Multiple problems! Smoke and massive fuel usage

[Fishfire]

Hi all, my first post as I've been unable to find anything here which answers the problems I'm having.

I've acquired an '03 172 that is in need of a little bit of love but has generally been running ok until yesterday.

The engine management light has been flashing on and off for a week but is now on constantly.
The car is very hesitant from standstill but gets better with revs.
Now she's smoking like a challenger tank on exercise and using a ridiculous amount of fuel ( 1/4 tank in 11 miles!!) And flumes of white smoke that smells heavily of unburnt fuel.

I've used my scan tool to find the fault codes and it's held the following codes:
• Multiple misfires
• O2 sensor heater circuit malfunction (bank 1 sensor 2)
• Vehicle speed sensor A malfunction

I've had the plugs out and no.3 and 4 plugs are badly fouled with black carbon.
I've replaced HT leads as I bought a few service items, and have plugs on order.

Apart fron the smoke and fuel disappearing at a rate of knots, the car seems to run ok though it's very lumpy at idle. From what I've read this seems normal?
There's no oil in the coolant and oil isn't emulsified.
I've pulled various HT leads off the coil pack and oddly it seems to run exactly the same on any three remaining leads.
With the overfueling i thought perhaps an injector or injectors are stick open?

Any thoughts, advice or fixes would be gratefully received!

 

[bloke]

injector and chances are lambda.

 

[STEVE.M]

You could swap the lambda`s as they are both the same to see if the lambda fault moves to the precat position.

Do a set of both dry & wet compression tests while the plugs are out.

As it`s a Renault, number 1 cylinder is at the gearbox end when it comes to interpreting diagnostic codes.

Probably a faulty injector, but again, swap them round to prove the point.

 

[Coops Mk1]

as above, injectors for sure, they're very common for going on these engines

the o2 sensor faults are probably a result of the bad exhaust from the crapped out injectors so change them first imo

 

[Fishfire]

Thanks for all the replies chaps.
I've now got a coil pack, injectors and plugs on order!
Are the fuel pressure regulators reliable?

Just the cam/dephaser to organise now :/

 

[STEVE.M]

as above, injectors for sure, they're very common for going on these engines

the o2 sensor faults are probably a result of the bad exhaust from the crapped out injectors so change them first imo

Hope you don`t mind if I clarify you meant change the injector(s) before replacing the lambda.

 

[Fishfire]

I've not yet ordered any o2 sensors....I may see if it's possible to clean them up first.
All the bits shoukd be here by Tuesday (ish) so I'll be busy changing bits out next week.

Hopefully that little lot should solve a few issues.

The input is much appreciated

 

[STEVE.M]

[QUOTE="Fishfire, post: 11527946, member: 119595"

Are the fuel pressure regulators reliable?

Just the cam/dephaser to organise now :/[/QUOTE]

There is no pressure regulator on the fuel rail.

Where are you located, as belts/dephaser is bit of a specialist job.

See NT3286A for details in attached file.

 

[Fishfire]

Ah thanks for the file! Much appreciated :smile:

Tbh I'm going to do the belts myself. I've got an engine hoist, garage and most tools.
I'e always done my own work if I can and had some awkward cars to own/work on in the past including a mk1 Focus RS, Renault 5 GTT and a phase 1 Impreza....all arse to work on!

And I only paid £700 for the car so I can't justify the price of the car on work I can do myself tbh

 

[Fishfire]

I'm in Southampton btw

 

[Stay Puft]

I'm in Southampton btw

Bad luck!

Good specialist in Portsmouth if you do get stuck.

 

[STEVE.M]

Ah thanks for the file! Much appreciated :smile:

Tbh I'm going to do the belts myself. I've got an engine hoist, garage and most tools.
I'e always done my own work if I can and had some awkward cars to own/work on in the past including a mk1 Focus RS, Renault 5 GTT and a phase 1 Impreza....all arse to work on!

And I only paid £700 for the car so I can't justify the price of the car on work I can do myself tbh

If you are going to go for dephaser, auxillary & cam belt kits, water pump & coolant, most RS specialists charge £700, of which £160 is the labour content.
This is the price of the Renault timing tools you will need to carry out the work.

You will have a warranty on the work and parts, and you can probably earn £160 doing extra hours at your daytime job rather than grazing your knuckles.

Please note there are no timing marks or splines, & the pulleys are floating.

Good luck though if you attempt it yourself.

 

[Coops Mk1]

Cheers @STEVE.M my poor punctuation there! Yes look at injectors first

 

[Fishfire]

Defo not injectors!
Fitted today:
New injectors
New spark plugs
New HT leads
New coil pack

Cleaned the sensor attached at the top of the gearbox while I was there.
Upshot is, it idles soooo much better but still huge plumes of smoke out the exhaust.

No usage of oil or coolant that I can see.

Tbh I just want to fix her up enough to sell it on as I've just bought a very nice Monaco blue 172

 

[STEVE.M]

Tbh I just want to fix her up enough to sell it on as I've just bought a very nice Monaco blue 172 :wink:

Did you do a compression test while the plugs were out?
Also have you checked the level on the oil dip stick?

 

[bloke]

injector and chances are lambda.

 

[Fishfire]

Brand New standard injectors were fitted.
O2 sensors have been removed, cleaned up and replaced.
All fault codes have been wiped and so far it's not throwing up any more fault codes since replacing/cleaning important parts.

Idle is now near on perfect since replacing the plugs, leads and coil pack and cleaning the TDC sensor on the gearbox.

There is initial hesitation when you give it a few revs but power doesn't seem affected.

I'd be tempted to say it's head gasket or possibly valve stem seal, but tbh my interest level since buying my Monaco blue 172 has dropped off, and I think I'm going to cut my losses and sell it on as is, as a project/spares or repares, before I get too financially involved with it.