: Tune up time?

03-02-07, 02:12 PM
Do Northstar engines eventually require tune-ups?

I own an 01' DeVille that just clicked over 80K on the odo. I may be imagining things but it seems like there is a bit of "sputtering" when I accelerate from a low speed (such as merging onto a highway). After a few short seconds it feels as though Ive been rear ended by a semi and the car takes off. However it used to be a smooth launch from low end speed all the way up to the triple digit zone.

Anyone else with NStar motor ever experience this?

03-02-07, 06:44 PM
2000+ does not have plug wires so about the only thing involved in a "tune up" would be plugs. Stick with A/C Delco. Might want to do a TB cleaning also if it has never been done.

03-03-07, 10:17 AM
if you search there are a listed number of recommended items that should be checked/replaced during a tune-up. The plugs are supposed to go 100k miles but it's better to replace before. Also, the fuel filter needs to be replaced, check the fuel pressure regulator and potentially replace, throw some fuel injector cleaner in the gas tank to clean the injectors, or if you're really picky, remove all 8 injectors and have them blueprinted and flow matched. May be time to change the transmission filter screens and replace the tranny fluid, also change your coolant, add the pellets to the lower radiator hose. Check power steering fluid levels, change your air filter and oil...

03-03-07, 09:56 PM
In regards to the sputtering I would start by doing the routine recommended TB cleaning. That's a problem for all N* if you don't' take them out and whoop once in a while.

As far as injector cleaner goes we all agree that's it's bad for more parts in the car than it is good. Use it in small doses. I would also recommend Lucas or, what's the other one Techron or something. Both of those are good but don't over do it thinking it will work better. Use no more than the recommended amount.

03-06-07, 10:26 AM
Thanks for all the great advice.

By the way; now my "service engine soon" light is on. Bad luck for me I guess. There doesnt seem to be anything else wrong with the engine; other than what Ive indicated earlier.

Could this just be a faulty signal? Im considering taking the car to my local Cadillac dealer to have a look see.

03-06-07, 06:12 PM
Your sputtering and the service engine light are connected. Do not take to the dealersip. They will take your money for something you can do yourself easy. Your engine is misfiring. That is causing the sputtering. Now, the check engine light is on because the engine is misfiring. The misfiring is letting unburned fuel go. This is setting off the O2 sensor as an emission problem. Your engine does not have spark plug wires. That out the equation, whats most likely left is either the spark plugs, or the coil pack over top of your spark plugs. I would replace the plugs anyway, even if they aren't bad. Use ACDelco. I used Bosch and they suck. They won't even last 1000 miles. Once you change the plugs, and you still have the stuttering, you probably have a coil pack problem. I have a 99 Deville. I don't know how to diagnose which pack is the problem on your car though. On mine, I took the plugs off the pack one at a time and stuck a screw driver to the post one at a time until I didn't see a spark. Gotta ground the screw driver. I wrapped wire around it and to the engine mount. On my N*, each coil pack is about $30. I don't know how much yours are. But you can do it yourself, no dealerships! And once you fix the misfires, the check engine light will go away after about 100miles.

03-07-07, 09:51 PM
I'll give that a try. Any time I can save a few bucks from going to the dealer is a - ok with me, thanks.

03-09-07, 09:24 AM
Start by pulling the codes to see what tripped the "service engine soon" light.

03-09-07, 11:06 PM
How do you "pull the codes"? (Ive never done that before).

03-10-07, 04:30 PM
Check the "sticky" in the Tech Tips section.

03-11-07, 04:15 PM
Ok - I pulled the codes. Can anyone decipher these? Here they are exactly the way they appear from the dashboard.

B0429 - Temp Cntrl # 3 rear circut range
B1004 - Keep alive memory (KAM)
U1016 - Loss of Communications w/ pcm
P0420 - Catalyst system low efficiency

03-11-07, 04:23 PM
Here are the codes I recieved after going thru the steps to check for Diagnostic Trouble Codes:

B0429 (temp cntrl # rear circut range)
B1004 (keep alive memory - KAM)
U1016 (loss of communications w/pcm)
P0420 (catalyst system low efficiency)

Anyone know what these mean or ever had these codes / problems?

03-11-07, 06:01 PM
B1004 & U1016 could be from pulling battery power. I'd clear them.

P0420 seems to be telling you that you may be in need of a new CAT. Keep in mind that the Gov't mandates that they be warrantied for something like 80K.

B0429 is telling you that the rear temperature control air mix door does not match the commanded setting. It does not take much. Unless you are having a problem with it, I'd ignore it as well. I have/had the same DTC and mine is still under warranty. Rear temp works fine, so I told the dealer not to bother replacing the unit.

03-12-07, 06:35 AM
Ok - can anyone decipher these codes I obtained? -

B0429 - temp cntrl #3 rear cir range
B1004 - keep alive memory (kam)
U1016 - loss of comm w/pcm
P0420 - catalyst sys low eff

Do any of these codes sound familiar to anybody?