help!! cerbera sounding like a shotgun constantly!

[gcpeters]

i dont know whats up with it now, but i thought id post and see what you guys have to say

the cerbera starts of running ok, infact running really well! then about 20 mins or so it runs like a complete dog, its popping and banging all the time constantly out the back and feels as if its not fireing on all cylinders, then suddnely it will clear itself and take of at a 1000mph and then do it will do the same again

even if i have it just idling it will be runnning really really down on power like foot half down and going no where and it will be popping away, bang bang bang and flames and crap out the rear pipes!!

the MIL light doesnt come on at all,

so any ideas??? my wallet is feeling very very nervous

[pvapour]

My guess would be Something electrical getting hot, breaking down & causing unburnt fuel to pass through the system = big bangs (not good for cats if you have them still) maybe HT leads etc,

when you say it stops for a while and then comes back, is this once you've got up some speed and got some air flow through the engine bay? hence cooling things a bit......

not a mechanic so just a wild guess, hope u sort it.

[simonsparrow]

Sounds similar to when my oxygen sensor failed, but as you say, no MIL light.

Bad fuel maybe, has it been standing a while?

[spartacus]

gcpeters said:

i dont know whats up with it now, but i thought id post and see what you guys have to say the cerbera starts of running ok, infact running really well! then about 20 mins or so it runs like a complete dog, its popping and banging all the time constantly out the back and feels as if its not fireing on all cylinders, then suddnely it will clear itself and take of at a 1000mph and then do it will do the same again even if i have it just idling it will be runnning really really down on power like foot half down and going no where and it will be popping away, bang bang bang and flames and crap out the rear pipes!! the MIL light doesnt come on at all, so any ideas??? my wallet is feeling very very nervous

Having exactly the same problem myself, particularly if run for hour or so then park up for a while, on return journey starts to misbehave as you describe, it really feels like leads breaking down to me, the power loss and intermittent nature of it. Just 12k service and dealer swears the fitted new leads, could be duff set I suppose.

[davetherave1970]

gcpeters said:

the cerbera starts of running ok, infact running really well! then about 20 mins or so it runs like a complete dog,

If it's OK when first started my guess would be the ECU coolant sensor had failed. Engine could be fueling for cold running when hot. Just a guess really but if I'm correct shouldn't cost much!!
Hope you get it sorted!

[danfrith]

Hi had all the same problems as you! in the end it was 4 bad leads! and driver side lamber senor completely shot! i would say it is this!

get some one to plug a laptop into it, you will soon find out!

cheers

Dan

[nervous]

gcpeters said:

i thought id post and see what you guys have to say I'm feeling nervous

wouldn't be so bad, but he doesn't even cuddle me after-wards.


sounds like an ht lead shorting out to me. pull em, i bet you'll find you've one with a trace on it. good old electrical insulation tape will do you proud until a kidney can be sold on ebay to raise the funds for a juicy set of magnecor leads

[spartacus]

nervous said:

gcpeters said: i thought id post and see what you guys have to say I'm feeling nervous wouldn't be so bad, but he doesn't even cuddle me after-wards. sounds like an ht lead shorting out to me. pull em, i bet you'll find you've one with a trace on it. good old electrical insulation tape will do you proud until a kidney can be sold on ebay to raise the funds for a juicy set of magnecor leads

I'm having the same problem, can you explain what you mean by a trace, do you mean shorting through burnt insulation? I don't suppose there is any way of testing leads individually apart from a visual inspection?

[danfrith]

you can test the leads with a volt meter, to see the kind of ohms it is allowing through.

but you then have to take the leads off one at a time!

[nervous]

there will be a track of carbon where the lead is shorting from. be advised though, that its often very slight and is easily missed, especially if the leads are dirty looking already. a proper electrical test with a meter would be much more accurate obviously

>> Edited by nervous on Monday 15th August 12:55

[spartacus]

Thanks guys.

[BCA]

Sounds like the "other" map in the ECU has come into play. Ours did this when the battery was disconnected for a while.

Im not sure why it did this, but the fix was a few 0-top of third gear runs. It realised after a couple of runs that it needed to be in a more happy map and started to play along again. The next few runs afterwards (was a while ago) was done to make sure it was running fine... and err, because it was fun. LOVE THAT CAR!!!!!!