting regular unleaded in instead of premium because of the long trips. Other than that, nothing out of the ordinary happened. It did backfire a couple times before it started raining, so I don't think the rain caused it.