Golf 118 TSI Engine Failures and Service Campaign 24S4

[prise]

Can you take a quick peek at tsi.txt and tell me what group will give Air Fuel Ratio?

You want to get the lambda value. A lambda of 1.0 means the mixture is stoichometric (~14.7:1), less than 1 is rich, more than 1 is lean. Sometimes it is displayed as an equivalence ratio which is the inverse. The easy way to work out what is being displayed is to check and see if the reading goes above or below 1.0 at high load and RPM. If it goes down below 1.0 it will be lambda, ie getting richer.

I would start with:

031,1,Lambda Control,Bank 1 (actual)
031,2,Lambda Control,Bank 1 (specified)

This should give you the target value and achieved value. If pulling a raw sensor reading then you should take the one before the catalyst which would normally be sensor 1.

In combination with the RPM, manifold pressure and ignitiion timing info you have already identified it should give a pretty good indication if any significant changes to maps have been made. Theres some other interesting data there on the knock sensing but its going to be impossible to interpret the readings unless we had access to the interface spec for the sensor.

I assume that you will wait until the coolant temperature has stabilised and try to repeat the test at a equivalent ambient temperature.

[logger]

Thanks Prise. Just got my car done. I grabbed some "before" logs including 12 parameters including the Lambda as you suggested. Post update I was initially snookered, because the reflash changes the reported ECU program from mark G to mark BA. This meant VCDS could not do the advanced measuring values. So I have just corrected my label files to reflect this. It is all working again and I can see everything I want to. Nothing obvious but I have only done a 5 minute real quick after mod log. So there is not enough info to really compare. Cursory look shows max loads and max EGTs are still the same. Car feels gutless but this is most prob because I disabled the APR tune 24 hours ago to test, pre flash. So anything will feel gutless by comaprison. About to go for a 200km drive and will try to do some better logs. Will report back.

[coastie]

How Many KMs? 26570
Do you mainly do a lot of short trips? No 38 km to work most days
Do you mainly do fewer longer trips? No weekend mainly 250 kms runs
Do you alway drive in a gentle manner? No
Do you flog the car and give it a bit of a hiding from time to time? Not really
Do you only use 98Ron fuel? Yes
What is your car build date?[/QUOTE] Dec 08


Have had the supercharger clutch replaced and the DSG Mechatronic unit replaced.

[nicandlance]

Ok, all this technical talk is baffling me a bit... the question is...
after having this update done, are we guaranteed that our engines won't blow up?
I (and I'm sure many others), have taken a big risk choosing this car - one that we thought was a quality machine... (well, on paper anyway)
Am I going to regret this in a few years time?

[DracZ]

Ok, all this technical talk is baffling me a bit... the question is...
after having this update done, are we guaranteed that our engines won't blow up?
I (and I'm sure many others), have taken a big risk choosing this car - one that we thought was a quality machine... (well, on paper anyway)
Am I going to regret this in a few years time?

Shouldn't you be speaking to VW about this? I understand your concerns, but no one here is in the right position to give you any guarantees with this particular issue.

[Brendan_A]

VW are not going to tell us the truth even if we asked them.

[prise]

Ok, all this technical talk is baffling me a bit... the question is...
after having this update done, are we guaranteed that our engines won't blow up?
I (and I'm sure many others), have taken a big risk choosing this car - one that we thought was a quality machine... (well, on paper anyway)
Am I going to regret this in a few years time?

Nic, recalls and SW updates are unfotunately a fact of car ownership these days. Every one of the four new cars I've owned previously has had some type of defect that has neede to be rectified and my last car also had a SW update to correct problems with an incorrectly calibrated sensor. This didn't stop them being dependable transport dopwn the track after they had been 'de-bugged'. In this day of internet and instant communication we get to hear about the 1 in a 1000 case where a mechanical failure occurred whereas 10 years ago we would have been blissfully unaware. Ultimately you are relying on the knowledge and backing of one of the worlds largest car makers that has already made over a million TSI engines.

[Corey_R]

There were 2 recalls on my Toyota Echo before I switched over to VW. My brother's Ford Territory has a recall on it too. Not sure there is any car company that hasn't had recalls.

[hooba]

There were 2 recalls on my Toyota Echo before I switched over to VW.

I can't believe you admitted to having once owned an Echo.....

[Corey_R]

Yeah, it was a blue Sportivo model. Got it when it first came out at the end of 2001. Would have loved to have got something better, but it was hard as someone in early 20's with a mortage already. Was a great car though. Could fit 6'3"+ friends in the back. I moved my 42" Plasma in it a few times. I also sold it for over 50% of it's new purchase price after 7 years! lol

[nicandlance]

Shouldn't you be speaking to VW about this? I understand your concerns, but no one here is in the right position to give you any guarantees with this particular issue.

I wouldn't expect an honest answer from VW... would you?

[logger]

I am open minded to as to the cause by the way. I have a hunch related to emission controls, not fuel, but will not be able to check until I see how my car compares after any ECU "fix" via VCDS. Anyone know at what part of operating regime this engine is exposed to the greatest heat stress?

Eureka. I think I can now confirm my hunch to be the case. Noticed something with the 118 about 6 months that, coming from a background of operating gas turbines, really surprised me. I susequently logged and recorded it again back when the tsi eng fail thread was here, before it got sanitised and erased. I nearly mentioned it to the protagonists, but thought they would scoff at me if I mentioned it. Anyway post SC 24S4 it clearly no longer has this extreme characteristic. Just got to check it once again and will report back later.

Suffice to say it is nothing to do with fuel types and all to do with aggressive emissions control.

BTW I ran some good long 20 minute drive logs with SC 24S4 last night and I cannot see any obvious changes in the parameters. This might be because I am missing something, but I think it is more because SC 24S4 changes nothing there.

[DracZ]

I wouldn't expect an honest answer from VW... would you?

And getting a false sense of security via someone who has no authority on the subject would be useful how?

[prise]

Anyone know at what part of operating regime this engine is exposed to the greatest heat stress?

Logger,

In response to your question, the worst heat stress is normally at WOT and max RPM (maximum gas flow). Most manufacturers tip in extra fuel at this condition to protect exhaust valves, cataytic converters, etc. You might be interested in the following quotes from VW's self study programme material for the dual charger engine:

"Up to now in petrol engines, the mixture was enriched
early due to the high exhaust gas temperatures.
The exhaust manifold on the 1.4l TSI engine is
designed for exhaust gas temperatures up to
1,050 °C. As a result, the engine can be run with a
high boost pressure and with Lambda 1 in almost all
map ranges."

and

"Due to the higher exhaust gas temperatures, the
outlet valves are filled with sodium for better heat
transfer. This reduces the temperature at the outlet
valves by approx. 100°C."

[parso_rex]

I'll bet that they don't run at Lambda 1 across all ranges now