Golf 3 TDI: Engine Overheating? Troubleshooting

Hello,
I recently bought a VW Golf TDI.
Now, I'm having the following problem.
The car either doesn't reach its maximum speed, or it only does so with great difficulty.

Around 140-150 km/h, it doesn't accelerate as well anymore.
It feels like it's getting fuel in spurts, not consistently.
It only happens at top speed. If I rev it to 4000 RPM in 2nd or 3rd gear, there are no noticeable power dips.
It's amazing, like a rocket (compared to the old Fiat Cinq with 55 horsepower ).

What could be the reason for that?
Usually, everything is fine up to 140.
The hoses in the engine compartment seem to be secure, as far as I can tell.

Even the workshop foreman was at a loss.
but he tapped the diesel filter (although he wasn't sure about that either).


I'm going to go to ATU tomorrow and have them read the error codes. Maybe something will show up.

According to the expert, it can't be the LMM (likely referring to a specific component), because otherwise I would constantly be experiencing a lack of power.

(By the way, it doesn't hurt him.)


Sincerely,
Jan.


I hope you can help me.

. . . back to the load balancing.

Hi,

Depending on the year of manufacture, the engine control unit for the 90 hp engine, if it experiences excessive boost pressure (which is most likely to happen in the highest gear, because the engine speed is least likely to "outrun" the turbocharger), does not, as far as I know, enter a permanent limp mode, but instead reduces the fuel injection amount only until the pressure returns to the target range.
Then the full amount is released again, the pressure rises too high again, etc.

This could be easily and clearly checked with a boost pressure gauge.

Otherwise, please check all the hoses around the boost pressure solenoid valve, or consider replacing the valve as a precaution.

Sometimes, the error memory also provides clues in the right direction.

Diesel filter replaced -> partial success. The symptom is not as severe as before.
Error codes read -> Nothing found.

I'll keep an eye on it.

This pneumatic pressure charging valve is okay.
The mechanic at ATU and the one at VW also ruled out the valve.
because it would result in greater losses.

According to their opinion, ultimately only the LMM (likely referring to a specific device or component) is a viable option, but for cost reasons, I'll probably only clean it occasionally, if at all.
A new one is too expensive for me right now.

Hi!

However, despite what your mechanic says, I would almost certainly suspect the boost valve!
And that's for a very simple reason:
At a mileage of 130,000 kilometers, my Golf 3 TDI with 90 horsepower exhibited exactly the same issues:
Around 140 km/h in 5th gear, the engine stopped producing power – it felt like an extremely strong gust of wind was hitting you head-on.
After briefly letting off the gas and then immediately flooring it again, it worked (for a few seconds).
The turbocharger control valve was replaced in the workshop - since then, everything has been running smoothly again!
It's not that expensive, so I'd give it a try!

Of course, without any guarantee .

Markus.

Hello,

Thank you for your contribution, Markus.

I'll have the valve replaced.

costs approximately 75 euros.
You can exchange it yourself!

Just disconnect 3 hoses and one plug, and then plug them back in .

Arne.

@Arne: Are we talking about the same valve?

I just ordered the part from VW over the phone; it costs €55 including installation.
The part itself costs €29.90.

I'll install it myself, of course. I'm not completely useless.

Actually, I could look it up myself, but I'm not getting any prices displayed in AKTE.
if someone could help me with that, that would be great .



Does anyone happen to have the number for the valve?
I can't find anything under the term 'Ladedruck' in AKTE.

The only thing I've found is...
Is that a solenoid valve?

...it also only cost me 25.25 euros (+ a ridiculous surcharge).

The invoice states 'Solenoid valve,' and the part number is:
028 906 283 F.
I would be careful with that number.
Wer weiß, ob Du genau dasselbe Teil brauchst - hängt ja auch manchmal vom Baujahr ab. Mone is from 1995.

By the way, if you install everything yourself, you can save about 60 euros!
Congratulations!
Of course, the VW technicians checked all the systems beforehand, even though they probably had a good idea where the problems would be. And that, of course, comes at a cost.
If only there had been one line item for 'System check windshield wipers'...

Good luck.

Okay, so I quickly removed the valve today.
After that, I went to the highway to test it out.
The issue with the wave-like acceleration is now resolved.
I reached a top speed of approximately 182 (according to the speedometer).
He reached it after approximately 3 kilometers from the highway exit.
It goes really fast up to 160, but after that, it's rather slow.

Could there be something else wrong? Or could it be related to the fact that I now have 195 tires on 15-inch rims instead of the 185 tires on 14-inch rims I had before?

What makes your 90 horsepower model so great?

G3-TDI wrote:

What makes your 90 horsepower model so great?

Hi.

My wife's ALH Ibiza reaches approximately 185 km/h after a few kilometers of acceleration, but that's a "real" speed (on a flat, straight highway with no noticeable wind).
At a normal, slightly accelerated speed, that would probably be around 195 [km/h or mph].

180 entries have been registered.

Hi!

Engine: The good old 1Z.

Once it's properly warmed up, it reaches a speed of 195-200 km/h on a flat road (which is all you find in the Rhineland...).

@ G3-TDI:
Your test, which resulted in 182 km/h, sounds like it involved a rather short warm-up period (test briefly, then immediately onto the highway).
Then it's not working for mine either.
I haven't done something like that in a long time.
I just feel too much sympathy for the engine, which has to fight against the brutal frictional forces.
Since I drive 130 km on the highway every day, I have plenty of time for high-speed driving.

I can't think of any other defects.
It's possible (since your Golf is likely used), that it wasn't properly broken in, or that it was driven mostly on short trips.

Hello Jan,

Perhaps you could let a friend drive your car and follow it at top speed to check the amount of soot your car is emitting.
If it's producing black smoke at top speed (full throttle), the engine might not be getting enough air. In that case, you should check the turbocharger system for leaks and inspect the EGR valve to ensure it's sealing properly and not allowing pressurized air to escape into the exhaust.
Here as well, you should monitor the boost pressure. If the boost is too low, the mass airflow sensor will report insufficient airflow to the engine control unit, which will then reduce the fuel injection amount. In this case, you should further investigate the cause of the low boost pressure (e.g., wastegate, control hoses?).
If the boost pressure is correct, but the mass airflow sensor (MAF) is still showing low values (a diagnostic tool is needed to check the MAF and boost pressure), you can try cleaning it or, for testing purposes, installing a different one.
In this case, also check for leaks in the intake manifold between the turbocharger and the mass airflow sensor, where unmetered air could be drawn in, bypassing the MAF sensor.
If there's absolutely no smoke, your diesel filter might be "blocked," meaning the engine isn't getting enough fuel injected into the cylinders. Of course, the engine can also receive insufficient fuel due to leaks in the fuel lines. Therefore, you shouldn't see any large air bubbles in the transparent fuel line between the diesel filter and the fuel injection pump.

Best regards, Rainer.

Hello Rainer!

I am very grateful for your last post.
Allerdings richtete sich Deine Hilfestellung sicher an 'G3-TDI'. Or what?
Because he's experiencing performance issues with his car!
My 1Z purrs up to 200 km/h - so, no problems.

Markus.

Oops, exactly .

I've also heard that the catalytic converter can become clogged with high mileage, which can prevent the vehicle from reaching its top speed. I know someone who experienced this gradually, until they could no longer reach speeds above 160 km/h.
@G3-TDI: Could it be that? *not entirely sure myself*

What should a catalytic converter be clogged with? Soot? In that case, the engine would have been running with a lack of air for a long time, so that the catalytic converter wouldn't be able to oxidize the soot anymore. How about trying a tank of biodiesel and then really burning it off (2 hours of full throttle on the highway, preferably at night). I've heard of 'sulfation' of catalytic converters, which is caused by the sulfur in diesel. However, this is supposed to reverse if you use sulfur-free fuels and also let the catalytic converter get really hot (full throttle on the highway). However, sulfation is only supposed to reduce the effectiveness of the catalytic converter; I haven't heard anything about it causing clogging.
That would be a perfect opportunity to really go all out again.

Regards,

Eike.