Technical Fiat Punto Evo CNG/Biogas

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Technical Fiat Punto Evo CNG/Biogas

Jukkah

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Greetings from Finland!

I'm new to the forum and quite honestly new to owning Fiat. I recently bought a Fiat Punto Evo with a, how shall we say... questionable past.

The car is a factory-made CNG Natural Power setup, which was initially the reason I decided to get it as our city recently got the first biogas station.
It's a 2012 model, 5-door, dark metallic grey. With the 1.4 8V 77hp engine. 118 000 km on the meter. It has both a 15kg CNG tank and a full petrol tank (45l), so it has a pretty nice range.

The questionable past involves being owned by a Swedish community, then shipped to Finland where someone drove it for three years, apparently changed it at a dealership that then auctioned it. I bought the car from a guy who bought it from the auction and wasn't really honest about its faults. The most concerning thing is that according to the service manual the car has had maintenance only at 66 000 km, 82 000 km and 112 000 km. If those are indeed the only services, it's apparent that the engine has been run on the same oils way too long. I guess the only way to find the real damage would be to open the block and see how the bearings look like. The good thing is that the engine seems to be pulling nicely and sounds healthy, so I'm hoping someone at the Swedish community has been changing oils to her manually and not putting in the service book, but I know this might be wishful thinking.


Now here's the list of things that need fixing:

The other concerns are that there is black/brown residue at the top of the overflow chamber, not in the coolant. The coolant is bright and doesn't have any oil in it. Oil is very clear as well, but most concerningly there is too much of it. The engine also doesn't keep temperature up when driving on the freeway and the air from the heater isn't really hot. I only noticed this once I drove the car home and haven't actually ran her since. I'm really hoping it's just a case of a broken thermostat and overfilled oil, but I realize these could symptoms of a blown head gasket. But like I said, the fluids seem clear and if there was so much coolant at the bottom of the oil pan to raise the oil level, I'd presume it would show in the dipstick and valve cover as sludge. I've booked maintenance for Monday for a thermostat change, oil change, leak down test and wheel angle setup because the car also pulls slightly to the right. Most of these repairs I could handle myself, but I don't really have the facilities or the time currently and it's a hassle to get rid of the coolant and the oil after a change.

Other not so critical, but annoying things include:
- Cracked windshield (250€ at the shop)
- Rear bumper has a crack in it and a small dent in the bodywork above it (I can fix the bumper, but the dent probably needs some PDR work from a pro)
- Right side doors have dents and paint damage in them (PDR and probably touch up the paint myself)
- Rocker panels have lost all paint in the front from the debris flying out of the front wheels. They're basically sandblasted. Not good with our salty roads, no visible rust damage yet though. (Antirust primer, paint, mud flaps. Easy DIY job).
-Rear window mechanism was broken but the previous owner had bought the part and it was a easy fix I already managed to do.
-All sorts of little wore down things. The remote key looks horrible and doesn't stay closed, the rear hatch plastic panel is cracked, boot shelf is missing some parts and other minor annoyances.
-Lot's of little paint chips. Looks like Fiat has had some manufacturing issues with the paint.

So as you can see, a lot of work to be done. I'm not a mechanic but I'm an engineer that actually studied automotive engineering for a year before changing to environmental technology (so from petrol to biogas ;). The only engine work I've done is pulling apart the valve head of an OHC Opel engine and changing the gaskets and belt while at it. I'd presume the Fiat engine isn't much more difficult than this so I'm not really worried about a head gasket change. If the engine turns out to be completely gone, I will either strip it down myself and take to an engine shop for honing and bearing change or get a replacement engine and change it myself. I have no experience in either but I, fortunately, have friends that can help me out. Can't be that's much harder than changing a cylinder head.

Sorry for the long post and thanks for reading if you made it this far. My biggest motivation for writing this was to get some social support :). I guess you guys are the only ones that can understand buying a beat-up Fiat, lol!

P.s. I got the car very cheaply considering the age, but I still think I paid too much for it... I'm going to do my best to bring her back to life but I'm a bit apprehensive of her reliability as a daily driver. I'm also thinking about turning here into a hypermiler and convert the petrol system to bioethanol, so I'd have a range of about 1000 km on near-neutral CO2 fuels. I have no idea how this engine likes ethanol. I guess the only thing I can really change to reduce fuel consumption is the tires, so if you have any recommendations or tips I'd be glad to hear them.
 
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Welcome to the forum.

It definitely sounds like this car has had a hard life.

I wouldn’t be overly bothered about dents and scratches on an 8 year old car, I definitely wouldn’t spend any money on them till the rest of the car is sorted out.

Back when I owned my grande with the same 1.4 8v I had a problem with an airlock in the popes going to the heater, I struggled to clear it but eventually managed by feeding a hose pipe down into the heater and flushing it all out then in essence directly filling the heater core with water, after that it worked brilliantly.

It’s quite posssible from your description that the black/brown residue is from years of someone mixing coolants when topping it up, but more recently someone has changed the coolant and the result is an airlock, you also may have a Weak or faulty thermostat that’s not closing properly.
 
Thanks for the tips Andy! Yeah I wasn't planning on putting any more money into it until I have the engine sorted out and know if it needs some major work. I think the leak down test will show any major problems but won't of course show any bearing wear down. The car is going to the shop Monday so they can change the thermostat and adjust the wheel angles, so I presume they know what they are doing and will sort out any airlocks as well. So wish me luck! The dents are important for resale value, but only if I can sort them cheaply. The windshield of course has to be changed because it won't pass yearly inspection.
 
If engine sounds fine and runs well it is very likely fine.

Yes possible thermostat jammed open could be cause of cold running.

Oh and if biogas system doesn't work it often works out more expensive to fix than it's worth. Fingers crossed it's functioning for you.
Good luck
 
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The gas system actually operates perfectly. I drove it 300 km to home on a full tank of gas. The fuel consumption seemed a bit high but I guess that's to be expected when the engine doesn't reach operating temperature. It was almost below freezing (in fricking May...) so it doesn't take much to overcool the engine down if the thermostat isn't closing properly.
 
Yes definitely will use loads more fuel if coolant temperature low.

That's a very good sign gas system working perfectly.

118,000km really isn't much at all. It drove back with you 300km , I don't think leak down test necessary but if you want one get one done.

In UK we have very little experience in general of gas systems.
I wonder if it is a bad idea to run them completely empty before refilling.
 
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Yes definitely will use loads more fuel if coolant temperature low.

That's a very good sign gas system working perfectly.

118,000km really isn't much at all. It drove back with you 300km , I don't think leak down test necessary but if you want one get one done.

In UK we have very little experience in general of gas systems.
I wonder if it is a bad idea to run them completely empty before refilling.
Most system will shutdown and switch to petrol I'd the pressure in the tank drops below a threshold so shouldn't really ever get totally Empty after all they use the pressure of the gas to push it into to reducer to go into the engine pretty much the same as a lot system as far as I'm aware
 
That's the great thing about factory setup CNG system, it's fully automated. When the gas tank is too empty, the system simply changes to petrol. It can of course be turned to petrol manually as well simply by pressing a button.

I know 118 000 isn't that much at all. But it's a small engine and if it's been driven with the same oils for the first 66k that's definitely not a good thing. The leak down test was only 40€ extra so it's not going to break the bank and might give some useful information about the health of the engine.
 
The car was at the shop on Monday. They changed the thermostat and oil, because there was too much of it. There was apparently crud from previous use of radiator repair sealant and that was the black stuff on the overflow chamber as well. Oil was just overfilled but I decided to change it to make sure oil looks clean as well. No sign of head gasket issues in the coolant, oils or leak-down test and everything looked healthy according to them. A huge relief.

I was really pleased with the shop. They flushed the coolant system with a washer for half an hour without any additional cost to get any residue and crud out of there. They also fixed the electric fan that apparently wasn't starting when the engine was getting too hot. Simple oxidized connection issue, which I suppose is common with Fiats. The engine temperature remains stable now and warms up quickly.

Now the million-dollar question is why has someone used the sealant previously and if it's going to be a problem in the long run. So for now I'm going to be watching the coolant and oil levels couple of times a week.

They also checked and adjusted the front wheel angles as the car pulled to there right. It improved but didn't go completely away. It almost feels as if the power steering is causing this somehow as a very slight adjustment will correct the steering. Hard to explain. I'm used to driving two generations of ford focuses and they have very accurate steering in my opinion, so I might just be a bit picky.

So now I only have minor issues to solve. There seems to be water inside the rear lights and the brake light are giving an error signal occasionally, so I guess I'm going to have to open them up, check wiring for any rust and somehow seal the casgings. Or maybe I'll drill a small hole to the bottom for the water to go out, this solved a similar issue in my old focus.
 
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The car was at the shop on Monday. They changed the thermostat and oil, because there was too much of it. There was apparently crud from previous use of radiator repair sealant and that was the black stuff on the overflow chamber as well. Oil was just overfilled but I decided to change it to make sure oil looks clean as well. No sign of head gasket issues in the coolant, oils or leak-down test and everything looked healthy according to them. A huge relief.

I was really pleased with the shop. They flushed the coolant system with a washer for half an hour without any additional cost to get any residue and crud out of there. They also fixed the electric fan that apparently wasn't starting when the engine was getting too hot. Simple oxidized connection issue, which I suppose is common with Fiats. The engine temperature remains stable now and warms up quickly.

Now the million-dollar question is why has someone used the sealant previously and if it's going to be a problem in the long run. So for now I'm going to be watching the coolant and oil levels couple of times a week.

They also checked and adjusted the front wheel angles as the car pulled to there right. It improved but didn't go completely away. It almost feels as if the power steering is causing this somehow as a very slight adjustment will correct the steering. Hard to explain. I'm used to driving two generations of ford focuses and they have very accurate steering in my opinion, so I might just be a bit picky.

So now I only have minor issues to solve. There seems to be water inside the rear lights and the brake light are giving an error signal occasionally, so I guess I'm going to have to open them up, check wiring for any rust and somehow seal the casgings. Or maybe I'll drill a small hole to the bottom for the water to go out, this solved a similar issue in my old focus.

Great news you have found a garage that want to help, very nice of them to spend extra time for no extra payment. Next time you are passing by how about giving them some pastries, they will remember that for ever .

Definitely good idea to keep eye on coolant level from now one. I had a car with very slight coolant seepage from heater matrix , incoolant dealer fixed that and didn't block anything else. Few years later I forgot about sealant when changed coolant and after a couple of weeks the seepage restarted .
 
The rear lights seal against the bodywork, chances are you need to take them out (2 screws) and reseat them.

Don’t be tempted to drill holes much better to get it in the right position and dry the lights out before refitting. The wiring has probably corroded as a result so a quick clean up should sort it out
 
Time for a quick update. Due to the pandemic and remote work I haven't really driven the car that much.

New faults I've spotted include dead electric mirror controls and front door speaker. I take it that it's very likely the drivers door wiring loom has come apart. I'll disassemble it and see if it's something I can solder back together or if I have to buy a new loom. Fortunately, there seems to be a connector on the door, so it shouldn't be an impossible task to change.

Another annoying problem is that the heater fan is making an annoying rattling noise. Stays consistent on all levels and on the minimum setting it's almost as loud as the engine. Hoping it's just debris, leaves, and such. I found a tutorial on how to access it under the glove box.

I just checked the oil and coolant level. Unfortunately it seems it's possible the car is losing coolant. It's about 1cm below the midline of the chamber now. That said, I was busy when getting it from the shop and I didn't check the level so I'll have to monitor it in case they didn't really top it. No puddles but it's been warm outside so might be evaporating or leaking into the cabin.

I did manage to get a new remote key cover. A small detail, but I hated the busted up and dirt old one. I also started fixing the cracked boot panel and bought a nifty little device that lets you pull out small dents with hot glue. I'm actually surprised at how effective it was! I just ran out of glue almost immediately so I didn't get to see if I can pull out some of the dents complitely.
 
The coolant is red. I just drove a 50km trip and checked the level of the coolant and it has lowered a bit. I found the leak as there was a damp spot on the engine shield (below the engine). Upon further inspection, I found there was coolant all over the timing belt cover and the belt itself looked wet (assuming that's what I saw through the cover holes...):

view


So it's leaking from the water pump and I'm looking at a full pump and belt change, right? Starting to really regret becoming a Fiat owner... So I guess I'll need to get it back to the shop and cough up the 400e or so this job seems to cost. I might be able to pull it off myself but to be honest I've lost all interest and I'm too busy.

The thermostat job, this leak and the windshield are starting to add up. I hope I can sort out the smaller issues myself and get the value of the car even close to what I paid and invested in repairs.

I'm also having weird tail light issues. The car randomly warns about stop lights (I assume this is the same as break lights) but the lights seem to be working correctly. Earth issue maybe?

Also there's a warning beeper when I put the car in reverse. There are no message associated with it. Is this just a feature? If it is, it's really annoying and can't seem to be turned of through the menus. If not, what could be causing this?
 
The coolant is red. I just drove a 50km trip and checked the level of the coolant and it has lowered a bit. I found the leak as there was a damp spot on the engine shield (below the engine). Upon further inspection, I found there was coolant all over the timing belt cover and the belt itself looked wet (assuming that's what I saw through the cover holes...):

https://drive.google.com/file/d/12A4HYGFv9jJvkIOXq0ENNiy4WTcRLEQQ/view?usp=sharing

So it's leaking from the water pump and I'm looking at a full pump and belt change, right? Starting to really regret becoming a Fiat owner... So I guess I'll need to get it back to the shop and cough up the 400e or so this job seems to cost. I might be able to pull it off myself but to be honest I've lost all interest and I'm too busy.

The thermostat job, this leak and the windshield are starting to add up. I hope I can sort out the smaller issues myself and get the value of the car even close to what I paid and invested in repairs.

I'm also having weird tail light issues. The car randomly warns about stop lights (I assume this is the same as break lights) but the lights seem to be working correctly. Earth issue maybe?

Also, there's a warning beeper when I put the car in reverse. There are no message associated with it. Is this just a feature? If it is, it's really annoying and can't seem to be turned off through the menus. If not, what could be causing this?
 
The coolant is red. I just drove a 50km trip and checked the level of the coolant and it has lowered a bit. I found the leak as there was a damp spot on the engine shield (below the engine). Upon further inspection, I found there was coolant all over the timing belt cover and the belt itself looked wet (assuming that's what I saw through the cover holes...):

https://drive.google.com/file/d/12A4HYGFv9jJvkIOXq0ENNiy4WTcRLEQQ/view?usp=sharing

So it's leaking from the water pump and I'm looking at a full pump and belt change, right? Starting to really regret becoming a Fiat owner... So I guess I'll need to get it back to the shop and cough up the 400e or so this job seems to cost. I might be able to pull it off myself but to be honest I've lost all interest and I'm too busy.

The thermostat job, this leak and the windshield are starting to add up. I hope I can sort out the smaller issues myself and get the value of the car even close to what I paid and invested in repairs.

I'm also having weird tail light issues. The car randomly warns about stop lights (I assume this is the same as break lights) but the lights seem to be working correctly. Earth issue maybe?

Also, there's a warning beeper when I put the car in reverse. There are no message associated with it. Is this just a feature? If it is, it's really annoying and can't seem to be turned off through the menus. If not, what could be causing this?
Oh no )-:
Don't give up you are close to having a really reliable car.
The friendly garage will be pleased to see you and cam belt and water pump kit on that car is straight forward. Plus you have found why it had been filled with leak sesler!

Stop lights = brake lights , yes


Beep when selecting reverse, does it have rear reversing sensors that keep when you get close to something at rear?
 
Thanks for the encouragement, Jack. The car doesn't have reversing sensors or a "parking radar". At least none that I'm aware off and there are no sensors on the back bumper. It's a really annoying high volume beep that lasts about 5 seconds any time I shift to reverse (or take the shifter close to reverse). I guess it could have something to do with the reverse light but it doesn't show an error message or a notification light on the display.
 
Thanks for the encouragement, Jack. The car doesn't have reversing sensors or a "parking radar". At least none that I'm aware off and there are no sensors on the back bumper. It's a really annoying high volume beep that lasts about 5 seconds any time I shift to reverse (or take the shifter close to reverse). I guess it could have something to do with the reverse light but it doesn't show an error message or a notification light on the display.
Ok it's just there to be annoying then , find beeper And unplug it.
 
Turns out that the fluid on the timing belt cover and beneath it is OIL, not coolant. Which means I'm looking at god knows how much additional costs to the repair. Since it's on the belt, I reckon it's probably the cam or crank shaft seal. Can these be changed without disassembling the whole fricking engine? I don't even want to imagine what that would cost. The belt has to be changed either way because it's covered in oil now. Oh and now I don't know where the coolant is going... I guess I'll need to take the car to the shop and pray that's it's something that can be fixed relatively easily...
 
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