4.3 Pre cat - very strong fuel smell

[netdream]

Hi everyone and I hope you are all keeping safe in these difficult times.
One bonus is I have more time to get my Griff on the road.

I had a serious fuse box meltdown some years back and al slowly working through the electrics on the vehicle to try and get her up and running.

I live in France and TVR skills are pretty non existant as far as I know (if anyone is an expert and lives near Cannes I would love to hear from you)

I have got the car up and running but have a very strong smell of fuel when she is running. The car is in pieces so it has not had a drive for a while now.

In the absence of any specialists I am trying to work my way through the issues and have the bible and rover gauge as my guide.

I have no obvious fuel leaks.

I am working through tests on the ECU side of things - Temp sensors, MAF etc but before I waste a lot of time chasing red herrings I am hoping for some enlightenment.

1) When I start the car and it is at idle I hear a tapping noise - The car has recently been to a ' TVR specialist ' and they tell me the noise is probably sticking injectors.

2) I have intermittent fuel pump issues. On ignition the two brown bosch relays on the loom always click but I dont always have the fuel pump prime. I seem to be able to repeat the process of going between ignition off and to accessories and most times it primes but sometimes (possibly after she has started a few times) I have no priming. After she runs for a while one of the relays on the loom does become quite warm;

The fuel pump was replaced a few years back but maybe I have a problem with the pump itself as I have not driven the car and the pump maybe suffering from dirty fuel ?

While I have been rewiring the car I have been removing the tank when I know I wont be working on it for a while.

3) When the pump does operate and the car starts I always have a strong smell of fuel.

I have taken a log on rovergauge and hope that one of you way smarter petrol heads may be able to confirm if anything looks odd. but I am not sure if I can upload a file va PH other than images.

I see no errors in the diagnostics

Really appreciate any help

[netdream]

https://www.pistonheads.com/gassing/topic.asp?h=0&...

Found an excellent post relating to my fuel pump issues so I will refer to that for fuel pump investigation.
Thanks Steve and Blitzracing for all the great info in that posting

[blitzracing]

In terms of fuel smell check firstly for any fault codes. Check the AFM reading in direct mode, it should be about 35% on a 5ltr at tickover. Check the long and short term fuel trim. The long term should be less than about 70% (30 % or less is good). Short term should cycle around the mid point, adding and removing fuel.

[davep]

The OP's car is a 4.3 pre-cat, so no trim values.

Pre-cats on the original Green tune do have a tendency to overfuel at start-up.

This site has a lot of useful info on changing the tune to achieve better fuelling:

http://www.remap-14cux.uk/

Have you tried this locally based 'english car specialist' yet?:

https://www.tecm.fr/

When I was down in 06 ex-pats used them with varying levels of success, could be worth a try.

Edited by davep on Sunday 26th April 14:01

[netdream]

Hello and thank you for your responses.

Fuel Pump issue is now sorted. I had an intermittent ground issue.

Car now primes and starts every time I try it !!!!!

I have tried the garage you mentioned and they were who thought the ticking noise on idle was due to sticking injectors.

Is that likely ? - Could that also explain the fuel smell.


Below is a screenshot of rovergauge - It shows no fault codes.

On idle she sits around 1000 RPM and MAF reading is around 37 percent.

As part of my tests around the fuel pump I connected a fused battery connection directly to the pump - No smell of fuel so I would be reasonably confident that I have no leak.

Thanks again

Edited by netdream on Sunday 26th April 15:17

[davep]

Your Main Voltage is low. That will cause the injectors to open for longer, so more fuel. All the while the injector voltage supply is low (Main Voltage), the ECU will try to compensate by issuing longer pulse widths.

Look to your battery and alternator circuit, these cars need a battery that is in its best condition.

[netdream]

Thanks all.

Ok - Fully charged battery but still a strong smell of fuel from the exhausts. Occasional backfire as well.
Maybe she just needs a run ? but that is not possible for the time as I have no seats, dash is out etc.

I do think I had the fuel smell before the wiring meltdown but if I did, it seems to be much stronger now.