Tweet
my daily driver is a 96 Buick Riviera non SC. It ran great until yesterday evening when I let it warm up after work. Ran fine went inside came back out 10 minutes later and a whole bunch of condesation was coming from the tail pipes and it was running extremly rough. The SES light was flashing so I knew something was wrong. I had to get home so driving home the SES light would flash then stop flashing but stay on. Half way home it ran normal for a few seconds then started back to running rough. Then the low coolant light came on shortly after that. Got it home and checked the water and it was low but not far enough for it to overheat. Checked the oil and it looks like it has some water in it. Not milkshakey but a light brown. Used a code reader to see what the PCM had to say and it gave code 300 which is multiple cylinder misfire. I figured it was that code because of how rough it ran. I was hoping for some other codes but 300 was the only one. Any Ideas??? Does this sound like the intake manifold gasket needing replaced or could it be worse?
-
-
Re: 96 Buick 3.8 running rough
EGR passhe has burned through the TB deicing passage and is dumping coolant into the engine. Fix is to replace the plastic intake.Central TEXAS Sleeper
USAF Physicist
ROA# 9790 -
Re: 96 Buick 3.8 running rough
ctx is right i think the upper intake on thoes go bad on a regular basis, enough that you can get them aftermarket as well as from the dealer. it should be just upper plastic peice that is messed upComment
-
Re: 96 Buick 3.8 running rough
Was looking online last night . the replacement parts didn't quite lookright . That explains why .Comment
-
Re: 96 Buick 3.8 running rough
CSX has it. Been there - done that, have the flat wallet to prove it. Mine always died when we were on a trip so I had to hire it done, so consider yourself relatively lucky. GM knows this is a problem and may warrant it depending on miles, years, service record, etc.
We traded it in after the second failure........
Later
DanComment
-
Re: 96 Buick 3.8 running rough
Been there done that on two different cars. It is usually the lower intake gasket. They don't get along with the Dexcool coolant. Just do a google search for dexcool and you'll see what I mean. Happened on a 2002 Impala 3.1 and a 97 Sklark with 3.1. Still need to fix the 3.1 Anybody have experiance with pulling the engine out of the bottom of one of these? When it dumped the coolant it spun the bearing. Did a cheap fix to at least get it running. Few months later it broke the cam shaft in half. From what I have found this seems to be a fairly common problem. Give me a good old small block Chev any time!!Comment
-
Re: 96 Buick 3.8 running rough
Nope.
In the case of the 3.8l v6 w/ plastic intake,
heat cycling, and ham fisted mechanics can cause these
to prematurely split the o-ring seal, or crack the
plastic.Comment
-
Re: 96 Buick 3.8 running rough
not the dexcool causing this , over tightened or loosened bolts
I don't usually see too many vavuum leaks on 3800
maybe your plenum is starting to leak causing your misfire
my brother has 200 k on his 99 grand prix 3800 - original intake and dexcool hee heeComment
-
Re: 96 Buick 3.8 running rough
3.1 is a Chevy Metric 60 V6, the 3800 is a Buick 90 V6. Different designs. Usually its the upper plenum that has a burn through from the EGR passage causing it to dump coolant. However in replacing it its real easy to mess things up when you're used to working with metal intakes and you crush the crap out of a plastic one.Central TEXAS Sleeper
USAF Physicist
ROA# 9790Comment
-
Re: 96 Buick 3.8 running rough
VortecRS 's uncle was coming over tonight to take a look (my bro-in-law ) he's done one of these before so he's going to give him some pointers on how to go about this. I got over there last night and well.....lets just say I'm not a front wheel kind of guy and I got a little over whelmed. We started looking at the camaro that caught on fire a while back thinking maybe we could get it on the road faster.
Hey vortec, what'd uncle say ?Comment
-
Re: 96 Buick 3.8 running rough
I've got the intake off the car now just wondering what this plastic tube is doing held over the gasketComment
-
Re: 96 Buick 3.8 running rough
Got every thing back together about an hour ago but it is not starting. Turns over but will not fire. Any Ideas?Comment
-
Re: 96 Buick 3.8 running rough
1st, I'm wearing the shirt with that tag line on it right now....
"I reject your reality and substitute my own"
Check to see if you have reconnect all the sensors, injectors, and the plug wires in the right order. I crossed 2 wires on my Regal and it wouldn't fire till I got them on the right plugs. Probably missing the TPS or other top end engine signal.Central TEXAS Sleeper
USAF Physicist
ROA# 9790Comment
-
Re: 96 Buick 3.8 running rough
don't forget to change the elbow from the intake to the tensionerComment
-
Re: 96 Buick 3.8 running rough
tried cleaning the spark plugs up but that didn't work so I bought a new set and runs great thanks for the helpComment
Comment