Car running lean, slow

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dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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I just recently replaced -O2 Sensor-Battery

She was running rich and wouldn't pass smog so I changed out the parts above and she passed.

Checked spark plugs and on the very tip they are white. I think this means she is running lean.

Typical Day - I start the car after shes been sitting for about 10-12 hours. She sounds good, idles fine. Starting in first is smooth no problems, power is all there and everything. I commute 30 miles one way to work and theres lots of traffic so I'm usually driving for about an hour. I make it to work and the car seems fine. When I come home I make a stop after shes warmed up, start her up again and now when I start off the clutch/flywheel Chatters like a *****. It chirps the tires sometimes. (This doesn't happen when the engine is cold or somewhat warm). Then when I go to hit the gas, maybe half throttle or full (doesn't matter) I get this delay then it takes off then after about 3k to 3.5k I have no power. Its the equivelant to 1/8 throttle and it should be WOT. This happens in every gear except 5th it seems, This can happen either until i get home or sometimes the car "wakes up" after like 30 mins. Then I will have full power again.

It's very wierd and TBH it's driving me nuts!

Also the car bucks around when I get on and off the throttle. Motor/transmission bounce like 2-3 times when I get on and off the throttle. I just replaced motor mounts (nismo). It was really smooth at first then it started bucking. I'm not sure if these 2 issues are related.

Another issue that MIGHT be related. I'm running a 1000 watt rockford amp with a 2 farad cap. Randomly the power will be cut from both the cap and the amp. My driver side window wont work and thats when my car is slow.

I sat down and thought about this with my father, we both have minimal experience with cars. We seem to think it's either the fuel filter, fuel pump, or possibly the MAF. The amp issue I have NO IDEA, All the grounds seem straight.

Let me know what you guys think.. Sorry about the story. THANKS!


kermitman
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Your amp could be drawing more power than your alternator and battery are capable of producing. If this is occurring, then there probably isn't enough current to properly run the ECU and all of the sensors properly (MAF,TPS, Etc.) First thing I'd do, would be to disconnect the amp and see if it effects the performance. if it does, then I'd check all of your grounds and have your alternator and battery tested.

If this doesn't fix it, then check all of your vacuum lines and then your MAF and TPS voltage. If your tps went out then it could explain your problems with WOT. Search the forum for a procedure to check MAF with a Multimeter.

Clogged fuel filters are cheap to replace. Fuel pressure and flow can be checked by most mechanics, or if you have the pressure gauge do it yourself. idle psi should be 45 psi and wot should be 90 or so.

I doubt it's your fuel pump, because your car would stall out without fuel. How's your gas mileage since the O2 sensor change

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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Before and after the O2 sensor change I've been getting 24.5-25 average... When I felt the car running lean I averaged 27.5 mpg This last fill up I averaged 24.2, but there was a lot of near WOT. Yea that makes a lot of sense about the amp pulling too much. I love my music but for the sake of performance I guess I could go a couple days to test, without it. I drove to work today and its been good so far. See what happens when I drive home.

Any idea why the clutch/flywheel would chatter only after the car is completely warmed up?

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wilfonzo
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Car: s14

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wow! the first lean 240 i think... there is about 10000 posts about 240's running rich

dubbs693
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Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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I unplugged the ecu and then plugged it back in. I also moved the connector for the power connector for the amp to make more contact on the terminal. So far.. 1.5 days of goodness.

Only thing shes still chattering like a ***** only when really warm.

Also

Shifts are rough and so is getting on and off the throttle.

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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I replaced my fuel filter with a z32 filter. The car seems a lot smoother.

The car has performed well over the past 2 days. This possibly might have fixed it. I'll keep you guys posted.

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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Ok, now I am REALLY starting to get frustrated......

I've replaced the following

BatteryGroundsO2 sensorIntake filter (Cold air Intake)Cleaned the MAFFuel Filter (z32)Changed out with another ECUcleaned DIST CapChecked spark from ignition

All seems good

This is my theory... I have an audio system.. 1 amp with 2 subs. I have a CAP inline from the battery to the amp. I'll have the Stereo off or on (doesn't matter) and the CAP will start to beep, indicating it has lost power. Then it turns off along with the amp (if its on) Sometimes it will kick right back on and sometimes it stays off for a while. It always comes back full power though.

My battery shows 14 V when first started. Roughly 13.5 after an hour of driving. I show the same at the CAP when it is working. Being as this is random i dont have the oppurtunity to test the cap while its beeping... Because the CAP only looses power while I am moving. I did notice it once while it was beeping the Voltage readout read 8V.. Which is not good.

MY huge question that I am begging you guys to think about. How in the world can this be happening? I sanded down the paint on body for the amps ground. NO PAINT AT ALL. I used the Seatbelt bolt and a 2 ft ground.

My o2 sensor is about 4 inches away from the exhaust port on the block is this ok? Its on Pace Setter header (I know they suck i bought the car with it.) I also have an injen cold air intake which is a foot off the ground and a straight through borla exhaust. Theres only 1 o2 sensor correct?

I think my performance issue and the amp issue are related somehow. They don't happen at the same time though. I don't want to bring it somewhere because of the randomness of the issues. Thanks for reading.

lilschmitts
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Joined: Mon Jul 10, 2006 11:56 am

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from my experience with using caps they can be more of a headache than a blessing. cause now instead of your alternator having to only power the battery it has to charge both the cap and the battery because in essence the cap is another battery. and if your using a huge amp its gonna be using alot of power and causing huge strain on your alternator/battery.

if nothing else works and u still think its your system buy a high output alternator and im guessing it will solve your problems.

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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Ok, I took out the CAP, Took out the AMP and i replaced the spark plugs and wires.... She is still running slow.. I'm going the replace to DIST Cap next.

One thing i noticed.. as my Cold Air Intake is on top of the radiator, the pipe gets really hot. Could hot intake temps cause me to lose that much power? Its been really hot out and I've noticed it more with the heat. What do you guys think?

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ricebike
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hmm, no trouble codes?

I think your clutch is starting to go... or the hydraulic system... check those as well

dubbs693
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Car: Red 91 s13 Hatch

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I've replaced my clutch b4 and I know the difference between a slipping clutch and a slow engine.. When the clutch slips the rpms jump and u can actually feel the slipping. This accelerates at a constant rate, just slow. No CEL and what do you mean by hydraulic system? The lines and master/slave cyl for the clutch?

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ricebike
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ya, but since u know that difference between the 2, then this may not be it...

check trouble codes just to be sure... i thought only the CA emissioned cars came w/ the check engine light... (well in the SOHC KA24E case anyways)

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tiger
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maybe you shoudl just take your music stuff out for a bit and see if it is causing the prob... hey, I love my music too.. I only hae a 600watt 4 channel and one 12 sub. just take it out for a sec to see.

dubbs693
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Car: Red 91 s13 Hatch

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Its been out for 4 days... Still ****ed

Seems to be heat related.. Even though the temp gauge never goes past 1/3

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tiger
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just check your trouble codes... u never know if your cel bulb is blown out, If anything goes wrong with my car, the first thing I do is check the ECU... then go to step 2..depending on the problem/symptoms. If you get a 55, that means that all of the sensors are coming back a. o.k. :-)

dubbs693
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Car: Red 91 s13 Hatch

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The CEL that i have is just a dummy light.. I know it works cuz its on wen i turn my key to ignition... so, my noob question is.. how do i check the ECU trouble codes.. should the key be on accessory or ignition or off ? thanks

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tiger
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get yourself a flathead screwdriver... go to the passenger side kick panel.. take it off... there you will see the ECU... put your key in the ignition and turn it all the way until if you turn it any more you will try to star the car... you should see a red LED light on the ECU lit up. take your flathead and turn the dial all the way counter clockwise, wait 2 sec... then turn it back the opposite direction.. then you will see flashing lights.. if you se 5 slow flashes and 5 fast flashes, that means everything is good to go! If you see something different... go to http://www.240sx.org and look in articles.. you swhould see the trouble code index.

dubbs693
Posts: 114
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Car: Red 91 s13 Hatch

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u = the man.. I'll check it out when I get home.. Thanks

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ricebike
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Car: 1989 240sx se 5spd (donated to my brother in law)
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dubbs693 wrote:u = the man.. I'll check it out when I get home.. Thanks
dudette!

& another dartboard; when u replace the clutch/ did u do the rear main seal? oil may be leaking past it & may cause the chatter? but that'll happen most of the time & not warm... are u sure u got the clutch pedal adjusted properly as well?

oh more direct links to finding trouble codes for your car/ dunno sohc or dohc so I'll link both from the FAQs section:

SOHC

DOHC

don't forget to d/l the free FSM in my sig link as well!

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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yea i didnt know tiger, sorry.

Ricebike,

I'm pretty sure, it engages fully about 3/4 travel..

180fan
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For a lean situation that seems to have more of a temperature related issue, I would have checked out the cts.

So do the revs climb normally and the car not move all that much at all? Or does the car just plain and simple rev up slowly and move slowly?

Next thing, is how is your timing? Retarded or advanced timing can cause your car to run like feces as well. How about a tune up? When was the last time you did that? Hit us up with some of the background on the maintainence history of the car.

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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CTS?

The revs climb slowly and the car accells slowly

I am going to check the timing this weekend wit a timing light.

The engine was rebuilt 7k miles ago

This is what I've replaced since about 1k miles ago

o2 sensorplugsplug wiresbatterygroundsECU

I have some connectors dangling

Also there are some resistors that i need to snap some pics of and show you guys, because I am not sure what to do with them.

180fan
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Car: 89 fastback

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coolant temp sensor

alrighty if it's slow on the rev and slow on accel, then probably not a clutch issue, but an engine issue.

What resistors do you have put in and where?

dubbs693
Posts: 114
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Car: Red 91 s13 Hatch

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Since I have a Cold air intake and the PAIR is gone. On the line running from the MAF to the dist coil there is a resister there.. a loop of wire... Also by the fuse box there is a loop of wire... Ill snap some pics.. The reason I don't know what these are is that I bought the car like this.

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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The person I bought it from said its a 95 s14 engine with s13 cams made for an s13 ecu.

See the o2 on the header?? Is this ok.. Theres only 1 rite?If u can't read, it basically says.. What is this on each circle.This is on the Dist Coil.This is where the above plug fits into.. What does this do?fuse boxback of fuse box

Modified by dubbs693 at 5:32 PM 7/20/2006

Modified by dubbs693 at 8:10 PM 7/20/2006
Modified by dubbs693 at 8:10 PM 7/20/2006

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tiger
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dubbs693 wrote:yea i didnt know tiger, sorry.

Ricebike,

I'm pretty sure, it engages fully about 3/4 travel..
its ok! :-)

180fan
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Car: 89 fastback

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that thing on the far left in orange, thats a plug for the intake yes? The one at the top should be for your o2 senosr on your header. The one in the middle, is that the plug running up from the power steering line? Not sure about the plug on the far right though.

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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ok u kinda answered me.. above the pic I asked.. Is this O2 sensor location ok. Is there another before the cat? im guessing that orange thing on my intake and the plug in the middle are the AIV .. which is no longer there.. How bout the other **** with the fuse box and that connector on the DIST coil?

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tiger
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hey I think that other one goes to your dropping resistor... if you have one.. I dont think I can see it.. it should be right down from your ign coil if it's there.

dubbs693
Posts: 114
Joined: Tue Apr 04, 2006 5:24 am
Car: Red 91 s13 Hatch

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ok, so this weekend I replaced the Distributor Cap and Rotor, Still having the problem. I blew a exhaust gasket, so i replaced it, and its still leaking.

I checked the ECU and it gave me a trouble code of 3-4 then 5-5 Thats good right?


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