View Full Version : 240sx bogging
tman6500
06-03-2012, 07:23 PM
Mods: cat back exhaust, stage 2 clutch and light flywheel.
1995 240sx the car idles fine and under slow acceleration the car will rev up
but any acceleration past like 15% throttle the car stocks bogging really bad
and will die if not brought back to idle. No check engine light on. Last thing
changed on the car was the clutch and flywheel was about 4 months ago.
Things i have tried cleaned the maf,replaced fuel pump and filter,replaced plugs and wires,check ohms on injectors and pulled plugs off one by one but made the engine get worse,checked for vacuum leaks,checked fpr, hooked up fuel pressure gauge got 40psi idle 50 55psi when bogging, pulled exhaust off and ran just headers to see if the cat was clogged.
Any idea would be helpful
tman6500
06-04-2012, 06:45 PM
anyone with an idea?
Butcher240sx
06-04-2012, 10:56 PM
Ohm the knock sejsor, should be ~550k ohms. If not. Replace or bypass. Check fuel pressure. Check O2 sensor and CHTS.
ka4life87
06-13-2012, 12:25 PM
Did you mess with ur ignition timing or pull the distributor out? Also check intake system and make sure you have no leaks, ka's dont like any air leaks especially after the maf
tman6500
06-13-2012, 03:36 PM
checked the ignition timing which was good. Did a fog test over engine bay no leaks.
ka4life87
06-13-2012, 04:07 PM
Try cleaning the maf and check for possible loose grounds on the engine, if the ground on the rear left of the cylinder head is loose, it will cause a problem like that. The bracket that holds the o2 sensor wire also mounts there, possibly do a compression check also see if you dont have a burnt exhaust valve
tman6500
06-14-2012, 02:25 PM
Thanks for the help.
Replaced the Maf 2 days ago also I checking the grounds by removing them and removed any dirt/grim still the same. Guess i will try a compression check next.
Darren
06-14-2012, 02:35 PM
get a wideband o2, that'll help you determine if the bogging is caused by too much air, or not enough.
tman6500
06-19-2012, 02:52 PM
Put new distributor in and car now runs fine but when i press the pedal more then 50% the car picks up and then acceleration is very slow.
Butcher240sx
06-19-2012, 05:07 PM
Knock sensor. Did you check it?
tman6500
06-19-2012, 05:16 PM
No i didn't wouldn't that trip a code?
Butcher240sx
06-19-2012, 06:13 PM
Yes. But no check engine light.
tman6500
06-20-2012, 04:53 AM
K I will check out the volts and ohms today
tman6500
06-20-2012, 07:03 AM
Yes I still have the egr
tman6500
06-20-2012, 01:37 PM
So i got my hands on a scan tool and got P0325 and P0110 but when i went to reset the codes they were gone? Drove around for 30min checked and got code P0325 this time i stopped the car to reset it but it was gone again. PO325 is the knock sensor and PO110 is intake air temp right?
LOUD240
06-21-2012, 12:22 AM
replace the air intake temp sensor
Yes I still have the egr
I was going to say it might be sticking, but if you're getting codes for the AITS and knock sensor, change those... The knock sensor is easy if you fish it in with a coat hanger or something... You don't have to take your intake mani off like the FSM suggests.
Butcher240sx
06-21-2012, 03:28 AM
The knock sensor is troublesome on these cars. Bypass it
Butcher240sx
06-21-2012, 03:32 AM
/?/..................
tman6500
06-21-2012, 05:06 AM
Already bought both 100$ shipped
tman6500
06-21-2012, 09:16 AM
Thanks for the help everyone I will let you all know how it goes when the parts are in.
mr2gons14
06-21-2012, 07:39 PM
also something minor to check is ur plug gap make sure ur gappings are correct
tman6500
06-23-2012, 02:06 PM
Well both parts came in today installed them cleared the codes started it up drove it around and it did help a little bit but still doing it. The knock sensor was cracked down the side of it.
Butcher240sx
06-24-2012, 09:51 PM
Ever check the cylinder head switch? Injector seals?
tman6500
06-25-2012, 07:08 AM
What the temp switch? Haven't checked them yet
Butcher240sx
06-25-2012, 10:48 AM
Cylinder head temp switch. Two sensors on the front of the head near the rad hose outlet. One has one wire. That's for the temp gauge. The other has two wires. That's the cylinder head temp switch. If it goes bad it can make the car run real screwy. It's only about $8 .
tman6500
06-25-2012, 02:32 PM
I will take a look at it as always thanks for the help.
tman6500
06-25-2012, 04:17 PM
From the looks for where it is I might as well change the coolant or is the fluid level not up that high when not running.
Butcher240sx
06-25-2012, 04:47 PM
The coolant always does touch the sensor. When the car warms up and the thermostat opens . The sensor changes resistance with temp telling the ecu how to trim the fuel and timing. The one on my girls car was cracked, causing a high idle, hesitation and hot running. When you remove it not much coolant comes out.Dont use Teflon tape or any other sealant on the sensor.
tman6500
06-26-2012, 03:26 PM
Well I replaced the temp sensor and got new plugs and gaped them. The car sounds better but still does the same thing half throttle or wot the car bogs anything less car is fine idles fine revs all the way up fine. No check engine light or any codes.
Butcher240sx
06-26-2012, 10:31 PM
What's the tps voltage set at? Maybe take the injectors to get serviced and flow checked.
BONIN240SX
06-27-2012, 01:00 AM
anyone else think that maybe ohm/voltage checking the tps? mine didnt throw a code but i changed it and problems went away!
tman6500
06-27-2012, 02:01 AM
Tps is like 2 weeks old
Butcher240sx
06-27-2012, 02:11 AM
I'd start de looming the engine harness looking for brittle, burnt, or cracked wiring next. The temp sensor you replaced has two wires right, what voltage did you set the TPS for? Ever replace the o2 sensor?
tman6500
06-27-2012, 09:26 AM
Yes two wires on temp sensor. TPS was installed. By a shop would think they put it in right as the reading were bad on the original one. The o2 sensor I have never replaced.
nsfmike240
06-27-2012, 10:33 AM
sounds like a tps plug is unpluged or needs adjustment
tman6500
06-27-2012, 12:46 PM
I will check to see what the shop set the new TPS to. Im guessing I check ohms when closed and then open volts on power wire is what 5v and then ground?
tman6500
06-27-2012, 01:27 PM
Just checked the the o2 sensor got the car to normal engine temp and the computer said it was "open-loop" shouldn't it be closed when idle at normal temp?
Butcher240sx
06-27-2012, 02:14 PM
Yes it should be in closed. TPS voltage should be right under .5V . Back probe the middle wire and check the voltage. Mine is set at .45V. The O2 sensor is a service item to ne changed every 15K miles. It's only $15. I don't want to see you keep throwing parts at the car so hopefully that is it.
tman6500
06-28-2012, 09:34 AM
Going to replace the o2 sensor today.
tman6500
06-30-2012, 12:04 PM
O2 sensor in and car is sill doing it. The car runs better and starts right up fast now but still bogging. It it means anything the tip of the sensor was white.
Butcher240sx
07-02-2012, 12:19 AM
Any word on the TPS voltage? Are you absolutely sure you have no vac leaks? Was the mafs and dizzy new or used? Does it only bog under load or also when free revving in neutral?
tman6500
07-02-2012, 01:32 PM
Have not checked the TPS volts yet. Yes 100% no vac leaks mafs and dizzy are new. Yes only under load but fine revving in neutral.
tman6500
07-04-2012, 11:36 AM
So today i was checking all the basic things again some for third time and first i checked the injectors i just drove the car and now the car is cold the first 3 injectors were all around 11.8 .4 off was the most but the forth was at 15.8 then i tuned the engine on and put my ear on the end of a screwdriver which was on the injector could hear the clicking of all the injectors but that forth one. So i was guessing it was bad but after a drive around engine warmed up i tested them again all were around 12.8 and all were clicking like they were working. Could a injector work and sometimes not work.
Butcher240sx
07-04-2012, 09:21 PM
absolutely can change with heat. sounds like a bad injector. I thought so, thats why i recomended having them serviced and checked. grab a used one to check before running ot and buying a new one.
tman6500
07-05-2012, 09:23 AM
Any point in getting rebuilt injectors or are they not worth it.
cubaguy
07-05-2012, 07:19 PM
Seafoam! Jk
Butcher240sx
07-07-2012, 02:08 PM
I would start with one that you know is good and see if that is your problem. Might even be a bad injector driver in the ecu. Rebuilt injectors are fine too.
tman6500
07-07-2012, 02:28 PM
Taking a working one from friends 240sx on monday
tman6500
07-09-2012, 02:45 PM
The injectors in my friends car are 2 months old. Put in one working injector from friends 240sx and still doing it so I then put in the other 3 injectors. I can feel a power difference but still bogging at 50% throttle or wot. Still no codes or check engine light.
Butcher240sx
07-09-2012, 03:44 PM
did you lube the new o rings for the injectors? New o rings?
tman6500
07-09-2012, 04:19 PM
New o rings yes there was some lube on the injectors how much is needed?
Butcher240sx
07-09-2012, 06:06 PM
Doesn't take much lube. Really starting to sound like a wiring or ecu problem. Ignition timing is correct right?
Butcher240sx
07-09-2012, 06:08 PM
Make sure you are gettin good voltage at the injector clips.
tman6500
07-10-2012, 02:52 AM
Going out this morning it does it when I rev around 4k 4500k
tman6500
07-10-2012, 03:26 PM
Friend said it could be a sensor on the transmission?
Butcher240sx
07-10-2012, 03:40 PM
So its rpm based or throttle position based?
KiLLeR2001
07-10-2012, 03:58 PM
Whats your fuel pressure reading at? Could be a bad pump or bad wiring for the fuel pump. Check voltage going to the fuel pump.
tman6500
07-10-2012, 05:14 PM
Couldnt tell which it was will look more in to it tomorrow.
No fuel pressure gauge hooked up last i checked it was 40 psi at idle. Fuel pump is around a month old will check it out tho thanks
KiLLeR2001
07-10-2012, 05:26 PM
You need a dedicated fuel pressure gauge, fuel pressure will change after the car is warmed up. You'll especially want to see what your fuel pressure is reading around the problem RPM range. I'm not so concerned with the fuel pump but more so the connections / wiring for the fuel pump. A loose ground, wires with high resistance, will cause fueling issues for sure.
tman6500
07-10-2012, 06:01 PM
thanks for the help will check it out tomorrow and post the results.
tman6500
07-11-2012, 03:03 AM
Driving it around today it might not be rpm or throttle position its different for every gear and sometimes just goes limp in first from a stop
tman6500
07-11-2012, 04:57 PM
Do you mean the ground on the fuel pump like taking it out again? or is there another ground outside the tank?
tman6500
07-12-2012, 03:32 PM
The tps is set to .73 closed 4.23 wot
KiLLeR2001
07-12-2012, 03:34 PM
Not good. You'll want it at 0.45 closed.
tman6500
07-12-2012, 04:14 PM
So to change the voltage you loosen the two screws and move the tps unit?
KiLLeR2001
07-12-2012, 04:16 PM
Yes, make sure you test the entire range of motion as well. Move it and make sure the voltage continues to go up, if it dips down randomly or cuts out, you may need a new TPS.
tman6500
07-13-2012, 10:20 AM
Closed its .45 wot 3.97
KiLLeR2001
07-13-2012, 10:28 AM
WOT seems a little low, it should be around 4.45 - 4.55v.
Here's a good article: KA24DE : Checking TPS and adjusting idle : Nissan Articles (http://forums.nicoclub.com/ka24de-checking-tps-and-adjusting-idle-t161700.html)
tman6500
07-13-2012, 11:58 AM
set the wot to 4.5 and then closed was .97 now its set to .48 wot 4.04 best i could get it could it be bad it like a month old? It helped but still going it. Going up hill makes it bogs worse.
tman6500
07-13-2012, 02:44 PM
Going to hook up a fuel pressure gauge next.
Nizzan4u2nv
07-13-2012, 02:53 PM
Try swapping in a working ECU.
tman6500
07-21-2012, 08:57 AM
Well i gave up and a shop now has had it for about about 5 days no luck.
emack240StL
07-25-2012, 01:26 PM
Any word from the shop yet? I think mine is having the same problem that you are describing. I was happening earlier this year, I switched out the mass airflow meter, and the spark plugs and the problem almost completely went away, but now its getting worse again. I'm goning to start testing the advice from this feed, and see what works, but let me know what you learn from the shop.
tman6500
07-25-2012, 04:30 PM
They still have it cant find anything yet
tman6500
07-26-2012, 01:32 PM
Shop called and they ran out of ideas. Great lol now what
emack240StL
07-27-2012, 02:13 PM
I've been doing my research, I havn't had time to start palying with it yet, but one thing I have found that seems to give the same symptoms as we are experienceing is the EGR unit. It can go faulty, or get clogged and cause hessitations. The EGR and EGRV can be cleaned replaced or removed to fix the problem. Like i said i havnt tested it yet but you might want to try it, seems like its getting good results...
tman6500
07-30-2012, 02:44 PM
Checked the egr valve you can get your hand under it and push up on it and if the engine starts to idle bad (which mine did) then the egr valve is working.
Butcher240sx
07-30-2012, 04:01 PM
Did you ever try another ecu?
tman6500
07-31-2012, 09:39 AM
Couldnt get my hands on one to just swap. Might have to just buy one
OutlawLui
07-31-2012, 10:02 AM
Same thing with mine , it was a bad maf plug connection.
Thank god for safe mode
So i cut it off and did this
http://i278.photobucket.com/albums/kk86/evilpanamajack/smallmaf.jpg
Like a baws. now it runs perfect
tman6500
08-01-2012, 01:23 PM
Ya I was thinking about the same thing but didnt because i thought it would have given a code. I will have to steal or idea and give it a try thanks for your help.
emack240StL
08-01-2012, 02:20 PM
I just noticed last night that the air temp sensor on the intake just past the filter was missing the wires/pug that connects to the plug that goes to the ecu. i have the part on order and i'll let you know if that fixes my problem any. if you have and aftermarket intake u might want to make sure that yours isn't like this too. im thinking that when my maf went bad, the shop might have accidently knocked the wires of the sensor and it got lost somewhere and thats why only half of the problem got fixed the first time around in my case
tman6500
08-09-2012, 02:30 PM
Well bought a used ECU and no luck. Also hooked the MAF connecter right to the MAF nothing drove the car around don't see any difference. Wow this is crazy there most just be a loose wire or half broken wire sending a bad signal or something.
Butcher240sx
08-09-2012, 02:37 PM
Start de looming the harness. Wiggle test the connectors with a ohm meter to check for bad connections. I'd start with the Maf and work back. There is a gremelin in there somewhere.
falling angel
08-10-2012, 09:06 PM
One thing I haven't seen you check, the tps voltage. Does it go up smoothly all the way from closed to full open? I've had this problem, right at quarter throttle the voltage dropped then came back near 3/4 throttle.
tman6500
08-12-2012, 07:46 AM
Set the tps to .48 4.04 with the new on didnt see anything jumping in volts.
CraftHell
08-14-2012, 12:50 PM
Im having the same exact issue wtf..
tman by any chance is yours manual or auto?
tman6500
08-14-2012, 03:40 PM
My car is manual
CraftHell
08-14-2012, 04:07 PM
my car is auto but regardless the same issue.
this sound like yours?
Off the line, if i dont give it too much gas, it
stutters a bit, but if i give it a decent amount of gas, it seems to be
fine. Also, when i get around 2500 rpm's, the power seems to go away, this
happens all the way up till 3500 rpms. Once past there, it doesnt seem to
have any problems.
falling angel
08-14-2012, 09:34 PM
That sounds might similar to what my car was starting to do when the o2 sensor was starting to go.
tman6500
08-16-2012, 01:40 PM
O2 sensor is like 50 miles old max
tman6500
08-16-2012, 01:47 PM
First parks sounds around the same very light gas its fine any more it bogs. As I very slowly go through the gears (0-60 in 30 sec lol) it also wont go past 4k.
johara2320
08-16-2012, 03:49 PM
I had a similar issue and it was my distributor.
Highway Riding
08-17-2012, 06:00 PM
I had a similar thing happen to me just the past week. But i had so many different contributing factors from almost empty, hard turn etc... Car wanted to die then started idling like poo. Limped home filled her up and still not the best. Checked coolant and the reservoir was like almost bone dry. Filled it up with oem nissan coolant (green) and distilled water after 30+ miles i feel like she is normal again... Maintenance if fawkin key f me!
tman6500
08-18-2012, 11:16 AM
Already replaced the distributor
tman6500
08-23-2012, 09:17 AM
Well after checking everything and double checking still found nothing wrong. I just bought my friends motor that he built so old motor almost out new one going in.
Lazy706
08-23-2012, 09:33 AM
I had the same problem turns out timing was off by 1 tooth so I had to set the distributor 1 tooth off n that worked fr me
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