210,000 miles, down on power. Any hope?

"Jake - Has Bad Luck So You Don't Have To" (murdersofa)
03/21/2014 at 13:42 • Filed to: None

(fucking Tiger. It took me 5 minutes to find the 'compose' button)

3800 Series II naturally aspirated circa 2000. 210,000 miles, all on synthetic, been well-maintained, and last year got all new seals, spark plugs, and filters, yet the car is still a good 2 or 3 seconds slower to 60 than it should be.

Are there any reasonably simple things I could do to eeke out a bit more acceleration from this heavy hombre?

All I can really think to do is replace the super-constrictive airbox (designed for quiet not power) with an oil-free conical air filter.

DISCUSSION (16)

Party-vi > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 13:44

New plugs, filters and seals won't fix blow-by. How's your oil consumption? I'm assuming the 3800 has hydraulic lifters - maybe they're worn out and not pumping up to where they used to?

Jake - Has Bad Luck So You Don't Have To > Party-vi
03/21/2014 at 13:50

After replacing the main transmission seal it has stopped emulating BP, so I'm holding oil quite well and it doesn't appear to be burning it.

I honestly don't really know about the lifters. My dad is of the notion that "the engine runs and we jut dumped $3000 service into it so it'll keep running for years" but I am of the mind that if I've lost that much power there's something not optimal with it. I'm not an engine technician, I just read Jalopnik/oppo and watch lots of car shows (MCM, roadkill, top gear, etc. not the best way to learn about things but it's passive learning and I'm lazy).

davedave1111 > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 13:51

Have you checked the engine management sensors? If the ECU is in some no-signal mode, you might be losing a lot of power that way.

Jake - Has Bad Luck So You Don't Have To > davedave1111
03/21/2014 at 13:54

I need to read more. I'm having a hard time googling what you guys are suggesting I check. I'm going to take my best guess and assume engine management sensors are things like the O2 sensors that let the engine adjust timing/fuel mixture on-the-fly for better power/efficiency?

According to my book-o-maintenance the O2 sensors were replaced last a couple years ago, along with pre-emptive replacement of the front axles.

Party-vi > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 13:56

Weeeeeeeeeeeeeeeell, after over 200,000 pistons rings show signs of wear, your camshaft lobes are probably a bit worn out, lifters are old, O2 sensors are probably a bit old and dirty. It's just getting worn out. You can't expect to have close to the same performance when it's been put through so many miles. Valve stem seals could be worn as well, compression could be down from this and piston rings. Do you have any oil on your air filter? My Cherokee was so beat to hell it looked like the oil filter was dunked in 30-weight every time I went to replace it.

Jake - Has Bad Luck So You Don't Have To > Party-vi
03/21/2014 at 14:00

Ah, I just noticed your mention of blow-by. That's probably a fair assessment. Damn.

Yeah, the air filter looks crisp white. Not sure about the oil filter.

I guess this gives me a bit more encouragement to go find a trashed Pontiac with a supercharged 3800sII and dump it into my crap body because sleeper.

Party-vi > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 14:01

I was going to say, just find a supercharged 3800 haha.

Jake - Has Bad Luck So You Don't Have To > Party-vi
03/21/2014 at 14:03

Cursory look at Craigslist reveals an ideal candidate lives in Tulsa for $2000. Rear-ended car with a salvage title. I could yank the engine, load it on a trailer, and sell the rest of the car for scrap value to pay for the gas to go down there.

Time to save my pennies.

Party-vi > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 14:04

Damn skippy. Then you'll have 240hp and tons of torque.

davedave1111 > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 14:07

Yeah, that kind of thing. I don't know about your specific engine, but usually there's at least a knock sensor, an air-intake sensor (MAF?), and a lambda sensor in the exhaust to measure the oxygen remaining - that one's probably what you mean by O2 sensor. There's also probably some temperature sensors involved.

It's quite plausible that it could be something really simple, like the engine-coolant sensor has failed so the ECU thinks the engine isn't warming up, so doesn't give you full power.

Jake - Has Bad Luck So You Don't Have To > Party-vi
03/21/2014 at 14:15

$400 for a supercharged 3800SII in Tulsa. Wow. No mention on if it comes with a tranny or not, but the Buick Rivera it cam from would do 0-60 in 7 seconds.

And my friend has an engine lift.

[want intensifies]

Jake - Has Bad Luck So You Don't Have To > davedave1111
03/21/2014 at 14:17

I doubt it's the coolant sensor. The car has an LCD that I can toggle through things like coolant temp, oil pressure, and... something else I can't remember. Bugger.

All those readings seem normal, so if it were a sensor issue (no error codes being thrown out) then it would probably be the MAF or the other sensor shoved between the cat converters (I think that's the lambda sensor you're referring to).

Any easy way to check them?

davedave1111 > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 14:22

I don't know specifics for your car, but normally you can google up what the sensors should output and check them with a multimeter to see if they're in spec.

Jake - Has Bad Luck So You Don't Have To > davedave1111
03/21/2014 at 14:25

Awesome, thanks for pointing me in the right direction!

davedave1111 > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 14:26

It's a direction, but I don't know if it's the right direction...

jvirgs drives a Subaru > Jake - Has Bad Luck So You Don't Have To
03/21/2014 at 14:59

the flux-capacitor has probably started to go bad