TDIT

Hi all!

I hope I have placed this in the correct section - my apologies if not (admin please let me know if I goofed.)

Guys and Girls, I have a problem!

I have a 13B Series 4 Turbo which has been a very reliable car. It's boost is fairly low (10) and I'm happy with that as it still brakes traction in 3rd with 205 rubber. However, things are no longer good and I'm hoping someone out there can point me in the right direction.


The problem:

When the car warms up it starts to fail through (what seems like) fuel starvation. What I mean by that is this: Idle is fine. Gentle load is also fine. Full throttle and boost response is also fine - even if I stop at 3 or 4 thousand rpm. IE: everything is perfect, until... Until it warms up more and more, then it all starts. First I plant my foot and I get 'perfect' response for a second, then total lost of power, then an immediate return to full power (the wip-lash is a killer) until it looses all again etc etc. If I back right off (to say 10% throttle only) I have the same problem problem. The more it warms up the greater the issue becomes. It gets so bad that full throttle delivers almost zero power, but 5% throttle gives the ability to limp somewhere in second gear at around 15 miles an hour. If I try for more, it does and threatens to stall completely.


Things I've checked:

I've replaced the fuel filter and tested flow at the engine bay while cranking it over (I also checked it for water in the fuel + added metho just in case). The flow was very good both before and after the filter was replaced. I also tested the fuel return flow and seemed normal (compared to a mates series 4 RX.)

I've also replaced the plugs and fuel regulator - there was zero difference.

I've also checked for ignition spark both cold and at running temprature via a timing light and dwell meter. All rate the same and the spark appears good on all 4.


Recent history:

The exhaust manifold had a crack in it so the car developed no boost when it warmed up (and the crack opened). I had that repaired a week ago, and although I am definaitely not rulling out a bad repair as the cause, I don't know how a bad repair could cause this problem. I mean, it it's still leaking I wouldn't have any boost right? But I have boost when warming up and when hot - UNTIL it looses power again.

Also, the day before this started to happen I was caught miles from anywhere and almost out of fuel. By the time I found a gas station the car had already started to cough. I filled up completely and continued on my way.


Where I'm looking next:

I'm thinking of removing the inlet manifold and see if there's a gasket leak that's opening up when it heats up. or maybe the exhaust repair was bodged and they damaged the gasket upon reassembly. I really am not sure at this point and open to suggestions.

Sincerely, I don't mind being told I forgot something obvious. I really need the car running and have a limited budget, so any suggestion will be appreciated.

Thanks in advance!

TDIT

Hi all,

Very proud to say I fixed my problem. However equally embarrassed as to the cause. You know what they say - it's all about timing! In a nutshell the timing was very advanced. One of the first things I should have checked? Maybe. But at least it was found fairly quickly.