Technical Smell of petrol

[Keepthe12alive]

Hello friends!
Hope you are well and having a wonderful start to the week!

I have been noticing a petrol smell about my 2011 1.2 Petrol Panda, and this is where I intend to chronicle my hunt for the problem!

I have already completed a head gasket repair with more than abundant help and guidance from members on this forum, and hopefully this can be of use!

Every kindness,
Peer Panda-maniac!
————

Wisdom going in: “Many things can be true. Start, however, with the simple things.”

Car symptoms:
- smell of petrol from exhaust
- smell of petrol when windows open and going 50mph
- smell of petrol at idle
- No trouble codes on dash

Other symptoms:
- occasional “shivery” idle at times
- Car shivers when I turn the headlights on and off at idle (could be charging system related)
- seems like it’s a big umph’ for it to start sometimes (feels rough, not smooth)

Hunches going into the project:
- Petrol in exhaust likely means sub-optimal fuel/air ratio during combustion, and could also result in rough idle
- I did have to cut and refit the fuel line to the fuel rail when I was struggling to disconnect it while removing the intake manifold, so potentially there is a problem there.

Initial plan:
1. Hook my scan tool up and see if anything pops up
2. Look at the engine while running to see if I notice any leaks (looking along fuel rail, etc.)
3. Purchase a fuel system due to try identifying any leaks with my UV light
4. See if I smell petrol near the gas cap — could be simple fix

 

[Keepthe12alive]

Well, I’ve done the following:
- smelled around gas cap, can’t really detect petrol
- exhaust I think still smells of petrol?
- I did notice that when I unscrewed the protector cap on the release valve on the fuel rail, it sounded like pressure released and the cap was wet with petrol and it looked like there was petrol inside the vale area
- couldn’t see much happening by the injectors, though vision is limited because the air filter assembly is right overtop it
- the place were I reconnected the fuel line to the fuel/injector rail seems fine — couldn’t find or smell any petrol around it
- no codes on scanner, and attached are various load readings, etc.

 

[Keepthe12alive]

Additionally, I am considering getting a UV fuel dye.

This is the one that seems the most legit — anyone have thoughts?

https://www.amazon.co.uk/Torch-Detection-Fluid-Petrol-Diesel/dp/B00TU9BHN6

 

[koalar]

The evap system can cause fumes

Daft question, the blue pipe on the passenger side of the inlet manifold has been connected back up, the car will run fine with it disconnected

If you lift the rear seat up, you should be able to tell if the smell is from the front or back fairly quickly

Cars without split rear seats are very easy to lift up

 

[Keepthe12alive]

Do you mean disconnect this?

 

[koalar]

Yep that's the one

The blue pipe looks fine in the photo

Is the electrical connector fully plugged in

Looks slightly ajar

 

[Keepthe12alive]

It’s physically clipped in as much as possible

Idk if the connector itself got weirdly situated or something

 

[Keepthe12alive]

as for the seats, didn’t realized I’d have to empty the trunk (where all my marketplace tool finds are and my mobile panda-repair shop for this car lol), so that’s a job for, well, not 9:00pm lol

 

[Keepthe12alive]

Yep that's the one

The blue pipe looks fine in the photo

Is the electrical connector fully plugged in

View attachment 452197


Looks slightly ajar

Btw, would you happen to know if using that dye is okay for this fuel system?

(Not getting it just yet, just want to save it to my tool list if it works)

 

[koalar]

Assuming the scanner is reading right

Stft are maxed out
LTFT are maxed out


What's the inlet pressure engine off
What's the inlet pressure at idle

 

[Keepthe12alive]

What would those be abbreviated as?

 

[koalar]

Btw, would you happen to know if using that dye is okay for this fuel system?

(Not getting it just yet, just want to save it to my tool list if it works)

Never used it

So no idea

Had fuel leaks, there usually fairly obvious

 

[koalar]

What would those be abbreviated as?

Sorry

STFT and LTFT are the standard abbreviation for

Short term fuel trims
Long term fuel trims

On your scanner

Shrtft1 looks like it means

short term fuel trims bank 1

Normally the trims are around 0 give or take a bit

But If one is at 50 and the other is minus 50 it's still around 0

But you have both maxed out in the positive, either the scanners wrong, you have too little fuel pressure, too much air going in, O2 sensor reading wrong, or something I have missed

If it's a large air leak we should be able to see by just by reading the inlet pressure via the scanner it should read 1000 at engine off and 300 at idle

 

[Keepthe12alive]

Sorry

STFT and LTFT are the standard abbreviation for

Short term fuel trims
Long term fuel trims

On your scanner

Shrtft1 looks like it means

short term fuel trims bank 1

Normally the trims are around 0 give or take a bit

But If one is at 50 and the other is minus 50 it's still around 0

But you have both maxed out in the positive, either the scanners wrong, you have too little fuel pressure, too much air going in, O2 sensor reading wrong, or something I have missed

If it's a large air leak we should be able to see by just by reading the inlet pressure via the scanner it should read 1000 at engine off and 300 at idle

I only just realised the scanner is meant for American cars, so it’s not EOBD

I may have to have my mechanic hook up too it