Over fueling or Injectors or Something else

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Jaco1981
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Over fueling or Injectors or Something else

Post by Jaco1981 »

Hi Guys

I recently bought a 200sx S13, this is my first Nissan and first turbo car.

There are a few minor mods to it, unfortunately I don't know what was done to it or how it was done and the previous owner bought it like it is now
Everything seems to be fine, I just have one problem, the car is overfueling. I know this because the exhaust gas smells of petrol and the oil in the motor smell of petrol. When the motor reach optimal working temp, it idles uneven, sometimes almost stalling.

I have been through this forum, some others and the google machine.

I have learned a few things but just cant seem to figure out some things, I really hope you guys can point me in the right direction.

What I know about the car.
The motor is stock
There is a different / bigger turbo. It runs 0.8 boost, is that stock?
Front Mount intercooler
There is a piggyback chip fitted by Dynoteck
There is a bigger exhaust fitted

Things that cause overfueling (according to what I think I have learned)

1. ECU / chip / Mapping
2. Airflow meter
3. Injectors
4. Boost leaks
5. Coils
6. Fuel pressure
7. Coolant temp sensor
8. Ignition timing
ps, the above list is not in any particular order :wink:

What I have done up to now

1. ECU/Chip/Mapping. I have made a booking for the car to go to Dynotech so that they can have a look at the chip and map to see if that is the problem. Its only going in on the 22nd :evil:
2. Airflow meter. I replaced the cone filter with a new one, I clean the AFM with cleaner
3. Injectors, I haven't touch that yet, I did notice that there are fuel on the manifold, so they will have to come out at some point.
4. Boost leaks, did not touch that yet
5. Coils, did not touch that yet
6. Fuel Pressure, did not touch that yet, finding a gauge seems to be a mission
7. Coolant temp sensor, did not touch that yet
8. Ignition Timing, did not touch that yet

Below is a link to a video I made

https://youtu.be/NcoJxgnSG2o

There is a sensor in the exhaust system. Did these cars come out with this, or is this only for the after market gauge?

After I cleaned the AFM the gauge went to lean and later to optimal. I drove home from work, and when I left again it went all the way to rich again. Drove about 20km and could allready smell the petrol in the oil (I did an oil change when I cleaned th AFM)

The one heater pipe was leaking, I replaced that today, and when I started it up afterwards to test for leaks, the air fuel ratio gauge stayed on lean and the eaxhust gas didnt smell of gas :? I waited till it was at optimal temp and it idle fine

I am super confused now.

Any thoughts would be greatly appreciated!!!

Please note, I am no mechanic, but love to fiddle, so please dont get to technical and pics is always awesome!!! :D [smilie=200sx_200sx.gif]
Last edited by Jaco1981 on Wed Oct 28, 2015 9:48 am, edited 5 times in total.
Ex: 1985 Alfa GTV 2.0
Ex: 1981 Alfa GTV 2.0
Ex: 1989 Honda Ballade 160i DOHC
Ex: 1991 Honda CRX
Ex: 1997 Honda RVF 400
Ex: 2007 Yamaha R6
Current: 1991 Nissan 200sx

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troopiec
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Re: Over fueling

Post by troopiec »

Hey dude don't have time to give a full explanation of possibilities but another component which influences fueling is then Ecu coolant temp sensor, it is a 2 pin sensor which sits above the thermostat, also influences fueling according to coolant temp and when faulty can cause a few fueling issues, but dynotec should be able to figure it out quite quickly. Very likely just need some tuning and adjustment

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Jaco1981
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Real Name: Jaco
Location: Cape town, South Africa

Re: Over fueling

Post by Jaco1981 »

troopiec wrote:Hey dude don't have time to give a full explanation of possibilities but another component which influences fueling is then Ecu coolant temp sensor, it is a 2 pin sensor which sits above the thermostat, also influences fueling according to coolant temp and when faulty can cause a few fueling issues, but dynotec should be able to figure it out quite quickly. Very likely just need some tuning and adjustment

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I forgot about the coolant temp sensor as a possibility. Thank you

Will edit my post to ad it to the list :)
Ex: 1985 Alfa GTV 2.0
Ex: 1981 Alfa GTV 2.0
Ex: 1989 Honda Ballade 160i DOHC
Ex: 1991 Honda CRX
Ex: 1997 Honda RVF 400
Ex: 2007 Yamaha R6
Current: 1991 Nissan 200sx

SonOfAnarchy ZA
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Re: Over fueling

Post by SonOfAnarchy ZA »

Chip is badly tuned or coolant temp sensor most likely the second option
"I'd rather lose by a mile because I built my own car, than win by an inch because someone else built it for me"

Jaco1981
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Real Name: Jaco
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Re: Over fueling

Post by Jaco1981 »

Ok, so my car went to Dynotech today.

Car makes 147kw @ 6000rpm & 252nm @ 5400rpm

They said there was nothing to change on the chip and that the air fuel ratio is fine.
So I think its time to look at the injectors, maybe dripping?? Any thoughts?

btw, where can I buy gaskets/seals/insulators for my injectors?

Thanks
Ex: 1985 Alfa GTV 2.0
Ex: 1981 Alfa GTV 2.0
Ex: 1989 Honda Ballade 160i DOHC
Ex: 1991 Honda CRX
Ex: 1997 Honda RVF 400
Ex: 2007 Yamaha R6
Current: 1991 Nissan 200sx

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Draco
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Re: Over fueling

Post by Draco »

Jaco1981 wrote:Ok, so my car went to Dynotech today.

Car makes 147kw @ 6000rpm & 252nm @ 5400rpm

They said there was nothing to change on the chip and that the air fuel ratio is fine.
So I think its time to look at the injectors, maybe dripping?? Any thoughts?

btw, where can I buy gaskets/seals/insulators for my injectors?

Thanks
If the car was over fueling so bad, the AFR would show that, if there is fuel leaks you will see and smell it below the fuel rail, the running uneven when hot might be something to look at but I'd say over fueling is out, unless dynotech has no clue.

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Charlvdw
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Re: Over fueling

Post by Charlvdw »

I think that afr gauge of yours is just hooked up to a narrowband signal, maybe post a pic of the sensor.
If your oil smells of fuel your injectors are probably leaking and seals are not gonna fix that, have them flow tested.
197rwkw ,376nm

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Draco
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Re: Over fueling

Post by Draco »

I'd like to believe dynoteck used their afr equipment, therefore what his gauge says is irreverent.

Jaco1981
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Re: Over fueling

Post by Jaco1981 »

I suspected that the gauge was reading wrong, but that is not why I thought there was an overfueling problem. There is petrol in the oil. I am sure Dynotech know what they are doing, so yes, overfueling can be ruled out. I'm going with dripping injectors for now.
Ex: 1985 Alfa GTV 2.0
Ex: 1981 Alfa GTV 2.0
Ex: 1989 Honda Ballade 160i DOHC
Ex: 1991 Honda CRX
Ex: 1997 Honda RVF 400
Ex: 2007 Yamaha R6
Current: 1991 Nissan 200sx

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troopiec
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Joined: Mon Dec 26, 2011 11:00 pm
Car: S13

Re: Over fueling

Post by troopiec »

How rough is your idle that you speak of? Remember an sx and ca18 is not going to idle like a new car. Even mine has a bit of a lumpy idle but goes 100percent,

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Jaco1981
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Joined: Wed Oct 22, 2014 4:24 pm
Car: S13
Real Name: Jaco
Location: Cape town, South Africa

Re: Over fueling

Post by Jaco1981 »

troopiec wrote:How rough is your idle that you speak of? Remember an sx and ca18 is not going to idle like a new car. Even mine has a bit of a lumpy idle but goes 100percent,

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Sometimes it idle's perfect, sometimes it up and down by 300 or so rpm. The motor stalled once or twice, but most of the time its ok :!: :?: :idea:
Ex: 1985 Alfa GTV 2.0
Ex: 1981 Alfa GTV 2.0
Ex: 1989 Honda Ballade 160i DOHC
Ex: 1991 Honda CRX
Ex: 1997 Honda RVF 400
Ex: 2007 Yamaha R6
Current: 1991 Nissan 200sx

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Enzio
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Re: Over fueling

Post by Enzio »

troopiec wrote:How rough is your idle that you speak of? Remember an sx and ca18 is not going to idle like a new car. Even mine has a bit of a lumpy idle but goes 100percent,

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Then your car is not right. A CA idles perfectly smooth if it is mechanically sound.

Jaco,

If you have fuel in your oil, stop driving it immediately before you destroy your engine.
You have previously mentioned you have leaking injectors and that there is fuel on the manifold - you do realise that that is a MAJOR fire hazard??

Charl has already given you good advise - take your injectors out and have them flow tested and cleaned. Then replace all of the O-rings in insulators. They will replace the injector caps as well, which would have already cracked and broken apart now due to age.

It boggles the mind why you would spend money to "tune" away a mechanical problem which you have already identified.

Crap idle - common causes in no particular order:
- faulty coil pack
- faulty wiring (check grounds)
- spark plugs: too large gap or fouled plug or faulty plug
- poor compression: rings, valves, stuck lifter
- fuel issue: as per above which you need to fix in any case.
- vacuum leak
- dirty MAF
- Timing: mechanical (wrong alignment on cam sprockets) and base timing incorrect.
Image S13 CA18DET, NIStune and...oh wait no that's gone..... Image

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troopiec
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Re: Over fueling

Post by troopiec »

300rpm too much, my motor will maybe jump 50rpm here and there at idle. It's an old motor not a reconditioned engine. Injectors are probably not 100percent equally fueling etc, but every ca I've driven has been like that, one day when I overhaul everything itl be right but at the moment the car has been driving strong for 4 years so not gonna scratch where it does not itch. But yea yours sounds a bit much

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Jaco1981
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Car: S13
Real Name: Jaco
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Re: Over fueling

Post by Jaco1981 »

Enzio wrote:If you have fuel in your oil, stop driving it immediately before you destroy your engine.
It's not my daily, it's standing locked up :wink:
Enzio wrote:You have previously mentioned you have leaking injectors and that there is fuel on the manifold - you do realise that that is a MAJOR fire hazard??
Yes, I do realize it is a hazard, one of the reasons why I don't drive it at the moment
Enzio wrote:Charl has already given you good advise - take your injectors out and have them flow tested and cleaned. Then replace all of the O-rings in insulators. They will replace the injector caps as well, which would have already cracked and broken apart now due to age.
Yes, that is the following step. I don't have a lot of free time, so the car is parked till I get round to it
Enzio wrote:It boggles the mind why you would spend money to "tune" away a mechanical problem which you have already identified.
Because, until yesterday I thought it was a badly tuned chip.

Thank you for the list of reasons for bad idle. As soon as I have the injector / fueling sorted, that will be the next thing I'm looking into :wink:
Ex: 1985 Alfa GTV 2.0
Ex: 1981 Alfa GTV 2.0
Ex: 1989 Honda Ballade 160i DOHC
Ex: 1991 Honda CRX
Ex: 1997 Honda RVF 400
Ex: 2007 Yamaha R6
Current: 1991 Nissan 200sx

Jaco1981
Slipping Clutch
Posts: 29
Joined: Wed Oct 22, 2014 4:24 pm
Car: S13
Real Name: Jaco
Location: Cape town, South Africa

Re: Over fueling or Injectors or Something else

Post by Jaco1981 »

Ok, so I took out the injectors last night. On the side it have the following numbers: A46-00. As far as can can figure out, the CA18DET comes stock with 370cc injectors and that A46-00 is stock 370cc injectors. Can anyone confirm if this is right?

A few of the rubbers are damaged. The electrical connectors, half of them were already broken and the other half broke last night as I took them of. Is the connectors a general type connector or is this something that have to be bought at the agents?

Below are some pic's

Image
Image
Image
Ex: 1985 Alfa GTV 2.0
Ex: 1981 Alfa GTV 2.0
Ex: 1989 Honda Ballade 160i DOHC
Ex: 1991 Honda CRX
Ex: 1997 Honda RVF 400
Ex: 2007 Yamaha R6
Current: 1991 Nissan 200sx

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