Help! Any tips to revive old Lupo?

[JedB]

Hi guys.

I have a 2001 Lupo 1.0 (70,000mi) thats was in the family for 7 years and well taken care of. Most recently had a new pedal box welded up and painted and reinstalled with a new clutch.

Sadly my sister had been unable to drive the vehicle for 3+ years and it had been sat with some intermittent starting to begin with but at least 1+ year of no starting and 3+ years not driven.

We did notice on a service a few years before she obtained it that the spark plugs were very carbony all black at the ends but replaced them (less than 1 year before it was left sitting) im not sure if this could be related but doubt it as car was running fine until it was left sat and may be something else we need to investigate once it gets running.

We have changed the oil and filter and air filter, we have changed the plugs and charged the battery with trickle charger. All the electrics are back to life and working now but the vehicle is cranking but not starting!

Does anyone have any other suggestions of what we could try? Someone suggested changing the fuel filter which I will do tomorrow but they said may need to do the pump too.

Any suggestions are really greatly appreciated!

[mk2]

Classic stored car syndrome. But not a problem. @Rich @lupogtiboy @ObjectiveAway  @tigcraft @Adam Meader @amgeriz what do you think?

You know when you burn petrol you get CO2 and water vapour resulting from the combustion process, if the engine was started regularly but not driven, the trapped condensation (water vapour) coats everything inside the engine when it cools down again. And the inside of the engine being steel (cylinder liners), they start to rust. As do the valves and the piston rings. And the exhaust system.

So the piston rings get stuck, the valves don't give a perfect seal and the rough corroded surface of the cylinders also prevents a good seal. So when you try starting the thing, you get no compression and as a consequence no firing up. Changing all the components/filters/oils won't make any difference (I'm assuming you have a good fresh fuel supply and ignition sparks in the plugs).

What usually works is to pull all the plugs out and put about a teaspoon or so of clean engine oil into each hole. Then spray a five second squirt of WD40 mist or similar in there to try and create a temporary seal on the valves. Leave the plugs out and crank away for 20 seconds every five minutes over an hour. You're trying to coat all the internals with oil and free up the stuck rings. Keep the battery on charge and don't burn out the starter motor.

Then replace the plugs, cross your fingers and try starting it again. Garage door open as there'll be LOTs of smoke and noise. Crank with wide open throttle (if your engine is manual cable throttle) to try and get max compression. If it starts firing, keep cranking with your foot on the throttle until it runs by itself, but do NOT rev it above 1500. As you could permanently wreck the engine. You're trying to get the internal surfaces to make friends again. Hold it at 1500 until the engine fully warms up.

Don't just switch off when done. When it's nice and hot, rev it up to about 3000 and hold it there- then switch off and then take your foot off the throttle with the engine still spinning fast. The idea is to keep the engine spinning, with no fuel or ignition to get the bores and lower pistons rings fully coated with oil. Allow to fully cool down, then see if it starts first time. If not, you'll have to do it all again and then take it for a good motorway run for about half an hour. 

You may also want to change the belts, change the brake fluid and flush the gearbox 👍🏻 And wipers. And coolant.

End of essay. let us know how you go.

[tigcraft]

@mk2 nicely worded!! What I would do to add to that is air intake pipe off and ‘chuck a grenade in it’ with some easy start, or squirt some ‘premium’ high octane petrol down the plugs then start it. Although OP says all the electrics are back and working, does that include spark plugs too? 

[mk2]

Yeah, good idea. Some easy start would be worth a try if after first try there's nothing...

[amgeriz]

Hi everyone!
I would check for fuel and spark. With key contact you need to hear the fuel pump relay on the fuse area and the pump from behind, and when it achieve work pressure they must stop, if not, there is no fuel pressure in the injection ramp. If it's fine take one old spark plug, and try to plug all four leads on it one by one, while the steel body is touching the engine, and crank it searching for spark. If there is no spark I would try a new crank sensor. That's a good start. If everything is fine i would continue trying all four injectors mounted on the ramp but out of the engine. Next I would try to borrow or buy a vagcom cable and software.
Cheers!

[Rich]

Since it's a crappy non starting one litre I would do as I always do and start by sucking the vacuum pipes and checking the one way valves etc are working. 

I hate auc engines. 

[ObjectiveAway]

On 1/9/2025 at 6:19 PM, JedB said:

All the electrics are back to life and working

Do You have spark?

This engine is really simple, remove the air filter and you will have easy access to everything. You should be able to start it and it should make some misfires.

I agree @Rich, its not the best engine at all, more over @JedBhave Euro 4 version, which needs two catalytic converters and working second O2 sensor to make it working properly.