95 Fuel And Carbon Build Up?

[gunat]

In that case, I'm experiencing the same thing. I'm running a little on the rich side but still there seems to be an unusual amount of carbon build-up as you mentioned. Washed my car last night and thoroughly scrubbed the exhaust. Will let you know the result after a day or two.

Please do- i remember having to only clean the exhaust every 2-3 months...

[GihanFX]

Ah the memories of that struggle! LOL!

lol, btw i also cleaned my exhaust today and well see how carbon builds, im runing only 95oct fuel,

[darinwrxsti]

Machang with regarding to subaru's in most cases i ve come across the air flow sensor has been the culprit, when it gets dirty the information sent to the ecu is quite questionable, hence it might get the ecu to increase its duty cycle of fuel through injectors which is basically firing more fuel when there is less air coming in. hence the car will run rich with a low AFR. But this is just a possible reason among many.Also i noted that you mentioned it went through a check up, so it could be something else even.

Also a nicely mapped or tuned turbo car will always run lean to a certain extent because the whole point is to extract the maximum amount of power through the available fuel and air.

But generally STI's do run rich thats why majority of them always shoot flames when they run open exhaust i.e without the cats

[STi B4]

Flames? More like BOMBS out of mine! LOL! Waiting on some toys for both mine and Jaffs cars to eliminate that.

[GihanFX]

Flames? More like BOMBS out of mine! LOL! Waiting on some toys for both mine and Jaffs cars to eliminate that.

ur car runing way too rich machan, thats why u hear BOMBS and flame coming out from ur exhaust

[GTAm]

I'm having regular carbon build up in the 156 throttle bodies. This has a serious effect on the performance. Had a very embarrassing moment when the car refused to climb a steep hill from standstill. The revs simply kept dropping. Not absolutely certain if it was because of the carbon build up or some other electronic glitch.

Will check all at next service which is now due.

My bro insists that there more carbon when he uses 95 and so has now switched to 90 for his 155.

Anyways recently I've been noticing the cars performance and response has been varying regularly. This could be the inconsistency of the fuel we are getting?

[GTAm]

Soltron smells WD40 for me and Yes I ran my old 504 diesel with soltron for couple of months. .............

OT.....but Hashan is your 504 Diesel an original?

[STi B4]

ur car runing way too rich machan, thats why u hear BOMBS and flame coming out from ur exhaust

Yeah and you love it! We'll miss it when we get rid of it

[Az]

I cant give any correct stats yet but I recently fixed a nano thingy to my car. First thing i ve noticed was lot of humidity coming from the silencer. (A sign of a good combustion). But i dont know for how long and its still early to give any fuel saving statictics. But for sure something is happening.

Nano fuel saver is a scam. It does not work, and it has no acceptable scientific basis. And yes... AlaGarden is selling those things. You mentioned X.1.R engine oil additive; that also does not work I'm afraid. Worldwide millions of dollars are robbed from the unsuspecting victims by these scammers.

Edited July 25, 2009 by Az

[GihanFX]

it seems theres someting wrong with out fuel, did less than 20kms today and alrealy noticable carbon buildup in the exhaust

[CARBON]

Actually, come to think of it........would this have started to happen maybe 3-4 months back for you Gunat?

Guys,

I had a similar problem as the car was taking a longer time when starting, this started only about 2 or 3 months back and as per the agents said it had to be the fuel.

But I have been constantly pumping 95 and always at a particular Ceypetco shed. During the last service few weeks back I got the MAF sensor and injectors cleaned.

Now problem is gone, but plan to continue with 95 with wurth just to be on the safe side.

[harshansenadhir]

OT.....but Hashan is your 504 Diesel an original?

wasn't that fortunate it was a converted with 1C engine coupled with the original gear box and drive train.

[STi B4]

Yep something fishy about the fuel. Even my car has carbon traces in the exhaust already.

[Kim]

After almost 10 months pumping 95OCT to d Allion, yesterday i pumped 90OCT (had enough reasons 2 do so) and i'm experiencing no difference at all, lets c if i am getting d same fuel figures. its lil less than usual since i'm taking d Dehiwala road and getting caught to d huge traffic in d morning..but still last week it had done 10.5, lets c. will be posting d results..

[gunat]

Please keep updating as and when there are more findings. I'm really keen to find out how many of us are seeing a difference...if this gets enough traction, maybe worthwhile a sticky...

[virensti]

I'm abit late in entering this topic but anyways we've been punping nothing but 95 from the time we got the vios in 07 Octobor. I dunno if there's alot of carbon in the exhaust but it seems fine at first glance. We've been pumping from the Horton Place,Palawatta and Laugh's Koswatta sheds. And this might be abit OT, but i got the fuel filter changed about 2 weeks ago and on inspection of the tank, the petrol is very very clear. No resedues or anything in the tank. Guy who inspected it was Bruce Nigel and he said we're pumping from really good petrol stations *touchwood* Will confirm about the exhaust carbon build up soon. At the moment car is running a very rich mixture due to a malfunctioning VVT Valve. 6800 bucks from toyota to replace it!

[Corolla121]

I'm abit late in entering this topic but anyways we've been punping nothing but 95 from the time we got the vios in 07 Octobor. I dunno if there's alot of carbon in the exhaust but it seems fine at first glance. We've been pumping from the Horton Place,Palawatta and Laugh's Koswatta sheds. And this might be abit OT, but i got the fuel filter changed about 2 weeks ago and on inspection of the tank, the petrol is very very clear. No resedues or anything in the tank. Guy who inspected it was Bruce Nigel and he said we're pumping from really good petrol stations *touchwood* Will confirm about the exhaust carbon build up soon. At the moment car is running a very rich mixture due to a malfunctioning VVT Valve. 6800 bucks from toyota to replace it!

What are the simptoms of a malfunctioned VVT-i valve. pls let us know. My car is also running bit of a rich mixture.

Edited July 27, 2009 by Corolla121

[virensti]

What are the simptoms of a malfunctioned VVT-i valve. pls let us know. My car is also running bit of a rich mixture.

well about 4 weeks ago my car was diagnosed to have a stuck vvt-i unit. (the unit thats on the cam shaft ifself under the tappet cover) so i was told this happens due to sludge formation. but to my luck the engine was spotless. Not a drop of sludge anywhere. So we assumed that when the car was in sing, they would've cleaned the engine out.(and the idiots there hadn't set it back up properly! the timing was all wrong! luckily wrong in a way where the engine could still run!) But they had over looked the vvt unit cause that was completely dry (it operates on oil [pressure) and there was no pressure getting through it which meant it was stuck. so on removal and inspection of it we found sludge. so with thinner under highpressure we cleaned out everything and when we started the car it was much smoother than what it was. (btw i should say that if you have a stuck vvt unit, the best way to check is to rev the car up to about 5000 RPM and smell the exhaust fumes. if you get a sulphur smell or a smell like a burnt fired cracker) its very possible that the vvt unit is stuck. so once we cleaned that after about 20 km's the CEL came on. so we reset the ECU from a scanner,and again after another 20 km's or so the light came back on. So i showed it to our normal garage (on the palawatta battaramulla road) and to some guys from "Arabian motors" and they both said to replace the vvt valve, which is NOT the vvt unit. It's what operates the vvt unit. You can find this valve in all vvt-i engines, ask any good mechanic to show you where it is, you can see it from the top of the engine without removing anything. The effects of this valve not functioning properly (As i was told) is, poor fuel efficiancy, slightly rougher idle and a smell of petrol from the exhaust which means rich mixture. and although i cant tell much about the idle, the car sure is doing poorer on fuel and there deffinitly is a smell of petrol from the exhaust.

whoa. i said alot.. sorry about that Corolla121 and others for going quite OT. but i just wanted to say the whole story rather than parts. So yeah Corolla121 my symptons of the malfunctioning VVT VALVE is the CEL coming on and a smell of petrol from the exhaust which means rich mixture in the cylinders... Oh and the error code i think is P1349 VVT-i malfunction, bank 1.

[GihanFX]

Please keep updating as and when there are more findings. I'm really keen to find out how many of us are seeing a difference...if this gets enough traction, maybe worthwhile a sticky...

today had a long chat with jehan @ senok abt this issue and he said so many people complain abt this issue and it seems no different between 90 and 95, but still cant come to a conclusion, well see

[Kim]

today had a long chat with jehan @ senok abt this issue and he said so many people complain abt this issue and it seems no different between 90 and 95, but still cant come to a conclusion, well see

U knw that i wouldnt switch back without a gud proper reason..trust me! pump 90OCT closing your eyes next time! and sit in thinking u pumped 95OCT and have a drive..u'll know then

[Corolla121]

well about 4 weeks ago my car was diagnosed to have a stuck vvt-i unit. (the unit thats on the cam shaft ifself under the tappet cover) so i was told this happens due to sludge formation. but to my luck the engine was spotless. Not a drop of sludge anywhere. So we assumed that when the car was in sing, they would've cleaned the engine out.(and the idiots there hadn't set it back up properly! the timing was all wrong! luckily wrong in a way where the engine could still run!) But they had over looked the vvt unit cause that was completely dry (it operates on oil [pressure) and there was no pressure getting through it which meant it was stuck. so on removal and inspection of it we found sludge. so with thinner under highpressure we cleaned out everything and when we started the car it was much smoother than what it was. (btw i should say that if you have a stuck vvt unit, the best way to check is to rev the car up to about 5000 RPM and smell the exhaust fumes. if you get a sulphur smell or a smell like a burnt fired cracker) its very possible that the vvt unit is stuck. so once we cleaned that after about 20 km's the CEL came on. so we reset the ECU from a scanner,and again after another 20 km's or so the light came back on. So i showed it to our normal garage (on the palawatta battaramulla road) and to some guys from "Arabian motors" and they both said to replace the vvt valve, which is NOT the vvt unit. It's what operates the vvt unit. You can find this valve in all vvt-i engines, ask any good mechanic to show you where it is, you can see it from the top of the engine without removing anything. The effects of this valve not functioning properly (As i was told) is, poor fuel efficiancy, slightly rougher idle and a smell of petrol from the exhaust which means rich mixture. and although i cant tell much about the idle, the car sure is doing poorer on fuel and there deffinitly is a smell of petrol from the exhaust.

whoa. i said alot.. sorry about that Corolla121 and others for going quite OT. but i just wanted to say the whole story rather than parts. So yeah Corolla121 my symptons of the malfunctioning VVT VALVE is the CEL coming on and a smell of petrol from the exhaust which means rich mixture in the cylinders... Oh and the error code i think is P1349 VVT-i malfunction, bank 1.

Hi virensti

Thanks for your long reply. its very informative. Mine also has a smell of petrol from exhaust and a rich mixture (plugs get brown after couple of days of cleaning). But no CEL on. funny thing is corolla 121 ECU cannot be modified. It’s a fixed thing. so no change of air-fuel ratio. any advice from the viewers. ?

Edited July 28, 2009 by Corolla121

[virensti]

Hi virensti

Thanks for your long reply. its very informative. Mine also has a smell of petrol from exhaust and a rich mixture (plugs get brown after couple of days of cleaning). But no CEL on. funny thing is corolla 121 ECU cannot be modified. It’s a fixed thing. so no change of air-fuel ratio. any advice from the viewers. ?

No worries man. I just hope i didn't bug the others of this topic by it cause it really was quite OT. I'm sorry again.

Corolla121 did you check for the sulphur smell from the exhaust? And I dont think any standard car ECU's can be modified as such. they can just be reset? I dont think anything else can be done to them. Unless you replace them with peformance ECU's or something.. (which I would LOVE to do )

Back onto 95 OCT petrol, i rubbed my finger in side the exhaust and got a bit of blackish soot like substance on my finger. (Which is obviously Carbon) but if 95 oct is causing this.. I heard that 95 is acutally 93 here in SL and 90 is about 89? so if that's the case our cars can't run properly right? cause i know for a fact the vios 1NZ-FE engine requires 91 OCT and above.. (That's what the owners manual says).. so won't it be a problem anyway we take it?

Edited July 28, 2009 by virensti

[CARBON]

today had a long chat with jehan @ senok abt this issue and he said so many people complain abt this issue and it seems no different between 90 and 95, but still cant come to a conclusion, well see

Someone should do a Gross Calorific Value test on both the 90 and 95 to see if there is a difference. Lab test may cost about Rs 25k. Big question is who will pay for this ?

Is is any other way to test the difference other than whats on the petrol pump ?

Now running with 95 ( I think if thats what they say they are puming) and octain booster. Octain booster also says will give a increase of 2 to 5 in the rating. This I feel is a big gap considering you are not sure by how much it will increase. So if we do the math

90 Oct pirce is Rs 130/=

95 Oct is Rs 148/=

So for 5 extra points we pay Rs 18/= extra. wurth Octain booster is Rs 1,250 and will treat 60 lts of petrol.

This gives us Rs 20.8 per ltr, So if we get the maximum ( ie 5 ) we still paying more than what Govt is charging ( This is ok for Barnd name , quality etc ). The real problem is if we get the lower which is only 2, then it just becomes a waste.

Again even if wurth cannot confirm the incremental octain level what assurance do we have than Ceylon Petrolium can confirm as exactly 95 ?.

[gunat]

All very valid points.

If there was an 'unofficial' way of confirming the same from the said distributors, then we'll be in a better situation to judge what is best for the cars we drive.

Here's a question for the ECU buffs: is there a way to plug into the ECU to find out what kind of fuel mapping a car is using?

What is definitely known is that the ECU uses a breadth of information (fuel, air, load) to determine the correct mapping for a car. I know most OBD readers can plug into the ECU and give errors...but i would think that an aftermarket ECU with more advanced software can give more information.

Anyone?

[STi B4]

All very valid points.

If there was an 'unofficial' way of confirming the same from the said distributors, then we'll be in a better situation to judge what is best for the cars we drive.

Here's a question for the ECU buffs: is there a way to plug into the ECU to find out what kind of fuel mapping a car is using?

What is definitely known is that the ECU uses a breadth of information (fuel, air, load) to determine the correct mapping for a car. I know most OBD readers can plug into the ECU and give errors...but i would think that an aftermarket ECU with more advanced software can give more information.

Anyone?

Will let you know about that in the coming month or so as a new toy is on the way for my baby.....

However according to Jehan, apparently car mart and some others have sent fuel samples to singapore to be analysed. So looks like we are not alone in this matter....