Causes of Bogging after Operating Temp

[Matt_240]

My car bogs. bad. around after 15-20mins of driving and car reaches operating temperature. buckles, chokes, fuel cuts, you name it, it does it.

i know there is closed loop/open loop. what are the components that change after closed loop?

i know the o2 sensor is one. anything else?

Any help is appreciated.

[Matt_240]

any advise would help. thanks

[Al_S14]

waht year is your car? does power suddenly drop off when you haul ass then return moment later and jsut pick back up as if nothing happend?

it seems i got same problem but nobody seems to know the fix

[IvanAtSPRacing]

Your car will run on an open loop program untill it reaches normal operating tempature. It switches to closed loop at this point. It relies on feedback from the O2 sensor at this time. If the O2 sensor is not reading right, then your car wont run right. Does your car run ok at WOT once up to temp? At WOT the ECU switches back to open loop and doesnt use the O2 for adjustments.

[sciamop]

It takes 20 minutes to reach operating temp in Hawaii? IIRC, you can just unplug the 02 sensor and the car will be in open loop mode = bad gas mileage but better than junk signal.

My car acts this way sometimes too. I'll be troubleshooting it in the spring... I'll post my findings.

Todd
93 Coupe
91 SE-R

[Matt_240]

i know the o2 sensor isnt' the only thing. the coolant temp, and other things are relied upon in closed loop as well.

when it starts bogging like that, i will disconnect my 02 sensor and see if that works. in the meantime im gonna change my ecu and coolant temp sensoor.

any other suggestions as to what it could be? thanks for the help guys. im sure lots of people have this same problem.

[KOUKI KA-T]

Guess I'll ask the obvious..... throwing any codes?
I had a similar problem once, got hot enough in the engine bay to melt the 02 sensor plug and cause a short. Threw the entire ECU program out of wack and the car would shutdown randomly, sometimes not idle etc. Had to go through the all the fuses and replace the ones that went and it was that simple. Had me stumped for a while as I didn't notice the plug had been melted on the side...

[Matt_240]

Guess I'll ask the obvious..... throwing any codes?
I had a similar problem once, got hot enough in the engine bay to melt the 02 sensor plug and cause a short. Threw the entire ECU program out of wack and the car would shutdown randomly, sometimes not idle etc. Had to go through the all the fuses and replace the ones that went and it was that simple. Had me stumped for a while as I didn't notice the plug had been melted on the side...

so you just replaced the fuses and o2 sensor??

[KOUKI KA-T]

so you just replaced the fuses and o2 sensor??

02 was fine, just had to cut off the melted plugs and solder the wires, then replace a couple fuses that blew from it all.
So are you throwing any codes???

[Matt_240]

code 55. crap.

i guess i gotta check all the wiring and sensors. =P

[KOUKI KA-T]

code 55. crap.

i guess i gotta check all the wiring and sensors. =P

Ha, no malfunction.
Definitley not the same problem as me then, mine threw more than 12 different codes (I just stopped counting after it flashed the 12th one and checked all the fuses and found my problem.)

[Al_S14]

o this is driving me insane! i've replaced every part of ignition system except for the distributor coil...anyone have this part fail? and since i am not getting any codes i am like a blind man trying to shop.

i dont see how this could be a misfire since CEL never comes on and this happens to me on every dive cyle(since my driving style is umm well suicidal).

can knock sensor be faulty and fuck with my timing thinking engine is about to blow. same as matt this happens only when car is hot (or when it's cold and it happens its not nearly as severe as when hot)

[KOUKI KA-T]

o this is driving me insane! i've replaced every part of ignition system except for the distributor coil...anyone have this part fail? and since i am not getting any codes i am like a blind man trying to shop.

i dont see how this could be a misfire since CEL never comes on and this happens to me on every dive cyle(since my driving style is umm well suicidal).

can knock sensor be faulty and fuck with my timing thinking engine is about to blow. same as matt this happens only when car is hot (or when it's cold and it happens its not nearly as severe as when hot)

How is the idle? Does it seem like the car runs on 3 cylinders?

[Matt_240]

idle is perfect on my car. just when hot, extreme bogging. sucks

i have a feeling it has something to do with our wiring harness or sensors. either ground is faulty somewhere, sensor is going bad, or just old harness crapping out.

keep the suggestions coming. we need all the help we can get cause no one seems to know whats wrong. thanks!

[Yuri]

Wow, my car has the exact same problem, but it is totally random, like sometimes it will happen right after startup, and then it will come and go. I spoke with someone at Bulletproof, and they said it's probably the airflow meter. The Nissan dealer agreed with this. I'll wait to see if the O2 sensor fixes your problem, so keep us up to date..

[Al_S14]

car idles likr shit.....well its smooth but whole car vibrates(um thats almost an oxymoron but you know what i mean) like it misses.
doubt its maf... usually it either works or doesnt. if maf dont work car will not run at all. plus you got to remember dealer will tell you anything to get you in the shop and paying the diag fee only then they will focus on finding the real problem. its always "its proalby your XXX but i got to look at it first" .
cant be teh 02 either(if were all talking about same problem) it just dont have this much effect on performance at WOT...if any at all
i've come to a conclusion it's the coil that cant put out at high load which make sence. as car heats up resistance increases making things even worse preventing faulty coil to produce enough spark...and it misses. shoping for a used distributor now ill let you know how it goes

[Matt_240]

distributor? i dont think thats it.

Im borrowing parts tomorrow... coolant temp sensor, o2 sensor, and throttle position sensor. i'll let you guys know how that goes. if these are not it, im almost sure that its the harness.. maybe bad ground somewhere. we'll see..

[idlafie]

My car bogs. bad. around after 15-20mins of driving and car reaches operating temperature. buckles, chokes, fuel cuts, you name it, it does it.

i know there is closed loop/open loop. what are the components that change after closed loop?

i know the o2 sensor is one. anything else?

Any help is appreciated.

When your bogging problem occurs, does it occur during acceleration and braking? Do your dash lights come on & the engine dies on you or seems like it's gonna die on you??

If you are getting weird symptoms like the above, check the ground connections on the rear driverside portion of the engine block right above the O2 sensor. Nissan in their ultimate wisedom grounds several components at that point - fuel pump/distributor coil/etc. If one of those ground wires goes bad, (and it can, remember it's right above the exhaust manifold where it gets really hot - heat & wires are not a good combination - wire connections get brittle & break), then you could have an intermittent short in one of your ground wires. Easiest way to fix it is find a new grounding grommet & cut the existing one off & solder all the ground wires to your new grommet. That should fix your bogging problems.
Anyhow, hope this helps...
ID

[Matt_240]

When your bogging problem occurs, does it occur during acceleration and braking? Do your dash lights come on & the engine dies on you or seems like it's gonna die on you??

If you are getting weird symptoms like the above, check the ground connections on the rear driverside portion of the engine block right above the O2 sensor. Nissan in their ultimate wisedom grounds several components at that point - fuel pump/distributor coil/etc. If one of those ground wires goes bad, (and it can, remember it's right above the exhaust manifold where it gets really hot - heat & wires are not a good combination - wire connections get brittle & break), then you could have an intermittent short in one of your ground wires. Easiest way to fix it is find a new grounding grommet & cut the existing one off & solder all the ground wires to your new grommet. That should fix your bogging problems.
Anyhow, hope this helps...
ID

it only occurs during accelration. and it seems like its gonna die cause it jerks so much but if i accelrate through it, its ok sometimes. yeah, the ground connections by the manifold are definitely a possibility. where should i cut the ground wires from though?

thanks for the help

[KOUKI KA-T]

car idles likr shit.....well its smooth but whole car vibrates(um thats almost an oxymoron but you know what i mean) like it misses.
doubt its maf... usually it either works or doesnt. if maf dont work car will not run at all. plus you got to remember dealer will tell you anything to get you in the shop and paying the diag fee only then they will focus on finding the real problem. its always "its proalby your XXX but i got to look at it first" .
cant be teh 02 either(if were all talking about same problem) it just dont have this much effect on performance at WOT...if any at all
i've come to a conclusion it's the coil that cant put out at high load which make sence. as car heats up resistance increases making things even worse preventing faulty coil to produce enough spark...and it misses. shoping for a used distributor now ill let you know how it goes

another thing that causes the shitty idle and bogging like it's running on 3 cylinders is a torn lower o-ring on the injectors. If there's a slight tear or nick in the o-ring fuel just dumps on through and can be so bad it drowns the spark causing it to bog like all hell.
start your car and let it idle. unplug one injector at a time and see if there's one you unplug that has no effect on idle. I think yours is a fuel/spark problem.

[Al_S14]

distributor? i dont think thats it.

Im borrowing parts tomorrow... coolant temp sensor, o2 sensor, and throttle position sensor. i'll let you guys know how that goes. if these are not it, im almost sure that its the harness.. maybe bad ground somewhere. we'll see..
coil which is built in to the distributor not the distributor itself

[Matt_240]

coil which is built in to the distributor not the distributor itself

ok. let me know if that works.

i put in a new cts and o2 sensor. but im in denial of driving it. haha. cause i doubt it fixed the problem. i'll let you guys know tomorrow. but if it is the distributor then that would be an easy fix.

[Prelude Guy]

I have the same problem with my 89 240

Changed:
O2 sensor
fuel filter
Plugs
Wires
dist. cap
rotor
CTS
new ground wire
new catalytic converter
new fuel pump
new TPS
checked the MAF (fine)
checked the ignition coil (fine)
new oil
injector cleaner
new alternator (with my old one, the batt. light would light up a little)

STILL bogging. :ugh:

Let me know what you find out.

I am going to try swapping out my ECU with my friend's and clean the EGR valve. Other than that, I will have to to take it to a shop. :( I've been fighting this for 5 months now.

[Matt_240]

well, if changing the cts and o2 sensor doesnt work out for me, im gonna straight change the whole wire harness.

[Al_S14]

Prelude Guy, how did you check your coil? just check for resistance ... was it when hot or cold ? if its an intermittent problem with a coil it will test fine everytime except for that instance when car bogs(but that cant be check while driving ...)

[monkeyspeed]

check the timing

[Matt_240]

change the cts and o2. no change.

gonna replace part of the harness next. also, switch out distributors. will update.

[Yuri]

What kind of engines does everyone have? Mine is an SR that I'm experiancing the problem with. I had the wiring harness thoroughly checked and repaired, replaced a bad coil, and replaced a clogged cat. It still bogs...

[Matt_240]

ok, sent the car to an electrical shop to redo part of the harness.

will update.

[idlafie]

it only occurs during accelration. and it seems like its gonna die cause it jerks so much but if i accelrate through it, its ok sometimes. yeah, the ground connections by the manifold are definitely a possibility. where should i cut the ground wires from though?

thanks for the help

Your problem occurs ONLY during acceleration?? Could it be possible that your car is NOT getting enough fuel or air mixture??. Could be a screwed up fuel pressure regulator OR vacuum line running to it or a lagging fuel pump. Maybe even PCV valve..who knows...
What RPM band does your problem seem most apparent? Does it clear up when you go to Wide Open Throttle? Your bogging could be due to a stuck EGR valve or carbon buildup in your EGR valve or a clogged line that runs behind the EGR to the exhaust manifold.
Troubleshooting this problem is gonna be a royal BEOYTCH!!...Find yourself someone extremely knowledgeable in tuning 240's...you're gonna need their expertise!!
Anyhow, hope this helps..
ID

[Matt_240]

Your problem occurs ONLY during acceleration?? Could it be possible that your car is NOT getting enough fuel or air mixture??. Could be a screwed up fuel pressure regulator OR vacuum line running to it or a lagging fuel pump. Maybe even PCV valve..who knows...
What RPM band does your problem seem most apparent? Does it clear up when you go to Wide Open Throttle? Your bogging could be due to a stuck EGR valve or carbon buildup in your EGR valve or a clogged line that runs behind the EGR to the exhaust manifold.
Troubleshooting this problem is gonna be a royal BEOYTCH!!...Find yourself someone extremely knowledgeable in tuning 240's...you're gonna need their expertise!!
Anyhow, hope this helps..
ID

i capped off my egr. but i will look into the fuel pump/fpr

wire harness didn't change anything.

[Prelude Guy]

Can you give any details on how to take off and cap off the EGR valve on a KA24E motor?

I am having the same problem. It happens when the car is cold too though.

Thanks,

Andy

[Matt_240]

prelude guy - just remove egr system. cap off all vacum lines. put a plate over side by the intake and plug the exhaust manifold side with a screw-on closed end/bent pipe.

weird thing.. after yesterdays fixing of part of the harness, i decided to check the ecu again for codes. and guess what? this time it wasn't 55.

i got 12 - Maf
32 - Egr
82 - Crank Position Sensor

I have a couple mafs to switch out so i'll try that. I know why the egr code is shooting out (because i dont have one). not sure about the crank position sensor though. isnt it in the distributor? uh... i'm gonna look into that. i have an extra distributor lying around anyway.

will update again.

[Matt_240]

oh crap, nevermind. crank position sensor was behind the motor. it was the camshaft position sensor thats in the distributor.

[Prelude Guy]

prelude guy - just remove egr system. cap off all vacum lines. put a plate over side by the intake and plug the exhaust manifold side with a screw-on closed end/bent pipe.


Are there only 2 bolts holding the EGR on? Those are the only 2 that I see.

Can I use a piece of aluminum to cap it off?

Thanks for the help. I hope you figure it out.

Keep us posted. :)

Andy

[idlafie]

i capped off my egr. but i will look into the fuel pump/fpr

wire harness didn't change anything.

HUH?? What did you do THAT for?? Did you know that your ECU programming takes into consideration that exhaust gases from your EGR are SUPPOSED to be recirculated back into your intake manifold to assist with engine management AND pollution control?? If the ECU isn't finding those recirculated gases the ECU will try to compensate for this. And as a result of this, your engine performance will suffer...as you are now discovering. Did your bogging problems start before OR after you disconnected your EGR?? If it was before, then your problems were due to a defective sensor and NOT your EGR. Just because a sensor isn't throwing a code, doesn't mean it hasn't gone bad. With today's modern engines, and their electronics/sensors, troubleshooting the problems are becoming more & more difficult. Trouble codes help but aren't exactly right at times.
Don't believe me?? Then read the following article posted by a pro...
http://www.asashop.org/autoinc/july2002/techtotech.cfm
Anyhow, hope this helps...
ID

[Matt_240]

yeah, only two bolts

im stumped. changed maf to no avail.

gonna check my fuel pressure next.

[Matt_240]

f*ck it. im tired of this ka motor. im gonna go sr.

[Yuri]

Ummm, SR's do it too..

[Prelude Guy]

I know how you feel, Matt. I am searching for an SR fornt clip too even though I can't afford it right now. :bash:

[Matt_240]

i know what the problem is. its my harness. did the giggle test and my car bogs...this is after full operating temperature.

but im tired of the ka motor in general. its time to step up for me.

but to test if its the wire harness, after it starts bogging constantly, stop somewhere, open your hood and giggle your harness around in different places. for me, its probably the injector harness.

good luck guys

[Al_S14]

didnt you say some shop redone your harness?
and whats suppose to happen once i "open your hood and giggle your harness around in different places" ?

[fliprayzin240sx]

Im willing to bet that its your water temp sensor. My car had the same issue. basically, ecu thinks its running cold so its dumping more fuel that its supposed to at operating temp causing you to bog.

[Al_S14]

why does it do it only in high rpm...above 4/5k . if it sprays more fuel then needed it will jsut run rich not misfire hmmm

and if ECT was faulty wouldnt engien temp gauge read wrong?

[Maxtype 240]

why does it do it only in high rpm...above 4/5k . if it sprays more fuel then needed it will jsut run rich not misfire hmmm

and if ECT was faulty wouldnt engien temp gauge read wrong?

Coolant Temp Sensor (CTS) and the cockpit temp gauge are 2 different sensors.

The best way to check CTS is an OBD scan tool for 95-98 cars...

Jesse

[Al_S14]

yeah i was jsut about to tell you about it... did it this morning with Honda PGMTester. its working to spec . still need to check fuel pressure and coil , hope its one of those 2

[eurosil80]

my ka24e has the same problem...except now....it floods when i shut it off....and wehn i come back to start it it wont start up the first couple of cranks.... The temp sensor seems logical...ill give that a try.... what are the main causes of floodin?

[Matt_240]

didnt you say some shop redone your harness?
and whats suppose to happen once i "open your hood and giggle your harness around in different places" ?

oh, they just redid a small section. not the injector wires cause they still "looked" ok. but most likely its not.

when car is bogging, pull over and giggle harness around. it will bog your car down if something is wrong. try just moving stuff around. see if you stumble onto a vacumn leak or bad section of your harness.

[Al_S14]

my ka24e has the same problem...except now....it floods when i shut it off....and wehn i come back to start it it wont start up the first couple of cranks.... The temp sensor seems logical...ill give that a try.... what are the main causes of floodin?
leaking injectors is usually.

now that you mention it i noticed that it take lot longer for it to start even with my batt at 600cca.

wierd thing this is the boggin issue has been gettign better and better...when i first got the car 5k ago it was doing it in 2nd gear and loosing power consistently .... now it seems to happen mostly in 3rd at 5k plus . overall its much less severe now . takes longer for shit to happen :bash:

[trixxxr4_kids]

well maybe it means your motor just cant do it anymore , is the fuel delivery good? fuel filter or injectors maybe the rail , the pump, or did you do anything that would pinch a line? and if its turbo you might have a boost leak somewhere , a bad maf, or a Blow off valve that might get stuck open :ughug:

[Yuri]

Mine seems to have been a turbo that wrenched itself loose from the manifold. I won't know for sure until tonight.

[DrSiD202]

my car boggs in every gear right at 4k rpm .. i'll watch your thread till you find an answer. everyone i know is baffled by my problem.

maybe ill start my own thread, noone has posted in a month, here.

[c0axiL]

i drove a dsm that had a similar problem. it started off fine but once it warmed up it the problem started. checked the whole ignition system and most of the fuel system but they didnt work. after a while of driving it like that it became a constant problem even when the car was cold. it ended up being a problem with the plug wires, even though when they were current tested they were fine. im not sure if this can help you in anyway, but good luck wiht your prob.

[SxMachine]

Has anyone found a solution 2 this prob yet i'm having similar issues. I've replaced injectors, fuel filter, fuel pump has around 1K miles, distributor cap, plugs, and wires so far. Whats left that u guys haven't tried?

[F3600]

Did you check, tested the water temp sensor ? Its a simple procedure in the FSm give it a look

[Al_S14]

Has anyone found a solution 2 this prob yet i'm having similar issues. I've replaced injectors, fuel filter, fuel pump has around 1K miles, distributor cap, plugs, and wires so far. Whats left that u guys haven't tried?


well i fixed my problem. dont know how it happend but my car was nearly 15 degrees off timing. maybe previous owner replaced the distributor and didnt sent it correctly but it more then fixed the problem. first time i drove it after taht it was liek a new car .... got an awesome kick in the pants in first. almost like Vtec but now that i've had it running right for few weeks it doestn feel as quick.

[Yuri]

Mine ended up being a blown turbo gasket. On both sides of the turbo!

[ledzeppelin240]

I would check the ingition system, fuel, and O2 sensor. If everythig there checks out test the EGR valve and EGR control valve, then make sure the wiring harness where it connects to the ecm has a good connection. The CAS is located in the distributor just to clear that misinformation up. It uses an LED and a photo diode to transmit a digital signal to the ECM.

[einherjar]

My car bogs. bad. around after 15-20mins of driving and car reaches operating temperature. buckles, chokes, fuel cuts, you name it, it does it.

i know there is closed loop/open loop. what are the components that change after closed loop?

i know the o2 sensor is one. anything else?

Any help is appreciated.


Hey Matt
Did you fix the problem? if so, what was it? :S