T4 2.5 TDI won't start / only starts with brake cleaner

Hello TDI ESP specialists,
My T4 2.5 TDi 102 hp, manufactured in 1996 and with 240,000 km on the clock, won't start.
On Saturday, I went on a trip that was over 1200 km. Around 600km into the trip, I stopped, and the bus started up again after only 5 seconds of cranking (a problem I had never encountered before).
The next morning, the car simply wouldn't start. It just whirred.
I had it towed to VW (my friend's place).
Relay 109 is OK.
The solenoid valve is 12V and it's clicking, but I haven't removed it yet.
Diesel is still here; I changed the diesel filter today.
But when starting, no diesel fuel is reaching the injectors.
The small timing belt is also fine.
Today, we managed to get the bus running again using brake cleaner.
I turned it off again, but it just wouldn't start.
Brake cleaner again.
Then I warmed up the T4, and now it's still hesitating and not running smoothly after about 4 seconds.
My friend, who is a mechanic at VW, said that the ESP system cannot maintain the pressure needed to start the engine.
What is the cost of ESP repairs at Bosch?
I can get an AT pump for 972€.
Or could you please let me know of any other cost-saving measures?
Bye Klaus.

A friend of mine had his fuel pump refurbished by Bosch in Darmstadt, and it cost him around 400 euros. I think it also depends on what exactly is broken on the pump.

Hi,
What is the starting speed?

'I just had this [car] serviced (248,000 km, returning it on Monday). The cost was €1385.63. I also had the timing belt replaced at the same time, but you now have a good car. They didn't find the problem at my place until the third inspection!'

Here are a few more facts.
1. So, I've never put biodiesel, rapeseed oil, or any other junk in my car since it reached 187,000 km.
2. All the fuses are fine.
3. The error memory showed zero errors.
4. I loosened a diesel line when starting the engine.
Nothing happened.
5. The ESP timing belt is fine; nothing has jumped.
Valve timing is okay.
When the engine is running, it works perfectly and there is no hesitation.
or rust, and do so at high speed with full power.
It only runs roughly when idling.
6. All the hoses are where they should be.
7. The diesel fuel is flowing properly from the tank through the diesel filter, when it actually runs. This can't be right.
8. The diesel engine arrives at the pump without any issues. So, everything is working properly.
9. The performance might have been slightly different on the return journey.
Left behind. Approximately 5 km/h, only 170 (something else, unclear).
175-180 km/h. However, it could also be due to the weather conditions.
But when accelerating, you don't notice anything.
10. There's something strange about the engine speed when starting.
When the engine is warm and starts after being cold, the tachometer shows approximately 250 RPM.
When the engine is cold and doesn't start, it doesn't show any RPM when cranking.
Very suspicious.
Bye Klaus.

Keyword:

Crankshaft sensor (it should be labeled G28).

Here's information from the 3.3 V8 TDI SSP (Service Software Package).
http://www.luxus-wg.de/~martin/auto_bilder/Geber1.JPG


But if there's a problem, it should also be stored in the error memory.

m;

However, there are no error codes stored in the system.

"No entry" doesn't necessarily mean "everything is okay."

You might actually have to go further and check some sensors (and the G28 is essential for the TDI) from the outside, using an oscilloscope or something like that...

Sure, here's the translation:

"Just a tip."

m;

Klausen wrote:

10. There's something strange about the engine speed when starting. When the engine is warm and starts after being cold, the tachometer shows approximately 250 RPM. When the engine is cold and doesn't start, it doesn't show any RPM when cranking. Very suspicious. Bye Klaus

If the advertisement is correct, that would be the cause of the problem. Below a certain RPM (there's a search function somewhere here, but I'm too lazy to look), the pump doesn't inject fuel. Using brake cleaner, you might just exceed that limit when the engine is cold, but it starts more easily when it's warm.

However, there is nothing/niente in the error memory.


doesn't have to...

This is an inductive generator, meaning it produces only a small voltage at low speeds, but generates a voltage of over 100V at high speeds.

You can only check the sensor for total failure or short circuit, but not for correct function, especially during startup.

It might be worth a try...

CU Gremlin.

If the advertisement is correct, that would be the cause of the problem. Below a certain RPM (search function, I think I saw something about that here, but I'm too lazy to look), the pump doesn't inject. Using the brake cleaner, you might just exceed that limit when the engine is cold, but when it's warm, it starts more easily anyway.

'Perhaps it would also explain the warm-up process...'

The D-pump was defective.
It was very easy to get it started, and the used one started up perfectly right away.
Something about the high-pressure side.
Thanks again for your tips.

Bye.

Hello.
It's not uncommon for the two valves in the high-pressure section to break. This has the effect that the pump plunger is no longer returned to its starting position. Consequently, no diesel fuel can be pumped. However, if the engine is already running, it seems that pushing the plunger back into place is sufficient. Perhaps it would have been enough to have the vehicle towed to a pump service center. The damage can be repaired for approximately 300 euros, including adjustment and sealing. But only with a qualified Bosch service center.
Symptoms: Difficulty starting, requiring several seconds to turn over. The same effect occurs whether the engine is cold or warm. There is smoke emitted during and especially after starting. Slightly increased fuel consumption or a slight decrease in performance. The error message doesn't necessarily have to be present, but if there are things like quantity controls, etc.

Best regards, Heri.

Yes, exactly, the spring is broken and it has shattered the pump plunger.
1100€ was promised, but in return, you get a VW auxiliary water pump.
Why does the pen break?
Could it be related to the driving style? For example, driving with the engine running at low RPMs and then suddenly accelerating hard?
Best regards, Klaus.

One more thing.

He never smoked, though.
It only started with the help of starting spray.
Warm up before playing.
Power loss, yes, approximately 20 km/h at high speed.
Increased fuel consumption was not detected.
Best regards, Klaus.

P.S: I'm still looking for a similar, affordable fuel pump (ACV, year 1997, 2.5 TDI T4). Possibly defective.

The feathers likely break simply because the material has become fatigued. However, this has nothing to do with low RPMs. The reason he didn't experience any smoke is that the system wasn't delivering any fuel at the idle speed. Even when the engine is not starting properly, diesel fuel is still being injected into the cylinder, which is then expelled when the engine eventually starts.
It's unfortunate that the plunger is also defective, as that likely means the high-pressure component has also been damaged. Just the feathers themselves aren't the problem.
I got a price of just under 900 for the AT pump from somewhere.
You can find Occ-Pumpe pumps at the butcher's shop or on eBay.
Best regards, Heri.