Corsa C running lean and rough

[asylum119]

Make: Opel
Model: XC
Engine: size/Type 1.4/z14xep
Year: 2005
Mileage: 130***

My corsa lately lost power and blew black smoke and the emissions light came on, So far I have changed the spark plugs, coil pack and o2 sensor which seemed to help (no black smoke or emissions light any more) also I had the cat replaced 3 months ago with a new one prior to these symptoms.

But it sadly is not fixed, No warning lights are on and the car sputters at about 3000rpm with no load, if I accelerate heavily then it seems to stop and give me power until it is at a cruising speed and the car jerks so much it almost wants to stop.

diagnostics show the car running lean.
Diagnostics also showed cylinder 2,3 and 4 missing which was the reason for replacing the coil pack. Further diagnostics didn't show cylinders missing but the car was running ok

I cant find an auto electrician or mechanic that can diagnose the problem and I know that the dealer is going to cost me a mint. So I thought that I would bring it to this forum... which I like and hopefully can become an active member.

Any advice welcome because I will just be sitting here stressing

Thanks

Brett

 

[Mursal]

Air mass meter or MAP sensor faulty or partially clogged.

Clean using carburettor cleaner.

Just be careful not to damage when cleaning.

 

[Burnerman]

I agree, and stick a new air and fuel filter in, just for good measure.
John

 

[asylum119]

Thanks for the response I shall give that a go and post back the results

 

[asylum119]

I have replaced the fuel filter, air filter and cleaned the MAF with carb cleaner, Also figured out the pedal test to get error codes.

After reseting the fault codes and taking the car for a drive I still receive a MAF error and drivability is only slightly better so it will have to be replaced before I can determine If this is the only problem.

On a funny note the car dealer Robina Holden wanted to charge $1500 for a new Bosh MAF that they did not even have in stock !!!!

I have ordered a brand new Bosh MAF from Germany and it cost me $130 by the time postage was covered and it was converted to EURO and a chinese version would have been even cheaper again

 

[asylum119]

Thought I would update to reflect my current situation.

After replacing the MAF the car is at least drivable (vast improvement), However Now I am getting an o2 sensor error which I find strange because the EML does not display a fault.

Cylinder 1, 2, 3 are still missing which is noticeable at idle, and whilst driving the occasional shudder proves very annoying and dangerous.

I really dont wish to replace the pre cat o2 sensor to find out that it did not need replacing.

Would a faulty o2 sensor cause cylinders 1, 2, 3 to miss ?

 

[jetex]

If you were able to pull off one plug lead while the engine was running, this would put your O2 sensor outside it's parameters causing the M.I.L light to come on, but this could lead you to think that it's a sensor fault (do you understand what I'm getting at ?? - you're looking at the consequences, not the cause). I suspect that you may have a fault with your EGR valve ? Is your engine the small 4 cylinder 8 valve, or the 16 valve ?? To test your MAF sensor, all you need to do is disconnect it, let the ECU default, and see how the car drives.

 

[asylum119]

I suspect that you may have a fault with your EGR valve ? Is your engine the small 4 cylinder 8 valve, or the 16 valve ??

Clearly did not read OP but

^ was helpful

I have replaced the o2 pre cat sensor and now have no errors stored.

I have the 4cyl 16 valve, engine: z14xep

After a lot of research I also suspect the EGR valve and will be cleaning it in the next couple of days.