ECOTEC idle problem

[syk35]

Hi guys.

My ECOTEC in my vs II ute (200,000ks) is suffering rough idle now and then. About 30% of the time my car is idleing at the traffic lights it is rough. The car never stalls, this problem is not normal. The engine runs fine throughout the rest of the rev range.

I have serviced the car recently (as always)
-new plugs and leads (4000k's ago)
-new oil and filter (500k's ago)
-new fuel and air filters (4000k's ago)
-cleaned IAC valve and throttle body (last weekend)

Today i removed the spark plugs and checked the gap and condition. The plugs on the driver's side (2,4,6) appear to be good. The plugs on the passenger's side (1,3,5) appear sooty, as if its running rich. I also performed a diagnostic check on the computer and got a code 12 (no faults present).

Do you think that the passenger bank of cylinders could be running rich because of a stuffed oxygen sensor? would this occur if the oxy sensor is stuffed? Would this make my car idle a little rough now and then?

Thanks in advance

[hako]

Your reasoning sounds pretty good though I wonder why the codes came up good. The cost of a new oxygen sensor is minimal so I'd go for that. Have you checked the wires to the PS oxygen senser for integrity.

[syk35]

Not really. I will on the weekend. Should i buy two new oxygen sensors, or just the one? Anything else i should look out for?

[boojak87]

If your car just idles bad (but rpms don't fluctuate and not to the point of stalling)...i'd be looking into injectors. If i were you, run a bottle of nulon injector cleaner and fill your tank up with premium next time you go to servo... After that tank, if you notice an improvement in throttle response and even the slight possibility of better idle, it's your injectors. I had exactly the same issue. Had fuel filter, plugs, leads, air filter, oxy sensors, crank angle sensor, thermostat all replaced and throttle body and IAC valve cleaned and reset, nothing fixed it and everyone who looked at it said "No, no no, not injectors, can't be, don't waste your money" haha some help they were!!! But i had enough of it and went against their wishes and got them cleaned and rebuilt and voila! Can't even feel the idle now...can't even tell if the car's on. Idles brilliantly, response is killer and i shall see if i get better fuel economy (as i have just had them done last Thurs) within the next week or two. A lot of them time your first instincts are usually the correct solutions. From what i understand though, if ECU pulls up a 12...then nothing regarding timing, sensors etc are gone, so it's a blockage or delivery problem down the lines. I immediately thought it was injectors but didn't act until just recently. Thank god i did now though, very pleased with the fix.

Oh yeah it might be a good idea to do the oxy sensors anyways with that amount of kms on the clock. As your old ones in there will be covered in crap.

Good luck with it mate hope you fix her,
Boojakz.

[syk35]

I ran injector cleaner through about 1000k's ago. i didn't help much. P.S. i also run the car on BP ultimate.

When can you tell if you need the injectors removed to be cleaned? like do i just keep on putting injector cleaner with the fuel?

I will put another bottle of injector cleaner in the tank. i will also order new oxygen sensor(s).

Anyone else have an opinion??

[nado69]

my car is having the similar problem at them moment.... hanged everything i can think of ... also ran nulon thru it... for a week or 2 it was good, then just today it stalled... when idling when my car isnt idling it runs perfectly fine... no problems what so ever.

[Spaced]

I ran injector cleaner through about 1000k's ago. i didn't help much. P.S. i also run the car on BP ultimate.

When can you tell if you need the injectors removed to be cleaned? like do i just keep on putting injector cleaner with the fuel?

I will put another bottle of injector cleaner in the tank. i will also order new oxygen sensor(s).

Anyone else have an opinion??

Supposedly with injectors you need to actually clean them with the additives it just runs it through your motor. You can get a "carbon clean" for your engine where they put it on a machine and it clean intake and everything for $135 - $200 so just shop around. Is your fuel consumption high? Did you run your error codes? BTW how much for oxygen sensors?

[boojak87]

Likewise. I had always run premium in the car. Used to run nulon through the tank once every 4 tanks. Would make it feel better for a little while until 2 tanks are run though, then again, lack of responsiveness but not once did the idle impove until after i had them out and cleaned. If your suffering from:
a) Rough Idle
b) No response (flat spots)
c) Poor fuel economy (200 - 300 (at the most) kms out of a tank)
I'd advise you to get the injectors looked at, especially if it has a rough idle but the rpms on your dash aren't low or fluctuating.

Cheers,
Boojakz.

[kopper69]

Oxy sensors will normally throw you an error code. What about plug leads? Test them with a multimeter,make sure that are really tight.

[danja]

I did my O2 sensors at around 160-170'000 kms. Didn't do a whole lot for the idle, but certainly made the car a lot more responsive, and dropped fuel consuption considerably. Before doing them it wouldn't be unusual for me to do 14-16L/100, now I average 12-13L/100, and have never hit 14L since, even when I have a "lead foot week".

Regardless of wether this is the cause of your idle issue, I'd recommend it every 80'000kms or so, from memory they cost around $200 for the pair, but it was a while back. Check Holden (pricey)/eBay/Autobarn/Supercheap etc.

[aussiepride94]

ahhhh engine mounts dude i kno its a wee bit long time leate but yeah engine mounts chek them

[MADDNE33]

i have the exact same problem in my vs ute. 270 on the clock and pretty sure everything is still stock motorwise. no error codes and a rough idle. although my few consumption is nomal. getting around 430 out of a tank.

i have done plugs and leads, oil change, fuel filter, clean intake manifold and ran several tanks of injector cleaner and always run bp ultimate.

ive been told by a few people to get my injeectors looked at but the price scares me haha.

sometimes ill start it and it was just stall.

[Brett_jjj]

You can get a set of 6 brand new injectors for $170 on ebay. They are only a cheap brand,but at least the are brand new, they wanted $100 for cleaned/reco bosch brand injectors,so I though Id try the cheap brand new ones first. My original ones have done at least 150,000 km that I know of.Ive gotta put the new ones in over the weekend..I will post up how they go.My local holden dealer wanted $120 EACH for genuine (bosch?) injectors,I could have got brand new bosch injectors for around $350 on ebay.But I thought Id see how these cheapie injectors go first.They couldnt be any worse than the old ones.

[The1]

Not really. I will on the weekend. Should i buy two new oxygen sensors, or just the one? Anything else i should look out for?

Reset the ecu so the fuel trims get reset, then start er up from cold, see if it idles crap then, if it does it aint o2's as there only used in closed loop.

[RX25SE]

Or try removing the coil pack, DFI module and bracket. Clean where the bracket mounts to the head and between the DFI and bracket. This is to ensure the DFI has a good earth. Also put some fresh zinc oxide grease under the DFI as a heatsink.

[justbad4you]

reco is somtimes as good as new.id go the bosch

You can get a set of 6 brand new injectors for $170 on ebay. They are only a cheap brand,but at least the are brand new, they wanted $100 for cleaned/reco bosch brand injectors,so I though Id try the cheap brand new ones first. My original ones have done at least 150,000 km that I know of.Ive gotta put the new ones in over the weekend..I will post up how they go.My local holden dealer wanted $120 EACH for genuine (bosch?) injectors,I could have got brand new bosch injectors for around $350 on ebay.But I thought Id see how these cheapie injectors go first.They couldnt be any worse than the old ones.

[The1]

reco is somtimes as good as new.id go the bosch

not if there the old metal ones, not like a clean and filters gonna make the springs and pintles new.

[PRAVX II S]

Lol.
You your not meant to put injector cleaner in your tank if anything it does damage more damage in your fuel injection system. That has been told from tafe and is a generally known in the trade.
The best why to clean injectors are to take them of the car and get them sent away to get cleaned. When they clean them they check the before and after flow rate of the injectors.

[Brett_jjj]

reco is somtimes as good as new.id go the bosch

Before I bought the new injectors,I phoned about 4 different EFI places,and asked a few questions about whether its worth getting some spare VT injectors Ive got, cleaned ,tested etc,and every time I mentioned that I could get brand new "cheap brand" injectors for $170 online ,every place said they wouldnt worry about cleaning the old ones when I can get new ones for that price.The EFI places around here all wanted $150 for the cleaning ,testing+filter replacement etc.They also said that once used injectors have sat around for a while,its apparently hard to get them flowing the same way they did when they were new, as they wear and corrode inside..They also said that most reco injectors are mixed and matched so the set all have similar flow rates,but apparently they will never flow as good as new ones will.So I just thought Id try these cheap ones,if they are no good for whatever reason,then I will just get brand new bosch brand VT ones.The VT ones are apparently better than the VS type injectors and they will fit straight into a VS.Its certainly different for me to buy "cheapie" parts.I always buy and fit genuine holden parts,I figured that because the new ones werent that much more expensive than the reco bosch injectors on ebay, theyve gotta be worth a shot to see how they go.Anyway I will post up how they go when I fit them.