Starting From Warm...

lil_pidge

Active Member
Aug 12, 2008
13
0
Also have a very lumpy idle on my 2.0 TDI 140bhp. Dealer(s) have had several 'looks', but can't find anything wrong. Just gone out of warranty (60k+ miles - 2 1/2 years old), so will be interesting to see what a real mechanic finds at the next service!!
 
just done a search on the net for this. found the following about the Vw BKD 2.0 TDI.

http://www.justanswer.com/questions...idle-on-my-vw-golf-20-gt-tdi-140-bhp-54-plate

Yes there is a couple of modifications for the BKD engine referring to rough idling and misfiring under acceleration.

First one is a change to the installed software and replacement of the PD injectors.
This can only be done using VAS 5052 but also requires a change of injectors to a different part number so is going to be very expensive on a car that is out of warranty.
This mod was only done on cars with a very serious idling problem though, slight roughness at idle was deemed to be normal !?!?

Also for this engine there is another modification done, mainly to erradicate a misfire when accelerating, usually around 1000 to 1500rpm.
This is much more of a common problem and seems more to occur on engines with a slightly higher mileage.
There is a new loom for the PD injectors fitted inside the cylinder head , part number 03G 971 033 D.
To check if this has been done you will need to remove the camshaft cover and check the tag on the loom for its part number. If it has anything other than the above number it needs to be replaced as there can be a connection problem with them.
There are also quite a few checks that need to be done ideally with VCDS(Vag-Com) to determine if bubbling is present in the injectors as there are one or two faults that can crop up in relation to the fuel flow through the head casting into the injectors and injectors coming loose in the head.
Again these will also give the symtoms you describe but are somewhat rarer.
Unfortunately diagnosis of this nature would need to be entrusted to a highly experienced diagostic tech with the correct equipment or a VW Agent.
 

Joec1

Active Member
Feb 9, 2010
75
0
Wiltshire
nope... mines still buggered... the refresh of the ecu did nothing...

it slips into a limp mode at around 3k in 6th only... (around 75mph) so theres a thoght it could be fule related...
 
Hi Guys,
Had my Altea now for just under 2 months. Amazing car and would ask for anything else at the moment. Its a 2.0 TDi Sport (Manual).

When i come out on these very cold morning i put the key in the ignition, wait for the glow plug light to go out. Then i start and the car turns over instantly!

Then when i get to to work i quite frequently have to move my car after 10min to another space after the last shift have left.
When i get into the car the engine is still warm, but i follow the same procedure to start as above, but then when i make the final turn, the car can take 3-5 seconds before it will turn over.

Is this normal? i always thought the car would turn over easier when the engine is warm.

Does anyone else experience this?

Many Thanks

Chris

just adding some info.

it is a known issue on BKD engines seems to be related to Temp Sensor and or Starter motor.

friend of mine replaced glow plugs as well but finally put in a new starter motor and it fixed the issue of the warm start. it would appear either the engine does not turn over fast enough or that the old starter motor is drawing too much current.

Simon
 
Also have a very lumpy idle on my 2.0 TDI 140bhp. Dealer(s) have had several 'looks', but can't find anything wrong. Just gone out of warranty (60k+ miles - 2 1/2 years old), so will be interesting to see what a real mechanic finds at the next service!!

I added the egr gasket, it did help in the lumpy idle and seemed to improve throttle response and smoothness.

more info here:

http://www.seatcupra.net/forums/showthread.php?t=290265
 

Rob37

Guest
I had this exact same fault, when engine was hot it would take 3 or 4 seconds for the engine to fire, but cold it started fine.
Took it to one dealer told me the bkd engine did this and he didn't know what to do!

Then took it to dealer in town where I work and they had a look, he found a fix on his vagcom basically the software on the ecu needed updating, he did this and now my car hot starts 1st turn of the starter every time! I couldn't believe what a difference it made, so anyone with a bkd hot start issue I would seriously get the software checked and make sure you have latest
 

legin2009

Guest
Warm start - solution

This one was addressed a few years ago, so here is a recap...

The warm start issue is well known and the solution goes back to HAMMAN in Sept 2005. Basically the problem is due to the fact that when the engine is hot, and you crank the starter, the ECU is programmed to wait for the engine to reach a certain rpm before it starts injecting. So if your starter and battery (and connections) have a few years wear you will reach a point where you dont quite meet the rpm threshold when cranking, so the ECU just waits and holds back injecting. Once the problem starts occurring, it obviously accelerates because the starter motor and battery do much more cranking.

VAG would not (at least a few years ago) offer any ECU mapping upgrade that removed this "feature". Maybe thats changed today on newer models.

Often a new battery or moreso a new starter motor will solve the problem. HOWEVER a much cheaper solution is just to fool the ECU into thinking the engine is cold, but only when the starter motor is running. This can be done by inserting a resistor in series with the temp sensor, but only when starter is cranking. This was originally proposed with a manual pushbutton (per Hamman mod of 2005) but many of us have since implemented with a relay, where relay is driven by starter motor 12v.

My own solution was to insert a 2200 ohm resistor in series with the temp sensor (this increases the resistance seen and hence ECU thinks engine it is 30C colder). I then wired a relay to this such that the relay contacts (NC, COM) default to shorting out across the resistor. So normally the resistor has no effect. The relay activates only when the starter motor is spinning, at which point the contacts open and the 2200 ohm is no longer shorted, hence an extra 2200 ohm resistance is now seen in series with sensor. I did it this way so that it would not risk any "break-before-make" switching type glitches where ECU might be upset if it briefly saw an open circuit.

Physically, my solution consists of a tiny relay, with resistor wired across the NC,COM contacts, all heat shrink sleeve wrapped and then bolted onto the bulkhead. The relay coil is activated by 12v from starter motor live.

Mine has been working great for 3 years now, 50,000 miles. .. and since the day it was installed I have never had a single embarrasing episode of warm start cranking!!

Hope this recap helps
 
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skordys

Guest
Had same problem last year with my Altea 1.9pdtdi 2005,
temp senors replaced twice + glow plugs - no results
belive me or not but ex audi magic man replaced starter for me last year and since that is instantly start cold and warm :)

he said starter in my Altea been too weak and overheating so quick, he also said is common fault in diesel VW brand cars.

so new starter is the answer.

cheers
 
Dec 5, 2007
888
0
N W Leeds
anybody know where brushes can be obtained? This really is the only part than can wear apart from bearings needing a bit of grease and tlc.
 

rich13

Guest
Hi guys,

I placed a thread on the forum about a year or so ago regarding a poor starting problem when hot, and after extensive work with new sensors and filters etc, I read the above thread with regards to the ECU 'feature' with regards to the cranking speed when hot.

I have spoken to SEAT UK about this matter as it was mentioned that VW choose not to recognize this issue and it was not a common fault and not a issue that was raised to them until now.

I put the above issue to them today and with the customer service manager and technician in the backround, it was accepted today that the ECU on altea's (which is also commonly used across the VW) range, DOES have a feature within it that when the engine is hot, it requires a engine cranking speed between 270- 280 RPM for the speed sensor to detect the necessary engine speed for the ECU to allow the injectors to prime and inject. The apparent answer for this is that the engine need to be cranking at that speed for combustion to happen.
What they couldn't answer was that point that after 10 seconds of cranking, the ECU has a default feature that if ignition / combustion hadn't occurred by then, the ECU would allow the injectors to pump fuel, and therefore engine eventually starts.

They wouldn't comment on other questions at this time because the customer service manager then understood that it was a design / mapping oversight (the penny dropped), and stated that the car would need to go to a SEAT dealership for investigation.

The reason they are not aware of the problem is because most of us SEAT owner have issues with the cars out of the warranty period, and therefore can't afford dealer prices. So if they are not experiencing the same reported faults, then they are not seeing a problem for them to address, and therefore the fault will continue.
 

GazGT

Active Member
Jun 25, 2005
304
0
Manchester
Well I'm glad it's not just my car that's doing this. I used to stop the engine of my old car in traffic but now I don't because I never know how long I'm gonna need to crank it over to get it to fire.
 

k5roc

Rob O
Apr 17, 2008
39
0
Worcestershire
www.k5roc.co.uk
this warm start problem has been happening for a while and I did nothing about it, however the starter motor failed last night, so it could be a sign that the starter motor is on its way out

for reference we have a 2004 Altea 2.0 TDI DSG with 107,000 miles
 

neilmac

Just starting to tweak...
Jul 12, 2006
294
1
Just to add, I had a warm start issue. Car would start fine from cold. Drive it for 15 mins, stop, turn off. When turning back on was turning over but wouldn't fire with some persuasion from the throttle to increase fuel.

I've heard that the starter motor needs to crank the engine to something around 100 rpm when its warm (as the car can detect its warm) before it will fuel properly. The starters wear out and this becomes hard to achieve.

I was sceptical but replaced the starter motor (got a decent one from return from GSF) and now it starts quick as a flash cold or warm. Super quiet now as well and the car doesn't shake as much on firing.

Might help someone else....