No brakes, running on 3cylinders, EPC and TC light on

[akz]

Hope some1 on here can help me. I have a 52 plate octavia vrs and its constantly playing up. Its only running on 3cylinders and the brakes are barely working! And when this is happening the EPC light and Traction control light are on.

I've read on here that it could be the brake pedal switch. But does anyone if thats defo it?

[Tech1e]

You will have reduced brakes due to no vacuum assistance when it's missfiring, sounds like a coil pack.

[Interphase]

I've had cases of a constant but driveable misfire when the throttle body failed to run a basic setting properly, and that lights up both of those warnings too. Try turning the key to position one and leaving it for 30 seconds, then starting it, see if it clears the misfire temporarily. If not, kill it straight away in case it is a coilpack as you don't want more damage.

[akz]

Does the coil pack not throw up the engine management light tho? And it wouldn't effect the brakes would it?

Interphase how did u fix yours? Turning the key before I turned it on for 30seconds as temporarily fixed it

Edited 15 January, 2011 by akz

[Interphase]

Depends on why it's broken tbh. The 30 seconds thing allows the ECU to run a basic setting on the throttle body, which you'll hear as a series of whirrs and clicks with the bonnet open The problem I had was a weird one that's affected a fair few people but there's never been a reliable solution. I had a flash of inspiration the other week that I'm currently trying to work out how to test, so if that pays off I'll put the info around.

Best bet is to get someone to scan it for codes as soon as possible before replacing things - if it throws up codes relative to the throttle body then a damn good clean is a good starting point. You'll probably see misfires across most of the cylinders too if that's the case. If it's not that, then what you see should pinpoint the cylinder at fault in the event that a coil pack has gone.

[Tech1e]

Has the brake pedal gone hard?

[akz]

Aye the brake pedal does go hard.of its missing on most cyclinders which a think it is, then a think its the throttle body. Also i have just recebnly repcaed a coil pack and before i did it it was running a differentkind of lumpy?

[Tech1e]

As I have said previously the pedal will go hard if there is a missfire as there wont be any or very little manifold vacuum to power the servo. Or the other possibility is one of the vacuum lines has split thus causing an air leak, rough running and a lack of assistance.