Got 8 fault codes on newly built engine, help please.

**Rusty** · 10 May 2015, 19:06

Have you done up the ECU earths to the engine correctly?

N80 may be unplugged...

Other than that, to have that many issues, I'd say it's electrical earth or similar.

**k.alle** · 11 May 2015, 08:20

I think so. ECU takes its earth from inlet manifold right?
As I said, the IM is painted and I suspected it to have bad earth due to this fact and therefor the extra earth wire from the ABS unit.

N80 is the blue one behind the head right?
It is connected and clicked when I did the output test.

Is there an earth point I have missed somewhere?
Big one to engine block, coil earth to cam cover, and ECU to IM.

The car ran fine prior to the engine swap.

**Rusty** · 11 May 2015, 09:25

If the engine isn't earthed to the chassis, then that could be your problem. Remove all paint and dirt, do it up nice and snug and then cover in grease to sgtop corrosion.

The N80 is indeed the blue one behind the engine. It needs to stay electrically connected even if it's redundant. AFAIK.

**k.alle** · 11 May 2015, 16:49

OK, so I need to look at the main earth (chassis -> engine block) and see if that can give me any clues.
Alright, then the N80 is in fact present and connected.

Does the injector harness run in to a connector somewhere that I could have upset?

**k.alle** · 15 May 2015, 16:49

If anyone has more input to give I happily take it.

I'll be going to the car tomorrow and will try to solve some of these, as I have 100 km to the car I like to have as much as possible to look for while I'm there.

To Do list so far.
Inspect earth chassis to engine.
Inspect fuses.

Fault codes in clear text:

01247 - Activated Charcoal Filter (EVAP) System Solenoid Valve 1 (N80)
31-10 - Open or Short to Ground - Intermittent

00553 - Mass Air Flow Sensor (G70)
07-10 - Signal too Low - Intermittent

00540 - Knock Sensor #2, G66
03-10 - No change in signal (?) - Intermittent

01262 - Wastegate frequency valve, N75
31-10 - Short to ground (?)- Intermittent

01250 - Fuel Injector for Cylinder 2 (N31)
31-10 - Open or Short to Ground - Intermittent
01251 - Fuel Injector for Cylinder 3 (N32)
31-10 - Open or Short to Ground - Intermittent
01252 - Fuel Injector for Cylinder 4 (N33)
31-10 - Open or Short to Ground - Intermittent
01252 - Fuel Injector for Cylinder 5 (N83)
31-10 - Open or Short to Ground - Intermittent

These share the same fuse S24 and each of them give Limp-Home Mode:
Wastegate frequency valve
Idle stabiliser valve
Carbon canister solenoid valve

These share the same fuse S28 and the engine should not run if it is shot:
Fuel Injectors & Air Mass Sensor

That is all that I have been able to dig up on my own.

**220bhp** · 16 May 2015, 07:10

Did you pull any of the connectors of at any point with the engine running. If not it has to be an earth problem. Are you sure these codes prier to fitting the engine.

**k.alle** · 16 May 2015, 07:18

Yes, I did pull the injector connectors in my pursuit to localize the rough running.
However, I did clear the codes and they returned immediatly.

I will try to pull the ECU fuses and see if they still comeback.

I didn't pull the codes with old engine, but it idled and revved as smooth as always. I just warmed it up and moved it within the garage.
Prior to that it has been parked there for 1 & 1/2 year.

**k.alle** · 16 May 2015, 12:29

OK, I am in the car now with my laptop.

I pulled ECU fuses and that seemed to take care of the fault codes.
The idle is till trying to shake the whole car to pieces

Have had Injector #4 come up a couple of times since, it seems intermittent since I can have the car on idle for ~5-10 min without it coming back.
Gonna have a look at that connector.

I took a couple of screenshots of the measuring blocks at idle.
Thing is I have big issues accessing the ECU when the car is running, so these are snapshots from within 4-7 'ish seconds of idling.
After that Vag-com flips out with error messages, can't sync and what not.

Is there anything in these pictures that seems off?

Attached Files

**k.alle** · 16 May 2015, 13:55

I've been under the car and measured resistance (ohm) between the earth strap mounting bolt on the block and right hand side engine mount nut.
0.02 ohm which means good ground right?

Right hand side engine mount bolts is welded to chassis if my thinking is right so that should mean that it is good connection, or am I barking up the wrong tree here?

[EDIT]
Have now made an ohm measurement from mounting point of airbox (m8 thread) to back of the head.
Result 0.00-0.01 ohm.

Need to find out best practice to measure injector harness.

**Error404** · 16 May 2015, 14:22

What codes now you have cleared those stored faults you posted above? What ignition set-up are you running?

**k.alle** · 16 May 2015, 14:30

Just had it idling a bit and no fault codes ATM.

Ignition setup is standard ABY with NGK BCPR7ES plugs.

[EDIT]
Plugs are gapped to 0.5 mm.

I have 14v from S24 to both IM earth points.

I have tried with two spare POS now and it made no difference.
I think i should take it out for a spin and see how it behaves under boost now that i dont have any fault codes.
Could give some clues to if this is a strictly idle issue.

**k.alle** · 16 May 2015, 16:33

I've just come back from my test drive.
Engine pulled nicely to 1.3 bar or something.
Went through the revs with ease, that SM flywheel definately makes a difference!
Not at all like the first time I had it out.
Got this a couple of times which brought me back to spring boost:

00540 Knock sensor #2
No signal

Both knock sensors are new...

One thing though, as I was out I noticed the charge light (red battery symbol) starting to come on.
Voltmeter showed 12V and then went back to 14V and finally to 12V and started to descend to <8V.
When I rolled into the garage the car died, completely out.

Could this be a battery issue?
It has been uncharged for 1.5 years.
Generator has a new charging relay.

To summarize:
Car went fine when on boost.
Got knock sensor 2 code.
Voltage dropped to the point that the car died (nervous last KM's)

I seem to have an idle issue + knock sensor acting up and voltage issue.

My post is a mess I know but I am truly grateful for all input.

**k.alle** · 16 May 2015, 18:59

Red battery check light is not lighting up with ignition on, I removed the bulb and it lights up with 12V feed.

I've measured the ohm between D+ ring terminal (removed) and generator chassis.
I get some mega ohms, if I understand this correctly this points to the regulator.
The regulator is new, will have to check if it has come loose.

Ohm between generator chassis and engine is 00.2 ohm so it seems grounded.

This thread started with fault codes and has evolved to generator fault and knock sensor issue. LOL [emoji14]

**k.alle** · 17 May 2015, 11:49

Found the problem with generator.
One of the brushes had got stuck, freed it and battery light bulb has come alive again.

Still rough running on idle.
I'm running ADU camshafts and ADU sprocket, could this cause rough idling?

Had a look on the Knock Sensor #2 connector, no corrosion visible.
Not sure what to look at next?

Got 8 fault codes on newly built engine, help please.

Got 8 fault codes on newly built engine, help please.

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