idle problem after welding ??

[bigdek]

Did a few bits of welding on my sports rear arches at the weekend and now it doesn't idle very well and stalls at junctions.

all was fine until i welded it now it idles at 500 and is lumpy.

drives fine otherwise.

i used a mig welder,

battery and ecu were disconnected.

tried changing icv this morning but its just the same.

Any ideas if the welding could have caused any probs or is it just a coincedence.

What else can i try to sort the problem ?

[FLO]

As long as you disconected the battery the car should be fine. Just a coincidence.

[pacerpete]

Common occurrence once battery has been disconnected, give the car a good long thrash and it will 'relearn' and every thing will be o.k.
It only seems to happen on 325s .

[E30BeemerLad]

lol Pete, are you and a torch usually in close proximity when E30's are concerned?

[bigdek]

well thats been a few days of driving and its still sh!t

any ideas where to look.

idles too low and bit lumpy at low speeds .

Fine if you are booting it

[bigdek]

this is now pissing me off.

this morning i changed the following parts one at a time with known good parts,

blue temp sensor, throttle position switch, dist cap and rotor, afm


what else couldcit fookin be ??

[E30BeemerLad]

well it could be non-connected that the car misbehaved after the welding and therefore worth checking for air leaks, such as split bellow, any lose plumbing in the inlet system and vacum hoses and also spray carb cleaner or WD40 around the inlet manifold where it bolts to the head with the car running, if normal idle is restored briefly then it has sealed the leak.

just a cheap suggestion.

[touring170]

m8 u gotta let it idle for about 10 to 20 mins for the ecu to relearn the base idle settings .thrashing it wont do nothing exept use yor juice try it ?

[bigdek]

tried that m8.

let it idle for 25 mins took it for a drive

let it idle again.

left it for an hour

then restarted it and no change

[bigdek]

E30BeemerLad

Had another look this afternoon and sprayed carb clear on the inlet manifold gaskets.

Result !!

1 corn flakes box later all is now as it should be.

Will ordr proper gaskets tomorrow but happy now.

[E30BeemerLad]

Nice one!

Isn't life grand when it is a simple fix like that, just a bit of a cnut removing the manifold etc and then having to do it again, still at least she's healthy again

[Brianmoooore]

Glad it's not just me that gets these totaly unrelated coincidental problems!