Boosted Buick - Not idling right
 

hey, i completed my turbo project about a week ago, im from Australia and the engine is a 3800cc buick LN3 (v6), (its a 89 model car over here, not a buick car)

anyway, the setup was going hard for a bit,but i forgot to run the crankcase breather into a surge tank, but just generally get it off boost..that was for 1 day, i fixed it the next day

after 3 days of boosting it made lots of smoke and started running real rough, so i pulled over and got it towed home


i stuck it in the garage and investigated, heres what i found
- blown rear inlet valley seal
- partially melted inlet gasket (not between any gallaries)
- brown oil with plastic specs thru it (from inlet gasket)
- oil in the turbo airfilter inlet nozel thing (not from turbo, from crankcase breather as it was vented into the air pipe before the turbo)
- blown exhust gasket
- 3 fouled leads
- milky substance near back of block, looked like headgasket goo, not enough for a blown gasket tho and it was in the wrong spot for blown headgaskets

so i fixed all those issues but ive got a white smoke comming out of my crankcase breather (not alot, like a fog) which i think is just worn piston rings as the engines done 270,000km... top ends done 160,000km
oils still appearing in the turbo inlet, so im just leaving the crankcase breather unplugged for now and no oil is appearing into the turbo (its a brand new turbo)

now its making a CHING CHING CHING CHING noise which ive been told is probbly a exhust leak, not too worried about that as its not that loud

ok so the real issue, after the whole things fixed, running a 2 bar map sensor + 2 bar tune it idles rough (even on stock tune + 1 bar map sensor .. it ran perfect before on 1 bar before boost)

it revs fine, makes boost fine but once it gets between 800-2000rpm it starts to shake, my theory is a vaccume leak??? but im not sure, im just looking for idea's really.. im gonna get under it tommorrow as im replacing engine mounts and upgrading the brakes on it... bottom end should be fine except for worn rings as if it were bottom end, id know about it..

also my BOV isnt working, so i get massive compression surge, it was working till one day...

any help would be awesome

Re: Boosted Buick - Not idling right
 

Crankcase needs to be ventilated better.

Rough idle... compression test that biznatch. Sounds like you might have toasted an intake manifold or headgasket.

Welcome to boosting without wideband, or reading plugs, and just giving it hell "but it's only for a few days" :-\ When you get old, somewhat bald, and bitter, this sort of thing doesn't happen to your cars anymore.

Re: Boosted Buick - Not idling right
 

lol, yeah i toasted a inlet gasket, just replaced em, but i think ive nailed it down to a vac leak as it idled better when i disconnected my bov + boost gauge

Re: Boosted Buick - Not idling right
 

ok,

im getting 10inHG apon idle (of vaccume)

i should be getting 21 or so,

Re: Boosted Buick - Not idling right
 

Is the vac line feeding BOV and boost gauge create big enough a leak to stuff you at -10"? That's a pretty big line to do that.

Re: Boosted Buick - Not idling right
 

nah its not...

ok... found

oil + water (fair bit) out exhust pipe (end of the pipe)
u rev it and vaccume goes to 20inHG, as soon as it drops below 1500rpm the vac drops to 10inHG

Re: Boosted Buick - Not idling right
 

compression test = all cyclinders down... diffrent rates, could be chipped piston, blown piston rings, cracked block, cracked heads... anything really picking up a new engine end of the week

Re: Boosted Buick - Not idling right
 

get some waste gate free pulls in before you swap the engine out :)

Re: Boosted Buick - Not idling right
 

oh man

Re: Boosted Buick - Not idling right
 

Prolly blew out ringlands.. dats my moneys.