Well I've finally managed to get my AAN boosting properly by replacing the MFTS.
The engine is standard other than an air filter cone and a one off exhaust system (runs a standard downpipe which then splits into two 2 1/2 inch pipes with one silencer each and the ECU has a chip and external 3bar MAP sensor.
I've only been making use of the boost (goes up to 22-23psi / 1.5 bar) for around a week when suddenly yesterday it would only boost to 15psi and then kangaroo like crazy. I turned off/on and the fault cleared. Plugging in with Vag-com showed that it had overboosted (00544 Maximum boost exceeded). Should I have changed a boost sensor when fitting the chipped ECU?
This morning, it started misfiring at anything over 10psi. It runs smoothly otherwise, idles smoothly, pulls well up to 10psi but 'flutters / misfires' if you try to push it above this.
I've just checked the fuel pressure and when running I have 57-58psi. Once turned off, it drops to 49-50psi. I left it for around 25-30 minutes and it didn't lose any pressure. That said, when I first disconnected the fuel pipe to fit the T-piece, there was a fair amount of air in the fuel line, not just fuel. More about this in a moment.
I've pulled the plugs out and they all look good, light grey. They're Bosch FR5DTC and have only done 2-3,000 miles.
I'm running the standard injectors, coils etc.
When checking the plugs, coils and coil tubes, I had a quick look at the wiring etc. Everything looks fine.
Any ideas as to where to start?
One other fault to work out. The engine does not want to start when hot. I know that this is a separate fault as this has been an issue ever since I installed the engine. I wonder if the fuel is getting hot enough to boil off creating a lack of fuel. It takes a good 30 seconds of cranking before the engine fires and then it won't idle. It takes a few minutes of driving before it returns to normal. I haven't had a chance to test the fuel pressure while it won't start. I think I'll need a remote fuel pressure gauge for this. Anything obvious?
Thanks in advance.
MG
The engine is standard other than an air filter cone and a one off exhaust system (runs a standard downpipe which then splits into two 2 1/2 inch pipes with one silencer each and the ECU has a chip and external 3bar MAP sensor.
I've only been making use of the boost (goes up to 22-23psi / 1.5 bar) for around a week when suddenly yesterday it would only boost to 15psi and then kangaroo like crazy. I turned off/on and the fault cleared. Plugging in with Vag-com showed that it had overboosted (00544 Maximum boost exceeded). Should I have changed a boost sensor when fitting the chipped ECU?
This morning, it started misfiring at anything over 10psi. It runs smoothly otherwise, idles smoothly, pulls well up to 10psi but 'flutters / misfires' if you try to push it above this.
I've just checked the fuel pressure and when running I have 57-58psi. Once turned off, it drops to 49-50psi. I left it for around 25-30 minutes and it didn't lose any pressure. That said, when I first disconnected the fuel pipe to fit the T-piece, there was a fair amount of air in the fuel line, not just fuel. More about this in a moment.
I've pulled the plugs out and they all look good, light grey. They're Bosch FR5DTC and have only done 2-3,000 miles.
I'm running the standard injectors, coils etc.
When checking the plugs, coils and coil tubes, I had a quick look at the wiring etc. Everything looks fine.
Any ideas as to where to start?
One other fault to work out. The engine does not want to start when hot. I know that this is a separate fault as this has been an issue ever since I installed the engine. I wonder if the fuel is getting hot enough to boil off creating a lack of fuel. It takes a good 30 seconds of cranking before the engine fires and then it won't idle. It takes a few minutes of driving before it returns to normal. I haven't had a chance to test the fuel pressure while it won't start. I think I'll need a remote fuel pressure gauge for this. Anything obvious?
Thanks in advance.
MG
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