Over Fuelling

[PumaJay]

This is something that has plagued my puma for a little while but seems to be getting worse.

Now I do know the my exhaust is blowing at the flexi pipe which obviously isnt going to help matters but when driving around the smell of fuel is quite over powering, ive also been told it can be smelled when following the car around.

The mods I have on the engine side of things is.
Piper 421 mani and full s/s system with de cat
FRP map
Induction kit
ported MAF and TB

now I know the FRP map is designed to work with a higher air flow than what the standard engine provides but surely it shouldnt make it as bad as it is.

When I was out on track at the weekend the smell inside the car go so bad I could only managed 10 mins in the car!

Any suggestions? Im sure getting it sorted wont be too difficult and getting it running right is my No1 priority right now.

 

[fiestaseb]

Sounds silly, but fuel leak? Fuel lines re routed into the car? Dodgy O2 sensor?

 

[PumaJay]

I think the O2 sensor is ok... I'm going to get underneath the car this weekend and have a good check over a few things. Fuel lines are all in OE position I've not touched them.

Got an oil leak to fix as well! Never ends!

 

[DOH]

In addition to checking for fuel leaks ,the lambda and wiring (a fault will show up with an OBD Tester), also check the fuel pressure regulator on the injector rail, the diapragm may be torn or it may just be sticking. However usually a sign its faulty is that the plugs will soot up at idle with a lumpy tickover, have you those additional symptoms also?

 

[PumaJay]

Im going to have a good strip down and look at everything this weekend.

I'l probably replace the plugs anyway, check the lamdba sensor and wiring to it. Will be booking the car in for a new s/s centre section in the exhaust to repair the blowing flexi pipe.

Also thinking of running a sytec adjustable fuel pressure regulator with wide band so I can fine tune it a bit better.

And if anyone has some FRP spec cams then im after some!!

 

[PumaJay]

Im going to have a good strip down and look at everything this weekend.

I'l probably replace the plugs anyway, check the lamdba sensor and wiring to it. Will be booking the car in for a new s/s centre section in the exhaust to repair the blowing flexi pipe.

Also thinking of running a sytec adjustable fuel pressure regulator with wide band so I can fine tune it a bit better.

And if anyone has some FRP spec cams then im after some!!

 

[trublustu]

The blowing exhaust wont be helping. You will be using more fuel. All cars do..
But not so much that you can smell it...

With the petrol smell, it sounds like a leak.
Wait for a dry spell then jack the car up safely, start the engine and look for signs.
If its the filler neck (not unheard of) it wouldn`t show unless tanked to the filler or taken for a spirited drive first. :wink:

 

[PumaJay]

Yeah the exhaust is one of the first things im going to get sorted, will hopefully be taking it to MIJ exhaust for a new centre section in the next couple of weeks.

I dont think its a leak as such, the last time I had it on a rolling road the guy told me it was over fuelling so.... I am going to check for leaks, will get it up nice and high on some axle stands and have a look look underneath.

It might something as simple as the wiring to my lambda sensor has melted, I had to extend it when I fitted my 4 branch a few years ago.

 

[Ziggy]

To have that strong a smell of fuel would mean massive overfuelling not just a bit caused by a modified MAF / throttle going out of calibration. Upping the fuel pressure will make the ECU shorten injector times based on readings from HEGO sensor. The ECU will either get it back within limits or throw an error code.

If the HEGO has neat fuel going over it it will most likely need replacing.

I'd check for fuel leaks first, might be a hole in the tank which when cornering allows fuel to leak out. Might also be worth getting someone to follow you to see if they can spot the fuel leak.

 

[PumaJay]

^^^^ Have tried that and havent had any reports of it being a leak, the car is often stood for weeks at at time down the side of my house and there has never been a fuel patch anywhere under the car.

 

[grayfox]

I dont think its a leak as such, the last time I had it on a rolling road the guy told me it was over fuelling so.... I am going to check for leaks, will get it up nice and high on some axle stands and have a look look underneath.

Don't mean to state the obvious but it will be overfuelling if your running an FRP map without the equivalent cams (unless you didn't have the map installed at this point)

 

[PumaJay]

I did it way before I had the map put onto the ECU.

 

[grayfox]

I did it way before I had the map put onto the ECU.

 

[madhillbilly17]

i would go for the fuel pressure regulator or 02 sensor,if it's over fueling that bad your mite want to change your oil,mine was over fueling and my oil was contaminated.

 

[trublustu]

I just ran at Oulton Park with the FRP map but cams not fitted.

No fuel smell in the slightest.

I actually happy to report better than usual fuel consumption
(13.8 instead of 12 mpg)
Everyone in my group did.
Conditions were chilly and a little damp.
We put it down to that. (sorry to drift off the point)

 

[PumaJay]

i would go for the fuel pressure regulator or 02 sensor,if it's over fueling that bad your mite want to change your oil,mine was over fueling and my oil was contaminated.

Thats going to be my first port of call.

Do the FRP's run a different fuel pressure regulator or are they all the same?

Ive got a nice 4 day weekend coming up this week so Monday will be spent working on the car trying to sort a few issues.

First off, fix the oil leak, then service, new exhaust centre section, check 02 sensor wiring.

 

[DOH]

The FRP Fuel pressure regulator is a different part number to the standard 1.7. It therefore runs at a different pressure.
Cam timing can also put the fueling out significantly.
Professional engine builders in the past have always clocked the cams in on the full lift position for each cam. Obviously check with piper for the exact value for the FRP cams, but many engines are in the 104-106 Degrees BTDC & ATDC range.

 

[Wild E. Coyote]

The FRP Fuel pressure regulator is a different part number to the standard 1.7. It therefore runs at a different pressure.
Cam timing can also put the fueling out significantly.
Professional engine builders in the past have always clocked the cams in on the full lift position for each cam. Obviously check with piper for the exact value for the FRP cams, but many engines are in the 104-106 Degrees BTDC & ATDC range.

Would you happen to know the part number of FRP fuel pressure regulator and where can it be obtained from?

Ta in advance,

 

[DOH]

There is mention of the part number and a photo if you use the search facility. however it would be better to buy an adjustable fuel pressure regulator and set the pressure to the pressure used for the FRP map. I would recommend purchasing from the UK wholesale suppliers and speak to Terry at http://www.glencoeltd.co.uk/

 

[PumaJay]

That website is awesome!!

I was going to get mine off eBay but it's much cheaper from there.