2001 Chevy 3800 Series II V6

[ehenry]

I drive this vehicle for work. It developed a miss so I took it to a local shop for tune up. After plugs, wires, a couple sensors and reading the codes the miss was still there. The shop did a compression test and number two cylinder showed only 50 lbs. Out of curiosity I took a piece a paper and held it to the exhaust and it sucked the paper to the pipe every time it missed. Doesnt this indicate a burned exhaust valve?

 

[Scott Danforth]

Re: 2001 Chevy 3800 Series II V6

do a leak down test. could be carbon, could be a burned valve, could be something else.

 

[ehenry]

Re: 2001 Chevy 3800 Series II V6

The shop I took it to did run a can a SeaFoam in through the brake booster vacuume line and let it sit over night and there was no change. I asked the mechanic how that works. He said they pulled all the spark plugs out and started spinning the engine over and poured the SeaFoam down the booster vacuume line. I'd always heard about this being done but wasn't sure exactly how it was done.

The folks I work for aren't really wanting to put a bunch of money in to the car due to the age and mileage (101k) but the car is an other wise solid, good driving car. I work for the county where I live and I was thinking about talking to the mehcanics at our road department shop and see if they would pull the head off the car and seeing if they can fix it. If they cant and the head has to go to a machine shop, any one here have a clue what cost of a rebuild would be?

 

[Scott Danforth]

Re: 2001 Chevy 3800 Series II V6

usually a burned valve would read 0. carbon buildup would account for a low reading, and so would rings.

pull the spark plugs, do a leak down test.

if it is a head or a complete engine, the 3800 was one of the most common engines out there, only second to the the SBC.
LKQ has complete engines listed for $350 at many of their pick-n-pull yards.

assuming you need a complete head refurb with all valves, etc., somewhere between $150 and $200 for a single head, however if its just one valve, it would be less.

Rockauto has complete refurbed cylinder heads for $184 a piece plus core

 

[BlkY2k]

Re: 2001 Chevy 3800 Series II V6

3800s are famous for intake manifold leaks, Plastic plenum and lower gasket. Spray some carb cleaner around the base of the manifold with the engine running and see if it makes a difference. You can also start the car and try to remove the oil filler cap, if it trys to stall or suck the cap back down you`ve got a leak. Shops charge all different prices to replace but it really is a easy fix, I`ve got it down to about a hour and a half now. G/L

 

[halfmoa]

Re: 2001 Chevy 3800 Series II V6

I've had two of those engines. One was a 1990 Buick Regal Gran Sport and one was a 2001 Pontiac Grand Prix GT. Both had the transmission go out right at 110K miles. Just my experience but I wouldn't put a whole lot of money in the engine if it was me.

 

[ehenry]

Re: 2001 Chevy 3800 Series II V6

This is a county owned car....its actually a police package Impala. I' ve been driving it for four plus years. It uses no oil at between changed, it runs like a scalded ape when its hitting on all 6 cylinders. but with the age of the car and the mileage on it the county isnt going to put a much more money in to it than they already have. I'm going to see if the mechanincs at the road department will look at it and see what they can do. Typically they wont work on any vehicles other than their own BUT I do quite a bit of work for them and have a pretty good rapport with those guys. Its worth a shot. If its an intake gasket, which I kinda doubt because of it sucking back throught the exhaust, they could do it for next to nothing. we will just have to see.

Also, I dont think this is one of the Buick V6's I think its a Chevrolet. I had a 3800 in a Old 88 and the one in this Impala is built totally different.

Thanks to all yall that have replied....I'll let ya know how this turns out. They have told me to just drive the car like it is....run it till it pukes type attitude but I know when it does I'll be back to riding in my own vehicle until the supervisors or the Sheriff decides to replace some vehicles and I get another hand me down. I'm looking at it as.........A raggedy ride is better than a dressed up walk!

 

[Scott Danforth]

Re: 2001 Chevy 3800 Series II V6

the 3800 is a buick derived engine. it is also known as the corporate V6. there was the 3.8 liter which became the 3800 which became the 3800 series II. all based on the 1963 engine architecture originally found in the Buick Special.

FYI - a mildly tweaked 3800 will put out 330hp naturally aspirated and spin about 8500 RPM.

 

[dolluper]

Re: 2001 Chevy 3800 Series II V6

Spray some oil around #2 injector....at intake.....see if rpm's change.....if so replace both injector gaskets take note not to mix them up..different colours just beware of it

 

[RogersJetboat454]

Re: 2001 Chevy 3800 Series II V6

Spray some oil around #2 injector....at intake.....see if rpm's change.....if so replace both injector gaskets take note not to mix them up..different colours just beware of it

Unless this is a direct injected engine (which we both know it's not), I don't know how a leaking injector seal or intake would result in 50 Psi in number two hole. He could do a compression test with the intake laying on the bench, and it shouldn't make a lick of difference.

Best thing to do is a leak down test to see if he can nail where the compression loss is coming from. Unless this thing is suffering from an injector leaking fuel thats washing the oil off the cylinder walls, he's ultimately gunna need to pull this apart to fix it.

 

[dolluper]

Re: 2001 Chevy 3800 Series II V6

Well thats nice RJB54.....I was` addressing a miss in# 2 not a compression issue.....you should know that......jump on it A....I do understand engines thankyou......boy still learning after 45 years and willing.....as most as long as we are breathing

 

[RogersJetboat454]

Re: 2001 Chevy 3800 Series II V6

Well thats nice RJB54.....I was` addressing a miss in# 2 not a compression issue.....you should know that......jump on it A....I do understand engines thankyou......boy still learning after 45 years and willing.....as most as long as we are breathing

50 psi of compression in that hole = a miss.
It's an obvious problem that needs further exploration, should we look any further at this point?
My comment wasn't a personal attack against you, or your mechanical abilities. It's how I would phrase it to one of my co-workers who suggested the same diagnosis, regardless of their tenure turning wrenches. I'm just trying to understand your rational so perhaps I could learn something that I may have not known.

Respectfully,
RJB454

 

[dolluper]

Re: 2001 Chevy 3800 Series II V6

If in fact it has a burn't valve.....discovering the cause may help the health of the fix.....these little injector {o-ring style}gaskets can devlop leaks causing a lean condition {vaccum leak} which heats up the combustion chamber....and may in cause a valve to burn ....I suggested this to find out if it were a possible cause of the problem and easy not time consuming thing to do before you start any dismantle of the engine