Forge rebuild after blown engine - 1 single spark when cranking

M

muppy

Greenie N00B Member
Greenie Member
So I've recently had my MK1 3 rebuilt and forged after ZZB flat foot shifting
We're having issues getting it to fire after everything has been put back into the chassis

What issue we're currently having is that the engine cranks, but only produces 1 spark across the cylinders and that's all

Everything is grounded, all sensors have been changed and the timing is correct, fuel pressure and anything we can think of has been checked over

We changed the loom, coil packs and even ecu!

I would massively appreciate anybody who understands or who has had the same issue rectified to shed some light

Thanks in advance!
 
1 spark basically in firing order 1 time, then nothing?
 
Do a data log and see if pops up something. Any CEL codes?
 
Raider said:
Do a data log and see if pops up something. Any CEL codes?
Click to expand...

Getting a fuel pressure regulator code (P0089) when scanning with obd alongside an ABS code but it seems like it's just giving us random codes tbh

Will try to get a log while cranking
 
muppy said:
So I've recently had my MK1 3 rebuilt and forged after ZZB flat foot shifting
We're having issues getting it to fire after everything has been put back into the chassis

What issue we're currently having is that the engine cranks, but only produces 1 spark across the cylinders and that's all

Everything is grounded, all sensors have been changed and the timing is correct, fuel pressure and anything we can think of has been checked over

We changed the loom, coil packs and even ecu!

I would massively appreciate anybody who understands or who has had the same issue rectified to shed some light

Thanks in advance!
Click to expand...

When you changed the ECU, did you get it re-flashed for your vehicle or just plug it in?

When you checked fuel pressure what did you see?

If the spark plugs are consistently firing in order and only 1 time after every ignition cycle, then that sounds like an ECU failsafe.

Why do you think the ECU is giving you random codes? This is normally the best source of information for figuring out your problem.
 
The_big_dill said:
When you changed the ECU, did you get it re-flashed for your vehicle or just plug it in?

When you checked fuel pressure what did you see?

If the spark plugs are consistently firing in order and only 1 time after every ignition cycle, then that sounds like an ECU failsafe.

Why do you think the ECU is giving you random codes? This is normally the best source of information for figuring out your problem.
Click to expand...

Changed the ECU along with clocks, ignition barrel and key from a donor car

And I feel like they're random mainly because we have checked over any codes it's given us and all seems fine
 
muppy said:
Changed the ECU along with clocks, ignition barrel and key from a donor car

And I feel like they're random mainly because we have checked over any codes it's given us and all seems fine
Click to expand...
My recommendation:

Revert to the original ECU, barrel and key.
Gather data from your car: codes, fuel pressure etc.
Do some research or post your findings here.

We will support you with knowledge of common problem areas - the ECU is rarely a problem.

There is the possibility that codes could be misleading, but unless you have evidence to show why the ECU is wrong, then I would focus on what the code is hinting at. You can then use the service manual or ask for help, but we need more information.

Here is what the manual says about P0089: "If the fuel pressure average value measured by the PCM exceeds the specification when the camshaft is rotating at a specified rate, the PCM determines that there is a fuel pressure regulator performance problem."

The diagnostic procedures tell you to check the HPFP connector and spill valve. These can be better diagnosed with fuel pressure behavior.

The ECU may be disabling your ignition to protect the engine since it found a problem with the fuel pressure - This is what I meant by a "Failsafe".
 
Recently just checked over timing (found that the 8mm bolt was still in the crank shaft pulley while cranking and it threaded itself out)
Changed fuel pump including spill valve
Did a compression test and we get a nice 180 across all 4

Did a scan for codes, still nothing.

Running out of things to check, hoping it's not the wiring inside the car but I don't really see how that could have gone wrong since it was fine before it blew
 
muppy said:
Recently just checked over timing (found that the 8mm bolt was still in the crank shaft pulley while cranking and it threaded itself out)
Click to expand...
How did you check timing? How confident are you that the bolt in the pulley did not interfere with anything behind the pulley?

Have you reverted to the original electronics?
 
The_big_dill said:
How did you check timing? How confident are you that the bolt in the pulley did not interfere with anything behind the pulley?

Have you reverted to the original electronics?
Click to expand...

Confident that it’s timed correctly, unsure if the bolt mistake interfered with anything behind the pulley what could it interfere with?

Reverted back to original electronics besides engine loom, also took WOT box out
 
it sounds like a immobizer issue. the immobilizer info is stored in the gauge cluster. is there a flashing key symbol. a immobilizer issue won't show a code. you wont get fuel or ignition. the key cluster is mated. crank/cam sensor would throw a code. or you have a hole in your loom.
 
5doorsoffury said:
it sounds like a immobizer issue. the immobilizer info is stored in the gauge cluster. is there a flashing key symbol. a immobilizer issue won't show a code. you wont get fuel or ignition. the key cluster is mated. crank/cam sensor would throw a code. or you have a hole in your loom.
Click to expand...

It's not immobiliser, what do you mean by a hole in my loom? We replaced and inspected the loom and it looked fine
 
Did you correctly set the CPS?

- Make sure Cyl 1 is at TDC (if you did the timing right, the hole on the crank pulley should line up with the hole on the timing cover)
- Count counter clockwise the 20th tooth from the blank space on the crank pulley
- line up the sensor with the 20th tooth.
 
KiwiFlavor said:
Did you correctly set the CPS?

- Make sure Cyl 1 is at TDC (if you did the timing right, the hole on the crank pulley should line up with the hole on the timing cover)
- Count counter clockwise the 20th tooth from the blank space on the crank pulley
- line up the sensor with the 20th tooth.
Click to expand...

Yeah it's lined up dude, thank you though
 
I'm trying to get a log while cranking but I'm having trouble making sense of the .log file I've obtained from my AP

Just a load of Japanese looking characters, been trying to find a way to read it but it's titled ERROR_1 so I'm unsure if I'm even able to lol

I've uploaded it here: https://easyupload.io/bqx8mp

In case anybody knows how to read it
 
muppy said:
I'm trying to get a log while cranking but I'm having trouble making sense of the .log file I've obtained from my AP

Just a load of Japanese looking characters, been trying to find a way to read it but it's titled ERROR_1 so I'm unsure if I'm even able to lol

I've uploaded it here: https://easyupload.io/bqx8mp

In case anybody knows how to read it
Click to expand...
you know you can just upload directly to the forum via attach file right? pics and files that the best way to do it.
 
If I recall, ECU swap takes dealer reprogramming to work. Also, the cluster is also needing to be swapped too.

It's a revert to the original ECU and key and try again. If it's not working because original ECU is trash, it's probably needing to get paired together.
 
Raider said:
If I recall, ECU swap takes dealer reprogramming to work. Also, the cluster is also needing to be swapped too.

It's a revert to the original ECU and key and try again. If it's not working because original ECU is trash, it's probably needing to get paired together.
Click to expand...

Yeah, we're back on the original ECU. I'm pretty sure the ECU is fine, I'm just trying to gather possibilities why it gives spark but doesn't start. Since the engine blew, could the fuel pump shut off be activated and cause it not to start after rebuilding?

Maybe I'm over thinking

Actually, fuel pressure is fine so I'm not sure if that could even be the case
 
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