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Tune up the 05 Grand Prix with 3800 III

A little light goes a long way. What a ridiculous amount of fasteners.

Edit-Turns out you don't have to take the splash guard out to be able to drain the coolant from the radiator. The drain plug is on the driver side of the radiator on the back side. Easy Peasy.

Getting all the coolant out of the motor a bother though. Think I'll run it till it warms a bit and see what happens.
 
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I have a 99 gp gt. I replaced my fuel filter and it helped alot. It is underneath the driver side door on my car. Not sure if yours is the same or not
 
Got this all done.
Unbolted the dog bones and used a bottle jack under the engine, pulled the upstream O2 sensor, then was finally able to get to #6. Yea, I broke that plug trying to put it in. Replaced it and all is well.
Whew. Glad this is done.

Edit-I'll post up some pics later. Turns out putting fluid in the PS pump takes that whining away. lol, I had to crawl under the car while it was up on ramps to take the cap off and put it back on. To fill it, I had to tape a hose onto a long funnel. No wonder those things don't get filled often enough.
 
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Do Rag said:
Edit-I'll post up some pics later. Turns out putting fluid in the PS pump takes that whining away. lol, I had to crawl under the car while it was up on ramps to take the cap off and put it back on. To fill it, I had to tape a hose onto a long funnel. No wonder those things don't get filled often enough.
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I have a couple scars on my hand from topping that up. such a PITA
 
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I think I'm done with this car for a while so thanks for all the help. I hope someone finds this work log useful.

Jon.
 


It's now two year later and the car is back on the radar. Runs like crap, throwing codes, and generally being a nuisance.
P0300=Random Misfire
P0128=Coolant Temp Below Regulating Temp.
I won't be looking at it again till next week but would love to have some ideas about where to go. AFAIK, no other work has been done to the car besides my tune up in this thread. I plan to check the spark plugs but don't really know what else to do. Suggestions?
 
A. It's under the MAP sensor in the upper plenum. You need to remove the MAP sensor by turning it ¼- turn while pushing down. Remove the sensor and the PCV should be under that. Reach in with needle nose pliers to grab it.
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REMOVAL PROCEDURE:
  1. Remove the injector sight shield from the fuel rail and intake.
  2. Remove the MAP sensor (1).
  3. Use a 16 mm socket to press the access cover (2) down and rotate 1/4 turn counterclockwise.
  4. Remove the access cover.
  5. Remove the PCV valve (3) and the O-ring (4) from the intake manifold.
INSTALLATION PROCEDURE:
  1. Install the crankcase ventilation valve (3); replace the O-ring (4) if necessary.
  2. Install the access cover (2).
  3. Install the MAP sensor (1).
  4. Install the sight shield.
http://autorepair.about.com/library/a/1a/bl338a.htm


 
The PCV valve is going to cause random misfire?
It is intermittent but does happen a lot. I'll ask him if it happens more or less after it's warmed up.

Thanks btw. Spending the time and the brain cycles to help "some guy" on the internet doesn't pay well but it sure helps me a lot.
 
 
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I put a can of Sea Foam in the tank last week and he says it helped a bunch. Still not 100% though. I wonder if the fuel pump is going out?
 
I've had a random idle shudder in my car the past couple years but it never throws a code. I've replaced plugs, wires, pcv, cleaned throttle body. Nothing really helped the occasional shudder.

Hope you figure yours out so I can try it on mine :) 2008 grand prix 3800 III N/A - 86k miles.

I like your walkthrough btw, especially the pictures.
 
As far as I can tell this car doesn't have a proper fuel filter, and dirty injectors would cause this. That would also explain why the Sea Foam was so successful. I thought Chevron gas was supposed to prevent this kind of thing.

Napa does cleaning and flow testing but it would take a couple days and $150 dollars and I'm not completely sure that would fix it. He seems satisfied enough so I'm leaving it here for now.
 
Don't ever think chevron gas is special or any brand of gas is special. All the trucks go to the same refinery and get their fill from the same holding tank. The biggest factors in gasoline stations are the age and quality (conensation, debris etc..) of the tanks there stored in.
 
91parkave said:
Don't ever think chevron gas is special or any brand of gas is special. All the trucks go to the same refinery and get their fill from the same holding tank. The biggest factors in gasoline stations are the age and quality (conensation, debris etc..) of the tanks there stored in.
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The Wiki page says Techron is supposed to make Chevron one of the top tier gas products. The page also says it might just be an ad and asks for a better write up. lol.
 


blueguy91 said:
Just take off the dog bones and remove those pointless engine brackets by the coil pack bracket and the one in the back...it'll give you tons more room to work with...also...nice to know that GM still used the U-Bend in later model cars...I thought they didn't.
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not sure when they changed it but my 2008 has no such bend
 
Do Rag said:
The Wiki page says Techron is supposed to make Chevron one of the top tier gas products. The page also says it might just be an ad and asks for a better write up. lol.
Click to expand...

I used to work for racetrack similar to quick trip when I had to do the logs for incoming fuel it would all come from the same damn tanks I actually had to go up there with my discrict manager and you see all the top brands trucks rolling into the same place for fuel I was like damn lol
 
Something I noticed, but forgot to mention, was that the guy doing to work didn't use iridium plugs. Isn't that a big deal for this engine? He used platinum...
 
Well, how is the situation now? Mind keeping us up to date? I had the P0128 on an impala with the 3.8, a new thermostat should solve it. I ended up just flushing out all of the dex cool and replacing both the thermostat and rad cap.
 
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