BFB cabrio start probleem

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He members i'm new here and could realy need some help with my cabrio that needs to be in good condition 9th of may for the dyno.

The start probleem whas there before the next repairs.
BFB 20VT 1.8T

- reconditioned OEM cilinder head, (new valve ext)
- new timing chain
- new timing belt (with al that comes with that)
- new drop in bar tec Fuel pump
- new crank position sensor
- new water temp sensor
- new fuel filter ( not OEM ! Can that be a problem?)
- new Lambda / O2 Bosch is on its way.

What is the problem exactly ?:
The car starts fine but the engine wont go on.
IF it starts the first time you have to crank a long time.
If you interrupt the first crank and go for second you have a much higher chance the engine exactly fires up.

Yes i am a mechanic, and if you ask me it feels like a Fuel pressure problem.
IF so how is the fuel pressure regulator on my car ?

Or do some of you have some other idea's.
Thank you

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Sorry trying to improve my English, but unable to change my previous post.
My apologies

[EuroxS4]

Check mechanical timing of both cams and timing belt as well. Not trying to be a dick but if your a mechanic then I would assume you have some readings and tests you performed? Compression? cylinder leak down? Fuel pressure test? hot soak test? and so on. Verfieid you have good spark? plugs are correctly gapped? Timing is correct and verified? You have good fuel supply?

[SideMirror]

If you're not able to read the codes to help identify issues. I would start by rechecking engine timing is correct, fuel pressure is 4 bars at fuel rail, MAF is clean and MAF sensor is good. Also recheck vacuum lines for leaks.

An issue I had when changing the fuel filter. Was the plastic lines were bent out of round restricting the flow of fuel.

Sent from my Pixel 7 using Audizine Forum mobile app

[Puddin Tane]

how is the fuel pressure regulator on my car ?

Before you modified the fuel system, did the car originally have FOUR hoses connected to the fuel filter? If so, the car's fuel reg was actually inside that filter and a sub-component of the filter and there's no provision for a regulator anywhere else in the system, so...

- new fuel filter ( not OEM ! Can that be a problem?)

YES. If your modded fuel system still uses a four-hose filter then OEM is best-- assuming that aftermarket out-of-spec pump doesn't make a hash of things.

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@euroxS4. Txn for your reply.
I'm a truck mechanic.
Yes timing is correct
Vagcom detects no misfiring.
The clearance of the sparkplugs is correct.
The only fault codes in ECU are secundaire airpump.
And cat remove related fault.
Those will be removed the 9th when car gets new software.
And should not effect engine start.

If car runs it has the power and torque you expect of a stock engine wit DSMIC an full exhaust.

Its only the start, the longer it stands still the worse it gets.

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Tnx for replying.
I see no fuel pressure regulator at the rail.
Does MAF effect engine start ?

[KEEP_ON_MODIFYI]

Before you modified the fuel system, did the car originally have FOUR hoses connected to the fuel filter? If so, the car's fuel reg was actually inside that filter and a sub-component of the filter and there's no provision for a regulator anywhere else in the system, so...

YES. If your modded fuel system still uses a four-hose filter then OEM is best-- assuming that aftermarket out-of-spec pump doesn't make a hash of things.

Yes i have 4 fuel lines in the filter.
Its still there but i placed a aftermarket new one.
My fuel system is still OEM because the upgrade pump is a drop in replacement.
I made sure to replace the fuel line from pump to the outside of the "module" as well to make sure the are no leaks afterwards.

Do you got the OEM part number of the fuel filter ?
For me it feels like the pressure regulator in the filter does not work as it should.

[EuroxS4]

To me it sounds like possibly the lines at the filter are swapped. Regulator is in the filter. I have seen that fail or injectors leak. On cold start ecm uses o2 and maf readings for fuel trims. You can try to unplug the maf and see what it does or look at mvb 32 with vcds and post those results.

[Cybersombosis]

What is your fuel pressure at the rail when cranking?

[KEEP_ON_MODIFYI]

To me it sounds like possibly the lines at the filter are swapped. Regulator is in the filter. I have seen that fail or injectors leak. On cold start ecm uses o2 and maf readings for fuel trims. You can try to unplug the maf and see what it does or look at mvb 32 with vcds and post those results.

Tnx for helping.
I will check the filter again.( Arrow from tank to engine)

Yes my o2 sensor is malfunctioning, new bosch is on its way to me.
I wil check MAF, and come back here.
And see if i can test my injectors before the 9th

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At the moment i have no execs to a gauge with the right connector to the fuel rail

[Puddin Tane]

Do you got the OEM part number of the fuel filter ?

I have grown reluctant to accommodate "part # moochers," but okay...
8E0 201 511J
This number is for my 2005 AMB 1.8t fuel system, so no guarantees. You need to confirm fitment yourself.
These filters were made for Audi by both Hengst and Kayser, who also sell them directly (same quality, less money).

You need to make sure the flow arrow points the right way, yes, but each end of the filter also has SUPPLY and RETURN ports that have to be plumbed correctly. In other words there are eight different ways this filter can be plumbed but only one of them is correct.

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Realy appreciate your help.

You fuel filter nr 8E0 201 511J.
I checked online what filter mine was compatible to the site came with the following OEM nr's
8E0201511C
8E0201511G
8E0201511J
8E0201511L

Can some one here confirm that that is the right filter for WAUZZZ8H14K027680 car ?

Really try to get the most of your advice.
1st i contacted a other garage to ask if they got a fuel pressure gauge/ connection to the rail.
He told me he will let me know tomorrow.

2nd i contacted the seller of my o2 sensor if he can give me a track and trace nr.
After installation i wil try to make a log of measur block 032 and post it.

3th i called today to a bosch test center if they can test patrol injectors as well.
Did not pick up the phone, call again tomorrow

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Just spoke to some one @ dealership that was willingly to give me the right OEM number.
8E0201511L filter should be compatible IF mounted correctly.
Wil double check that.

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@euroxS4.

After your comment on engine timing.
Yes all te marks were in place.
Did not kwow about "the 16 rollers"
This evening check engine timing

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Engine timing checked.
All good there 16 rollers, and all marks

[SideMirror]

You probably got this information but just in case you don't. Is it 16 roller with camshaft in phase with each other per marks in picture. Attachment 303866

Sent from my Pixel 7 using Audizine Forum mobile app

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Tnx for your info.
Yes that's how i count it.

I found out that the malfunction o2 sensor /inaccurate is not used for cold start.
Yes it wi be replaced but it is not my problem.

A friend send me this link.
https://youtu.be/FERyREwNi94

Looks a lot like my problem,so got the number from my MAF sensor.
Will order one tomorrow.....

[EuroxS4]

Checking MVB 32 would to told you whether you have a bad maf or not. Some people like to load the parts cannon others like to diagnose the issue. Good luck.

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Cant wait any longer on the o2 sensor still did not came in.(all dealership are closed tomorrow)
Ordered one at the local dealer.
Can pick it up at 15u, than pick up the MAF directly after.

Yes i like diagnostics but i i fight time as wel.
9th dyno 11th i leave for holiday in the car.
Later this month car has to be 100% for a meeting

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https://youtu.be/lbNElym4-LM

Nop, still the same.
Any idea's ?

Yes temperature reading with Vagcom is the same as on the combi cluster

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Engine light is cat remove and secundair airpump removed.
Nothing els, supposed to be on.

Is there a scheme of the fuel filter positions ?

[EuroxS4]

Keep throwing parts at it. How about a cam position sensor? How about a crank sensor. Take your pick. Keep guessing instead of diagnosing. Video clearly shows only 200 cranking rpms. Which is too slow should be seeing at least 400.


filter.jpeg

[Puddin Tane]

Typically when doing a filter change you're removing the old and installing identical new all in one go so your memory of hose assignments is crystal clear. If you lose track it gets messy. I THINK that's what you're asking about Disconnect both hoses coming from the pump and watch which one shoots gas when a helper momentarily turns the key to ON. That hose goes to the center port on the filter. The other hose from the pump (the return) goes to the side port. The engine side of the filter is harder to investigate. I would find out where those straight runs of hose go by referring to fuel system schematics here, identify the return hose, disconnect it at the far end and connect that end to low pressure compressed air. Whichever hose blows air at the filter, that hose attaches to the side port on the filter, the other hose goes to the center port.

[KEEP_ON_MODIFYI]

How about a cam position sensor? How about a crank sensor. Video clearly shows only 200 cranking rpms. Which is too slow should be seeing at least 400.


filter.jpeg

Tnx for you analysis.
As said the crank sensor is new.
No mail functions with regard to timing problems.

Tnx for the RPM thought, battery is A brand 2 years old.
Will test it, i know its not the wiring ( attached it my self)
Wil take a father look in to things there.

[KEEP_ON_MODIFYI]

. I THINK that's what you're asking about Disconnect both hoses coming from the pump and watch which one shoots gas when a helper momentarily turns the key to ON. That hose goes to the center port on the filter. The other hose from the pump (the return) goes to the side port. The engine side of the filter is harder to investigate. I would find out where those straight runs of hose go by referring to fuel system schematics here, identify the return hose, disconnect it at the far end and connect that end to low pressure compressed air. Whichever hose blows air at the filter, that hose attaches to the side port on the filter, the other hose goes to the center port.

Great tnx
Will check that as a last thing.
Ofcourse i think i changed it correctly.
But i'm not here, afraid to emit i did something wrong.
Try to locate the problem.
- in the time i got.
- with the tools i do have.
- and by asking you polide to share your thoughts.

I'm a diesel mechanic
My field of expertise is slightly different.
Appreciate your help.
Will post results Tuesday, even IF this problem effects final performance.

[EuroxS4]

Did you check cam position sensor as I mentioned numerous times?

[TobiqueSlang]

Just to confuse things little more, but couldn't a bad N80 account for some of this if it were stuck closed? or a cracked suction jet pump?

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First run on the dyno the car made 165hp
But i knew the start probleem would come after me.
Than fist run on other software and we had a problem making power at top end beyond 177hp.

I asked for a fuel pressure gauge, remember did not have access to one before.
And there was the problem, pressure was not consistent.
We checked the connections (thanks for the picture)
And it whas all good.
Than we checked the lines to the pump module.
All good.
I told johan (tuner) the fuel pump was 100%.
No need to check.
So it could only be the new mahle filter.
He sad, he never seen that before and was a bit sceptic.
I asked for a car and went te get a new filter in a nearby shop.
Placed it, problem solved.
Now the car runs fine and starts really well.

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It did 188hp and 297nm.

Restrictions were the bad E10 fuel we got here.
It will do 200hp on E5.
And the DSMI is a nice stock mod.........but it does not help the car a lot.
FMIC is the only thing that works probably.

But for me as a daily car its fine.
I leave it as it is performs wise.
The car does not drive underpowered at all.

If i want intercooler and hi boost i go work on my other car, that's for hobby

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[img\]https://ibb.co/ZKFmrzX[img]

[EuroxS4]

Glad you got it sorted out,but if going after big power probably better to go to rising rate fpr and ditch the stock fuel filter. IIRC stock filer has FPR built in. Most go to a 3.0 filter and go to a fuel system with return line.