help!!! glowing precat

Matt

hey

ive been working on a astra coupe 51 . it had a rattle which turned out to be 2 of the roller lifters had jumped out and the tensioner blade bolt had snap so there fixed now and its retimed .the next problem ive found is its running terrible and the precat is glowing after probley 3minutes running maximum of varied engines speeds nomore than 3thousand tho .
when running the engine it filled my unit with loads of moisture and an awful eggy smell .also the ecu light came on and went in to limp mode wouldnt let me rev it past 3thousand i think ? only tryed it once till i noticed cat

any ideas people? im totaly fed up with this car nothing but problems notsure.gif

thankya phil

JohnnyN

Bloody hell! Usually when there's an eggy smell, that's the cat gone especially with the management light on. Is the timing definately correct?

Matt

im 95% sure its right yes i allways seem to have to turn it over loads and loads after timing it for the marks to realign is this normal ? ive undone the bolts on the maifold and pulled the exhaust accross and there is still a cat in there looks like any normal one no dammage that i can see unless internal .

was hoping this was just a collapsed cat but got a feeling it not going to be

phil

JohnnyN

Where's Vocky?

dunno..

vocky

doesn't sound good, the heat could be caused by over fuelling, the upper lambda could be duff, but as the rockers had broken I suspect it has bent valves and the fuel is leaving the cylinder and burning at the precat instead.

so it's worth doing a compression test to ensure the cylinders have a minimum of 12 Bar and a maximum of 15 Bar

Matt

ive done a compression test they where all around 13-14 bar . the rockers dint break they just came out for some reason??? . there not dammaged in anyway altho i have replaced the 2 lifters . so confused about this now . ive never had any troubles with cats so dont know what happens if they collapse or if they do collapse i dont know

philip1

I would check the timing again I've done this a time or two and went mad thinking something had gone horribly wrong. I found I had missed by one tooth and that melted the cat so check your timing again it could be just that simple.

JohnnyN

Get the precat out anyway, you don't need it and it'll give you a little more power and torque.

;-)

Matt

im going to tomorow nothing more i can think of and you guys dont know whats goining on so something is wrong somewhere

philip1 said:
I would check the timing again I've done this a time or two and went mad thinking something had gone horribly wrong. I found I had missed by one tooth and that melted the cat so check your timing again it could be just that simple.

what happens with the lambas then if i was to remove the precat does it all work ok ? this ones not mine so dont wana send it back with a light on . oh and does it affect mot in anway ?

JohnnyN said:
Get the precat out anyway, you don't need it and it'll give you a little more power and torque.

;-)

let ya know how i get on tomoz hopefully ive made a woopsie lol

phil

JohnnyN

Removing the precat will not affect the MOT. The sensors stay and everything is fine. The precat is only there to help remove the harmful gases on startup before the main cat gets upto temp. I think the newer Astras 2003 onwards didn't have precats anyway.

They're a right bastard to get out. You will need a damn good drill and cold chisel.