Rough Idle ??? 2003 Vue V6 HELP!!

[hillbillydave]

I have a 2003 Vue with the V6 automatic FWD.I just had the check engine soon light come on.The only thing I notice is a rough idle. I had Autozone check the codes and came up with PO300,PO301,PO303 and PO305.The guy at AZ said it probably only needed some new plugs and plug wires.I don't know,can it be that simple or something else ?

[fdryer]

DTC P0300 Engine Misfire Detected
DTC P0301 Cylinder 1 Misfire Detected
DTC P0303 Cylinder 3 Misfire Detected
DTC P0305 Cylinder 5 Misfire Detected

It would depend on some things like mileage. How many miles? What makes this an odd problem is that there's a misfire from the other cylinder bank, #5, making this problem neither an ignition module or plugs related but something possibly upstream from the cylinders common to both banks. The MAF sensor may be the problem. If the mileage is around 100,000 the plugs should be replaced as a rule but may not be related to this symptom. Any one perform any maintenance recently that may have loosened the individual flexible couplers to each intake runner? A crack in one had one V6 engine run with a lean problem until found by spraying throttle cleaner around the flex couplers until the worn/cracked one sucked in fluid to lower rpm's.

[BobbyP]

That's a wise way of finding the leaking flex coupler!

[hillbillydave]

The Vue has 72,000 miles. I changed the oil about a month ago but nothing else.This just started a couple days ago.It seems to idle rough after the engine warms up.sometimes the light will flash but mostly it is just on.

I was trying to find the plugs but have no idea where they are located:xeye:
I thought I was more mechanically inclined.

[fdryer]

Please update your personal profile to reflect which engine you have as I'm presuming the 3.0L V6 and not the Honda. Being a little familiar with my 3.0L V6 and the commonality between the L-series and Vues before Saturn decided on a somewhat better Honda engine for the Vues, your mystery plugs are hidden under the two ignition modules (a la Corvette style from years ago) that are in plain site under the two intake runners. An ugly looking black epoxy encapsulated rectangular object running the length of each cylinder bank under the intake runners is the expensive ignition modules. They fit directly over the three spark plugs, eliminating the plug wires in what's described as direct ignition with another term, coil-over-plug design. They're completely trouble-free until one fails where the entire module is replaced. One ignition coil per spark plug. If we're still discussing the 3.0L V6 engine, you'll have to prepare yourself for the ensuing nightmare to simply replace the plugs when they're due (@100k miles and thankfully at long intervals); disconnecting each black flex coupling clamps carefully (posted by other members), removing the intake runners from each cylinder bank before having access to removing the ignition modules that now exposes the six spark plugs!? :hmpf: All I covered are the high points as you look over your engine. Saturn likes to play "let's hide the spark plugs and do away with the plug wires". It works for Corvettes so it works here too. Now you know. :cool:

Its been said that a flashing SES indicator is not a good sign as it points to catalytic converter damaging faults if allowed to continue. Be careful and mindful of the flashing SES light.

[hillbillydave]

The engine is a 3.0 V6 ohc. so probably a sensor and not the plugs.
Thanks for the help

[guitarzan]

I agree with fdryer. Please update your profile so your posts show more info about your vehicle.

at the top on the left side, click UserCP.
next screen on the left side, click Edit Profile.

fill in your vehicle information and that will help those who are trying to help you immensely.

[1saxman]

Jeez, guys, it's a 2003. The Honda engine didn't start until the next model year.

Find out quickly what's wrong with it. If it turns out to be the ECM, you may be able to save $1000 because the emissions warranty was extended to 8 years/80000 miles. At least that's what they told me when one of mine went bad this spring.

[hillbillydave]

I'm not the original owner,will the warranty still cover the ECM ?
Is there a step by step or how-to article available for spark plug replacement for the '03 V6 3.0 ? Any help or suggestions would be appreciated.

[Gerry Proctor]

There is a diagnostic path for misfire codes. It starts with a TechII scanner individually triggering the ECM to signal the ignition module to test fire each individual plug with the ignition on and the engine off to hear for a plug fire. If no plug fire, then you start testing the system up the line to see if the ignition module is receiving a command. If the ignition module is receiving a command from the ECM but it won't fire the plugs, then you replace the ignition module for that bank. If it isn't receiving a the EMC command, then it calls for ECM replacement. If the plugs do fire and the rest of the system is in order, the diagnostics path leads you to fuel system diagnostics. The very last thing in the path is replacing the plugs.

I can understand you wanting to save money and hope you have some luck with replacing the plugs. And if that's the path you want to take, you can search the forum for "intake manifold lift" and give it a shot. It's a complex task and bills for five hours. There is no way to get to the plugs except to lift the intake manifold. No shortcuts here.

I would probably drop the car off at Saturn service and let them diagnose the car and make the repair. You'd probably be well ahead in time and maybe money too.

[ksion15]

1 3 and 5 are on the same bank. i'd try a coil. sometimes the timing belt slips off a tooth or two on one of the cams causing misfires. but like i said, i'd try the coil first. the warranty on the ecm is 8 year 80k miles, by the way.

[hillbillydave]

I was driving my vue today and it seemed to get worse the further I went.at times it would shake the whole car at around 50mph.I think it is acting more like the coils than the plugs.

[fdryer]

ksion15 is correct about the cylinder 1-3-5 under one ignition module, the rear bank near the firewall side. It could be the ignition module or loose connection. The difficulty to troubleshooting DIY is not having a scan tool to help look at real time data and you're left with buying an ignition module that isn't interchangeable with both cylinders.

ECM's as a rule don't fail.

[hillbillydave]

well I decided to let the experts have it. I took it to the Saturn dealership today .It sounds like it might be too much for a shade tree mechanic

Thanks for all the input.
I will let everyone know the outcome.
Hillbillydave:)

[hillbillydave]

well I got my Vue back from the dealer Wednesday.The timing belt had slipped a few teeth and was out of time.apparently someone prior to me had the timing belt changed and damaged the cover allowing dirt and debris get into the belt.$400 later I'm as good as new with a new belt and cover.

Thanks for all the help.
Hillbilly Dave

[VTchemist]

well I got my Vue back from the dealer Wednesday.The timing belt had slipped a few teeth and was out of time.apparently someone prior to me had the timing belt changed and damaged the cover allowing dirt and debris get into the belt.$400 later I'm as good as new with a new belt and cover.

Thanks for all the help.
Hillbilly Dave


Someone replaced the timing belt and you only have 72K on it? Did you buy it from a dealer or a individual? If you could get access to the records, it would be worth it to see if they changed the plugs when they did the belt. The V6 on the 2003 (L81) requires a lot of disassembly (and costs a lot of labor time). If they did the plugs when they did the belt, you should be able to avoid the big bill of the 100K service.

BTW if you have the automatic, the transmision should be serviced at 60K intervals, and not the 100K in the owner's manual.