Vectra SRI 150 - rough idle

MarkGolf

Hi guys!

I've just bought an X reg 2.2 SRI vectra off a guy in work merely to sell on as I bought it for pennies! Great condition etc etc.. The only issue is an idling problem!

When you first start the car after a number of hours it sounds like a bag of crap, really bad but for 5 seconds at most then it settles and just idles really bad, the revs sit at approx 600rpm and bounce upto 800..

Strangely, the car drivers perfectly, smooth as anything and does pull like it should! Apparently this fault appeared after an oil change where 5/30 or 5/40 was used! The strange thing is that you can take the car out of gear while moving and it will idle fine!

Late last night and friend and I think we discovered an exhaust leak where the exhaust manifold joins the downpipe but I dont think this is causing the rough idle..

I want to do the usual like clean the idle control valve (Where is this on the 2,2?)

The chains were replaced at 64k and the car is now on 95k..

I've done a fair bit of seraching on the forum but the results led to all sorts of possible issues..

Thanks for any suggestions

Turbo_Shane

Hi mate, Welcome to the site. It could be a number of things thats the thing. id start off with the easiest and cheapest things to do like.. cleaning out the throttle body, make sure the breather pipes arnt clogged, change fuel filter, check vacumm pipes ( mine was leaking slightly making it rev up and down on idle) . if not then the promblem could be slightly more costly?? o2 sencor, crank sencor, pre cat /cat blocked??

Try the first 4 things first mate and see how u get on??

dodger

The 2.2 engine does use an ICV it has a throttle body situated at the front of the engine.

Does it start ok for cold? Is difficult to start from when the engine is at it's normal operation temperature? If the answers to these are yes then it could be the EGR valve.

MarkGolf

Cheers guys

I cleaned the throttle body and checked for any air leaks last night but all seemed fine. Did what I could in terms of cleaning the egr but the prob persists.. I do have a small blow from where the pre cat meets the manifold but I doubt that this is the cause of my horrible idle issue!

The pre cat on the car was replaced earlier this year as the old one collapsed and blocked the exhaust, im sure the new one couldn't be dead already.. The car drives tooo welll anyway, it just idles horribly and the engine moves quite a bit! ekkkk

Micro

Hi all,

I also have a vectra sri 150 (44k) with exactly the same problem as MarkGolf has described, ive had a number of people try to diagnose the problem and after a owning the car a year still no joy. im very interested to know if you manage to cure it.

ive also found this on youtube, looks like the same fault again..

https://www.youtube.com/watch?v=Z1T43w9-gec

MikeS

do a compression test

usual rough idle is a worn throttle body, dodgeh EGR, worn CTS if based on temperature

vocky

duff egr valve, fit a blanking plate and see if that sorts it 🙂

egr plate: 24575592 = £3.50 from the dealers

MarkGolf

Took a vid of mine last night.. Will have a go at blocking the egr with some sheet metal and see if that solves it, if so i'll find where my local dealer is and get the proper plate!

Not the best vid really..

The idle is quite jumpy like that VX220 and the engine rocks back and forth..

MarkGolf

The sound seems different and you can't really see it rocking in that uploaded vid! doh!

Micro

My engine sounds the same and has a quite extreme rocking back and forth too, so much it rocks the car..., i have tried blanking off my egr leaving it connected and even tried it with no egr plugged in at all but it doesnt make the slightest bit of difference to my rough idle & no fault codes Em lights either, cat is fine, precat has been removed. Ecu has been reset a few times and for the first 5mins or so it idles properly but soon returns to it lumpy ways.

MarkGolf

Strange..

How do you reset the ECU on these, simply unplug?

I'm starting to think it could be to do with slack in the chain?

I did unplug the egr the other night and it did nothing.. Got a new pre cat fitted, new exhaust, new plugs, new oil (has beeen happening since oil change), weird!

Micro

I've just got back after giving my car a spanking up the road and to my suprise my car idles fine whilst coasting, same as markgolf's, hadn't took any notice of it before.

Reset your ecu by diconecting the main car battery for a few min's, if you have a standard fit radio you will need your code.

If you had a slack timing chain surely it would rattle like a pig, i too have thought maybe its the "timing chain", jumped tooth or something but i have no reason to think its at fault, no rattles whilst running or startup, i dont really want to spend out to have it done only to find it still rough idles.

i reckon i'l try a cts (coolent temp sensor) first, much cheaper part.

be really nice to get to the bottom of this, used to really annoy the hell out of me, i guess i just got used to it, but because of markgolf's post with what appears to be the same problem as mine, im all for finding a fix again.

MarkGolf

Is a strange prob!

I just did an oil change for a thickr oil and it's now quieter, was quite tappety before..

I just tried blanking the egr but no joy!

ahh I might just sell it as it stands 🙁

Micro

i just disconnected my cts/ets sensor and my engine idle is now perfect. The engine was allready hot when i disconnected it , it started straight away no problems. i am a bit worried about driving with the cts/ets unconnected, so i reconnected it and straight away my idle is lumpy again....

so looks like i need a new cts/ets sensor.

MarkGolf

Great, where is this sensor?

ecky1972

sensor is behind thermostat housing 2 pin plug same side as egr valve almost under the egr valve really just unscrews but will lose coolant so will need to be checked afterwards and would advise doing it when cold

kinglarry001

sounds like mine, but belive mine to be the tappets.

mine only idles rough after breaking heavily though. so dont think it is same problem.

MarkGolf

Mate, your a legend!!

Unplugged it and it wouldn't start, so plugged it back in then started the car and pulled the plug and bingo, perfect idle! I would have never guessed the collant temp sensor would relate to the idling of the car, how strange but nice one for the info!! Managed to spot where the exhaut blow I have is too when it wouldn't start! Woohoo!

kinglarry001

so when you unplug the cts, the car shouldnt start?

just unplugged mine (new one from few months back) and she started no problem, but the revs went straight to 2k, then slowly dropped down. (engine was warm though)

MarkGolf

Well, I don't know about 'shouldn't' start but mine certainly wouldn't start on the 2 occassions I unplugged the sensor and then tried to start....

My car was stone cold, not been started since Monday evening..

Really happy about the find, would have ended up selling it on for a few hundred quid cheaper with the rough idle!