Car Honda civic 2008

High Negative Short term and Long term fuel trim All the time, Edakun help me

But because the longterm native fuel trim hasn't crossed -25%, my ECU is yet to set a p0172 code, but my fuel consumption had been bad affected, before I do 34mpg average, now I do roughly 26mpg, same route to work

Nurey, timifakay, autologic, kingreign, radautowork, trygo and all them gurus, I greet una

Kokomo:
Car Honda civic 2008

High Negative Short term and Long term fuel trim All the time, Edakun help me

But because the longterm native fuel trim hasn't crossed -25%, my ECU is yet to set a p0172 code, but my fuel consumption had been bad affected, before I do 34mpg average, now I do roughly 26mpg, same route to work

Alot of other stuffs and sensors needs to be checked to know why the fuel trims are the way they're.

What's your rpm when you took record of the MAF at 5.1 g/s, what's your outside temp also (what time of the day), also, what's your coolant temp reading, and your AF sensor readings in V at idle and at 2000rpm?

07034581213 send recordings to me let's chat from there.

kingreign:



Alot of other stuffs and sensors needs to be checked to know why the fuel trims are the way they're.

What's your rpm when you took record of the MAF at 5.1 g/s, what's your outside temp also (what time of the day), also, what's your coolant temp reading, and your AF sensor readings in V at idle and at 2000rpm?

07034581213 send recordings to me let's chat from there.

ok boss mi, will do that tomorrow, but in the meantime, here are some other screenshot I took during the week

@boss kingreign , here are the readings at various rpm as requested, I pull them from my OBD2 log

restrict

ok

radautowork help me nah

Clean the air filter
Clean the MAF
Do these first and provide feedback. Other suggestions are things that a professional will do for you.

Kokomo:
ok

You will find this very helpful.


https://www.youtube.com/watch?v=pIJdCZgEiys

EngRichie:
Clean the air filter
Clean the MAF
Do these first and provide feedback. Other suggestions are things that a professional will do for you.

I have change the air filter to a new one

I have use mass a flow cleaner to clean the mass airflow sensor


Still yet to be resolved

please gazzuzz, radautowork

aieromon:


You will find this very helpful.


https://www.youtube.com/watch?v=pIJdCZgEiys

thanks boss

miss the days when radautoworks take on challenge on nairaland... chai nairaland peeps stress that wonderful lady,,, she once help me tackle my airbag issues wonderful woman

@ Piyke i dont mind coming to your workchop oh,, grin lolework

Kokomo:
@ Piyke i dont mind coming to your workchop oh,, grin lolework

Well done boss. I don't have a shop o.

I remember having this same exact experience. Mine even went north of -19LTFT and tripped the P0172. There's no troubleshooting I didn't do: checked fuel pressure, examined injectors for leaks, etc. That was when I bought a compression gauge. Only to change where I bought petrol from, and voila, the thing started coming down on its own and the code left.
Our fuel here is legendary o. In the meanwhile, I suggest you change where you buy fuel from, and let's see.

Piyke:


Well done boss. I don't have a shop o.

I remember having this same exact experience. Mine even went north of -19LTFT and tripped the P0172. There's no troubleshooting I didn't do: checked fuel pressure, examined injectors for leaks, etc. That was when I bought a compression gauge. Only to change where I bought petrol from, and voila, the thing started coming down on its own and the code left.
Our fuel here is legendary o. In the meanwhile, I suggest you change where you buy fuel from, and let's see.

If have access to an advance scanner, let him reset the fuel to alcohol content in the ecu... And reset the fuel trim... But where to get that kind scanner na him he koko, can also flash the ecu to the latest or just swap it

Try this,

.

You can also check you egr in case it is stuck open.

My guess is since you don't have any mis fire and your car run smooth, it is most likely some raw fuel are getting pass your exhaust valve, during the exhaust stroke which the 02 sensor sees and interprete as a rich condition. This is due to the exhaust valve not properly sitted , meaning you need a valve clearance adjustment back to manufacture specification.

For Honda you have to do your valve clearance adjustment every 100k miles

Radautoworks, piyke, autologic and trygo can assist. These are good auto guys

Piyke:


Well done boss. I don't have a shop o.

I remember having this same exact experience. Mine even went north of -19LTFT and tripped the P0172. There's no troubleshooting I didn't do: checked fuel pressure, examined injectors for leaks, etc. That was when I bought a compression gauge. Only to change where I bought petrol from, and voila, the thing started coming down on its own and the code left.
Our fuel here is legendary o. In the meanwhile, I suggest you change where you buy fuel from, and let's see.

Yours is mostly a valve adjustment, that adjust itself, I guess your car was a Toyota.. But Honda valve clearance needs to be manually adjusted

hmmmm, i also read about the valve clearance adjustment back to specification solution, someone said it affect the manifold absolute pressure (MAP) which leads to high negative fuel trims

dicksonadams:
Try this,

.

You can also check you egr in case it is stuck open.

My guess is since you don't have any mis fire and your car run smooth, it is most likely some raw fuel are getting pass your exhaust valve, during the exhaust stroke which the 02 sensor sees and interprete as a rich condition. This is due to the exhaust valve not properly sitted , meaning you need a valve clearance adjustment back to manufacture specification.

For Honda you have to do your valve clearance adjustment every 100k miles

Radautoworks, piyke, autologic and trygo can assist. These are good auto guys

wow... I'm just now seeing this because it wasn't in my mentions till today because the "s" wasn't there...

Kokomo:
miss the days when radautoworks take on challenge on nairaland... chai nairaland peeps stress that wonderful lady,,, she once help me tackle my airbag issues wonderful woman

Comrade, issokay please


Off your mic


A high-powered committee has been set up to look into that incident and make recommendations to another 10-man committee which will review those recommendations and forward them to an implementation committee which will then implement those recommendations subject to the approval of course of an oversight committee which will be set up by a high-powered committee which will recommend suitable persons to serve on that oversight committee, subject of course, to an advisory committee that......


In fact Bros, just die the matter...the summary is that we are very much on top of the matter and will revert to you guys in due course

radautoworks:
wow... I'm just now seeing this because it wasn't in my mentions till today because the "s" wasn't there...

help me ma'am

Kokomo:
help me ma'am

just go to the shop. I don't give advice on here any more. It's unappreciated and exploited by the wrong people.

dicksonadams:


Yours is mostly a valve adjustment, that adjust itself, I guess your car was a Toyota.. But Honda valve clearance needs to be manually adjusted

Not correct. Car is a Honda.

Piyke:


Well done boss. I don't have a shop o.

I remember having this same exact experience. Mine even went north of -19LTFT and tripped the P0172. There's no troubleshooting I didn't do: checked fuel pressure, examined injectors for leaks, etc. That was when I bought a compression gauge. Only to change where I bought petrol from, and voila, the thing started coming down on its own and the code left.
Our fuel here is legendary o. In the meanwhile, I suggest you change where you buy fuel from, and let's see.

Bro , you are right oh, this issue is a very tough one to correct, I have been battling with it with the help of a techy friend, we have checked most of the sensors , even used lab scope to diagonise ssome more, no fault find thus far , yet my fuel trim LTFT and STFT are shooting above -17 to -20 all the time. Mehn it is crazy, I almost want to believe this is a problem that happen to all Honda with age.

Perhaps the car uses a higher octane fuel? I have tried other fuel station though.

I did read somehere (oyinbo Honda civic forum) that I might be able to correct it by getting a flashpro manager, a device that allows one to recalibrate the OEM ECU settings. I doubt if those can be found in Naija though

Kokomo:
Car Honda civic 2008

High Negative Short term and Long term fuel trim All the time, Edakun help me

But because the longterm native fuel trim hasn't crossed -25%, my ECU is yet to set a p0172 code, but my fuel consumption had been bad affected, before I do 34mpg average, now I do roughly 26mpg, same route to work

What error codes do you get when you scan?

Structuralman:


What error codes do you get when you scan?

I get P0172 at time, when I clear it , it doesnt re-appear till about a month. I notice slight misfire though, P0304 very rare, I think is due to the Rich condition.

I am considering a compression test on all the cylinders, hopefully it is not a case of worn or fauty engine due to rings or gasket.

Will keep the house update,

But if you have any other pointers, please assist

Kokomo:


I get P0172 at time, when I clear it , it doesnt re-appear till about a month. I notice slight misfire though, P0304 very rare, I think is due to the Rich condition.

I am considering a compression test on all the cylinders, hopefully it is not a case of worn or fauty engine due to rings or gasket.

Will keep the house update,

But if you have any other pointers, please assist

These are the possible causes for the P0304 code:

-Valve adjustment
-Faulty spark plug 4
-Clogged or faulty fuel injector 4
-Faulty ignition coil 4
-Fuel injector 4 harness is open or shorted
-Fuel injector 4 circuit poor electrical connection
-Ignition coil 4 harness is open or shorted
-Ignition coil 4 circuit poor electrical connection
-Insufficient cylinder 4 compression
-Incorrect fuel pressure
-Intake air leak

You will need a professional to do proper diagnosis.

Kokomo:


I have change the air filter to a new one

I have use mass a flow cleaner to clean the mass airflow sensor


Still yet to be resolved

please gazzuzz, radautowork

EngRichie:
You will need a professional to do proper diagnosis.

I paid a professional to do the job, we threw everything at it, las las nothing worked, we suggest another ECU , but all in all , had to give up and drive the car like that, the issue is a tough one, almost unsolvable...I think

Piyke:


Well done boss. I don't have a shop o.

I remember having this same exact experience. Mine even went north of -19LTFT and tripped the P0172. There's no troubleshooting I didn't do: checked fuel pressure, examined injectors for leaks, etc. That was when I bought a compression gauge. Only to change where I bought petrol from, and voila, the thing started coming down on its own and the code left.
Our fuel here is legendary o. In the meanwhile, I suggest you change where you buy fuel from, and let's see.

Hey bro, I change where I buy fuel but I still get high negatve fuel trim

Kokomo:


Hey bro, I change where I buy fuel but I still get high negatve fuel trim

Have you checked the following:
1. Leaking injectors
2. Fuel pressure
3. MAF
4. MAP
5. O2 sensors for laziness
6. Coolant temperature switch
7. Intake air temp sensor
8. Engine air cleaner element