Car Enthusiast Club [Now Motorcycle friendly!] - First thread to 150k! ¯\_(ツ)_/¯

[Bitter]

Turned my brakes black with heat getting the rust off and pads bedded for summer.

[BetteBalterZen]

Hey everyone! 

I'm looking for for some - hopefully - educated guesses on if my 2015 VW Polo 90hp TDi is working as intended. 

I have now owned this Polo for a 1.5 years, bought it used obviously, and I'd say I'm pretty good at noticing when different dials are different than normal and so on. About 2 months ago I started noticing that the water temperatur (I think it's water temp) started rising above the normal operation temperature of 90C when first started driving. I saw in normal city traffic and if I got quickly onto the highway. First it started out by rising to 95-100C, and then through the past two months it has gotten worse and worse. 110C was usually hit when first hitting the highway fx. But everytime the temperature rised above 90C, it would hover there for a few minutes and then fall down to 90C and stay there until my drive is done, doesn't matter how far I drive or if I'm driving 50kmh in a city or 130kmh on a highway. But as I said, it got worse and worse. Then last week, after driving home from work, the temperature hit 130C and my car alarmed me saying I had to shut down the engine ASAP and when this happened, I started braking (no traffic behind me) and as soon as I hit the brakes, the temperature instantly fell down to 90C like nothing was wrong, and I was able to drive all the way home, on highway at 130kmh, no problems whats so ever. 

But because of the 130C, I went to the auto repair shop and they tested my cooling system for exhaust gasses because it could have been a part starting to break which would have causes the exhaust gas to leak into the cooling system but luckily this was not the case, so what they did was to swap out the sensor in the cooling system (sorry, not entirely sure what it is called) and this have improved this issue a lot. Notice I say improve because I still see the temperature hit 95-100C if I hit the highway really quickly after a cold start but it no longer hovers there for multiple minutes and before with the old sensor the temperature always hit 110-115C on the highway and hovered there for some minutes, so yeah, huge improvement. Also when driving in the city now, I have yet to see it go above 90C which it started doing always before with the old sensor. Again, huge improvement. 

But now to my actual question; hitting 95-100C for a brief moment on the highway just after a cold start, is this normal or does this still indicate a problem? Maybe this is actually normal and my car have done this always, maybe I just haven't noticed it before two months ago, where it just also started being worse and worse. 

I know that these sensors thingys are parts that get worn down over time and is expected to fail after some years. 

And last thing; if this thread isn't supposed to be a helping thread, then I'm sorry

Good day everyone. 

[JoaoPRSousa]

7 hours ago, BetteBalterZen said:

- snip -

 

That is definitely not standard behavior, at first I thought the issue was the thermostat, the E39 I've been driving around notoriously dips below normal temperature when on the highway due to the thermostat staying open. Could be the thermostat failing on your Polo too, it fails to open so the water that is in the engine doesn't move to the radiator to get cooled off, resulting in overheating. Logically, it makes sense, but the improvement that came with replacing temperature sensors doesn't make much sense to me.

It is rather weird too that after braking, the engine went back to normal on that situation you mentioned.

I'd suggest taking it to somewhere just to check the thermostat's condition (if that is even a thing) or just replace it completely and see if that solves it.

[BetteBalterZen]

1 minute ago, JoaoPRSousa said:

 

That is definitely not standard behavior, at first I thought the issue was the thermostat, the E39 I've been driving around notoriously dips below normal temperature when on the highway due to the thermostat staying open. Could be the thermostat failing on your Polo too, it fails to open so the water that is in the engine doesn't move to the radiator to get cooled off, resulting in overheating. Logically, it makes sense, but the improvement that came with replacing temperature sensors doesn't make much sense to me.

It is rather weird too that after braking, the engine went back to normal on that situation you mentioned.

I'd suggest taking it to somewhere just to check the thermostat's condition (if that is even a thing) or just replace it completely and see if that solves it.

Thank you for your input. 

I must admit that I am not sure if the sensor or thermostat was changed. I honestly can't remember now... Anyhow, again, thanks for your input. I will call the mechanic tomorrow and explain how everything has improved but still not perfect. 

[Bitter]

Also dash gauges aren't always very accurate, they're kind of made for the dumb masses. Some gauges are non linear so they rise and fall irregularly, 20 degrees could be 1/4 swing on the gauge for one temp range but from day cold to 60C might be 1/2 of the sweep. You'd probably need to look at actual temp from the computer data.

[Bitter]

This came in for a gas tank.

[Stahlmann]

On 4/20/2022 at 4:04 PM, iDeFecZx said:

Ouch, think we've had one or two like that.

My car is in for repair right now. That at least gives me the opportunity to test drive an VW ID3 for the duration of the repair. I gotta say i'm pretty sold on EV's now. I was pretty sure that my A3 was gonna be the last ICE car, but now i'm sure of it. The space-ship-like sound at low speed (or lack of noise at higher speed), comfort, power, etc. It's all there.

[bcredeur97]

22 hours ago, Bitter said:

This came in for a gas tank.

Ok hang on a second… is he trying to power an entire city with his car? Lol 

[Bitter]

55 minutes ago, bcredeur97 said:

Ok hang on a second… is he trying to power an entire city with his car? Lol 

Stock alternator and 2 others are DC for the CB radio and vehicle power. 3 other alternators are AC power 'fo when the lights go out ya know' he said with a chuckle.

 

Started pulling my bumper tonight to replace my low beam bulbs, I did not get as far as I had hoped before I gave up for the night. Too tired, I know I'll get sloppy or I'll keep working until I'm just done AND get sloppy. I don't want to screw up, do things twice, break stuff, etc. I also just really like how this picture came out.

 

[Bitter]

Bwahahahaha new HID bulb is minimum 50% brighter than the old bulb on the other side, maybe more like 75%. I didn't realize how bad they were!

[iDeFecZx]

Finally done the plugs on the 240, look pretty good to say its constantly abused and running over 100hp more than stock.

Got my next trackday booked to, heading to Anglesey at the end of August so should be fun

Been quiet recently as this happened

[ben.is.kill]

 

Just sharing a pic of my car (will post some progress maybe in the following months).

I also have a Yamaha YBR250 motorcycle.

[Colty]

On 5/4/2022 at 12:45 AM, BetteBalterZen said:

-snip-

The part that would have had the exhaust gases and coolant mixing would be your EGR. I'm not sure how common it is on the Polo's, but I've seen a handful of very high mileage (350k+) TDI mk5 Jetta's with that issue. Though, most opt to delete the EGR and call it good. 

Your thermostat could be intermittently sticking, you could have a bad wire to the sensor, ect. It'd also be worth finding out if the gauge on the dash is a "dummy indicator" or not. It's normal to experience slight variations of coolant temp. Most brands switched to a dummy indicator. Your car likely isn't going to hold 190f (middle gauge for me) all the time, but you don't need to spook someone and show the 200f. So now when they are at 180-210f (or whatever) they say "190f, you're totally fine." My old VW Scirocco has a real gauge and it's alarming at times because I'm used to dummy gauges, but then I remember it's normal and just keep driving.

The next step for diagnosis would probably be to check for hot spots, maybe do a coolant flush if it's never been serviced? Does the TDI motor in that Polo use a timing belt like most other small displacement VW TDI's? Could it be due for a timing belt/water pump (typically every 120k)? 

[bcredeur97]

4 hours ago, Colty said:

The part that would have had the exhaust gases and coolant mixing would be your EGR. I'm not sure how common it is on the Polo's, but I've seen a handful of very high mileage (350k+) TDI mk5 Jetta's with that issue. Though, most opt to delete the EGR and call it good. 

Your thermostat could be intermittently sticking, you could have a bad wire to the sensor, ect. It'd also be worth finding out if the gauge on the dash is a "dummy indicator" or not. It's normal to experience slight variations of coolant temp. Most brands switched to a dummy indicator. Your car likely isn't going to hold 190f (middle gauge for me) all the time, but you don't need to spook someone and show the 200f. So now when they are at 180-210f (or whatever) they say "190f, you're totally fine." My old VW Scirocco has a real gauge and it's alarming at times because I'm used to dummy gauges, but then I remember it's normal and just keep driving.

The next step for diagnosis would probably be to check for hot spots, maybe do a coolant flush if it's never been serviced? Does the TDI motor in that Polo use a timing belt like most other small displacement VW TDI's? Could it be due for a timing belt/water pump (typically every 120k)? 

According to everyone online I should be waiting for my Oil Cooler seal to fail on my 2012 Touareg 3.0L TDI and my car to puke coolant everywhere.


Which is buried here:



That will be a FUN day! 

[BetteBalterZen]

10 hours ago, Colty said:

The part that would have had the exhaust gases and coolant mixing would be your EGR. I'm not sure how common it is on the Polo's, but I've seen a handful of very high mileage (350k+) TDI mk5 Jetta's with that issue. Though, most opt to delete the EGR and call it good. 

Your thermostat could be intermittently sticking, you could have a bad wire to the sensor, ect. It'd also be worth finding out if the gauge on the dash is a "dummy indicator" or not. It's normal to experience slight variations of coolant temp. Most brands switched to a dummy indicator. Your car likely isn't going to hold 190f (middle gauge for me) all the time, but you don't need to spook someone and show the 200f. So now when they are at 180-210f (or whatever) they say "190f, you're totally fine." My old VW Scirocco has a real gauge and it's alarming at times because I'm used to dummy gauges, but then I remember it's normal and just keep driving.

The next step for diagnosis would probably be to check for hot spots, maybe do a coolant flush if it's never been serviced? Does the TDI motor in that Polo use a timing belt like most other small displacement VW TDI's? Could it be due for a timing belt/water pump (typically every 120k)? 

Hi Colty

Thank you for your input! 

Alright I see. This is my first time looking at a EGR. Again, I'm a 100% rookie when it comes to cars and engines specifically. The mechanic that worked on my car did check the cooler for exhaust gasses and luckily none was found. When you say most opt to "delete the EGR", what exactly does that mean? Like removing the part from the engine or from the computer so that the car does no longer report high temperares because of this part? 

One of my good friends also said that my thermostat might have been "hanging" which maybe could be the same thing as sticking, like you say. maybe?. Anyhow the mechanic changed the thermostat and it improved the issue so much! I even today was able to drive to work with the temp only peaking at 94C, even though I hit the highway very fast and with a cold engine. Seems like the issue has been fixed. 

Anyhow I have no clue if the indicator is a dummy, and I have no clue on how to figure this out. But if it's a dummy, does that mean that the temperature it reports is false? 

My Polo have had all it services done and my cooling have been changed before. Also I'm pretty sure it has a timing belt yes and I honestly don't know if this has been changed before. 

Thanks again for your input!

[Colty]

10 hours ago, BetteBalterZen said:

-snip-

The EGR is an emissions item. "Exhaust Gas Recirculation" system. Lots of people delete it as it will improve efficiency and increase reliability. Typically though, you remove it when it fails assuming you don't need to pass inspection. The EGR delete can include an adjustment to the computer to make the engine not report an "incorrect flow" and throw a check engine code. 

Glad to hear the thermostat fixed it. As for the "dummy switch." It's not that it would be false, it's just that a safe temp will read as 190f so you don't get worried when it goes from 180f-200f, which is normal, but can spook people. Think of it as "190f" (or whatever is in the middle) just means it's in the safe range

[BetteBalterZen]

1 hour ago, Colty said:

The EGR is an emissions item. "Exhaust Gas Recirculation" system. Lots of people delete it as it will improve efficiency and increase reliability. Typically though, you remove it when it fails assuming you don't need to pass inspection. The EGR delete can include an adjustment to the computer to make the engine not report an "incorrect flow" and throw a check engine code. 

Glad to hear the thermostat fixed it. As for the "dummy switch." It's not that it would be false, it's just that a safe temp will read as 190f so you don't get worried when it goes from 180f-200f, which is normal, but can spook people. Think of it as "190f" (or whatever is in the middle) just means it's in the safe range

Thank you for the explanations

[bcredeur97]

Did someone say *cough* delete *cough* ? 

[Bitter]

Who else prefers coolant creamy style?

 

 

[IPD]

<Begin Rant>

 

~4+ years of being fed up with the lack of QUALITY electric motorcycles offered in the USA--and I pulled the trigger on an Evoke Urban S.  So we'll see in a few months how I like it.

 

Idk wtf manufacturers are smoking--but it must be some good shit.  Most of the big manufacturers aren't even offering electric motorcycles (let alone electric bikes).  The ones that do, are expecting people to plunk down Honda Goldwing sized piles of touring-bike money on something that is most clearly intended for, should be designed for, and functions best as---a commuter bike.  Even Zero is barking up the wrong tree here--with their "city-bike" (45mph) being the only thing under $10,000 USD they sell.

 

This has been a known quantity for years.  Consumers saying "electric motorcycles look interesting"; the reservations are all the same.  Top speed is too low.  Range isn't good enough.  Design looks like something from a 1970's buck-rodgers set.  Cost is new-car territory.  And while there are some city-bike offerings in the ~$4000 range, from there you need to plunk down at least $12-13,000 for an electric bike that will at least do 70mph.  And that's if you want only a Zero.

 

According to the manufacturers--there is zero demand for an electric motorcycle priced between $4000 and $20,000.  This, despite years of consumers and enthusiasts screaming that they all want a $10,000 (or less) option.  This despite Tesla making huge inroads in electric cars--proving that demand exists.  This despite China and other areas in the world handily demonstrating the demand and profitibility to be had from a low-cost electric motorcycle that can reach highway speeds.

 

So instead of Harley breaking its mold and bringing new buyers into the fold for a company whose quality/technology/bang-for-buck is already tepid; instead of Honda turning it up to 11 and delivering what Honda does best; instead of KTM, BMW, Kawasaki, Yamaha or Indian trying to be an early adopter to a new market; and instead of Polaris bringing back the defunct Victory brand just so they have a legitimate electric-only motorcycle brand to offer--instead of all that, we got jack and squat.

 

So as much as I hate "unknown" brands from China, or gambling with my money, or sending my hard earned money to China in the first place--I don't have sensible alternatives.  I'm done waiting on a market that is cluelessly drunk behind the wheel.  I want a bike to get to and from work.  That's it.  Safe to merge.  Range that can get me there and back without issue.  And no internal-combustion engine.

 

/Rant

 

p.s.

Hand to god, if I were already retired, I would be on the phone with Evoke right now--trying to set up their first dealership in the lower 48.  This market segment is criminally neglected--and I would personally love to rub that in the faces of all the big, smug, established brands.

[Bitter]

Stupid CAN'TBUS. Finally got this 10 Traverse to not start and stay not starting and finally pinned it down to a bad antilock brake module...but possibly a bad onstar module too.

[vf1000ride]

1 hour ago, IPD said:

<Begin Rant>

 

~4+ years of being fed up with the lack of QUALITY electric motorcycles offered in the USA--

 

Unfortunately for both 2 and 4 wheeled electric vehicles I have no real interest in either of them until they have a 4-500 mile uncharged range.  Even that is pushing the low end of what I would want out of one.  I have on multiple occasions done 400+ mile one days rides on the motorcycle and 600+ miles in a day in the car is not out of the question. 

[bcredeur97]

20 minutes ago, Bitter said:

Stupid CAN'TBUS. Finally got this 10 Traverse to not start and stay not starting and finally pinned it down to a bad antilock brake module...but possibly a bad onstar module too.

Lol that’s ridiculous. Brake module should have nothing to do with the starter. It’s supposed to be a different server on the network! In layman’s terms…. 

 

this stuff doesn’t happen with normal tcp/ip networks I don’t understand why cars have to be so different. 

[Bitter]

42 minutes ago, bcredeur97 said:

Lol that’s ridiculous. Brake module should have nothing to do with the starter. It’s supposed to be a different server on the network! In layman’s terms…. 

 

this stuff doesn’t happen with normal tcp/ip networks I don’t understand why cars have to be so different. 

Save on wiring, network passes THROUGH the modules from one to another like an old token ring network. ABS is on high speed data because it needs near real time information for abs/trac and to talk to the trans and ecm to know gears and throttle and to tell the ecm to limit throttle or trans to hold a gear for traction stuff. It IS really dumb that it would make the car not start, but the EBCM is between the engine, trans module and the body module. So no EBCM, the body module can't do security with the ECM to start the engine.

[bcredeur97]

3 minutes ago, Bitter said:

Save on wiring, network passes THROUGH the modules from one to another like an old token ring network. ABS is on high speed data because it needs near real time information for abs/trac and to talk to the trans and ecm to know gears and throttle and to tell the ecm to limit throttle or trans to hold a gear for traction stuff. It IS really dumb that it would make the car not start, but the EBCM is between the engine, trans module and the body module. So no EBCM, the body module can't do security with the ECM to start the engine.

I guess it would be a lot more wiring to run a twisted pair from every module to a switch 

 

especially since some fancy cars have like 90 modules