Corsa 1.0 - lack of power

[stuartinlancashire]

My better half is having problems with her 1.0 12V Corsa on a T plate.

At low revs the car is ok, but when the revs exceed 2500rpm the power drops off, if you are driving and hit an incline the power drops, then the amber engine management light comes on, ease off the throttle and the light goes out.

I have replaced the air idle valve with a brand new one over the weekend as I understood this may be the likely culprit for this type of issue, however this has only made a slight improvement. The plugs have also been changed (problem existed before the plug change). and the air filter is fairly clean.

Does anyone have any ideas what may be causing this? I hope someone could come up with something as it's driving her crazy!

 

[davieboy]

best bet is to get it checked out by a decent autoelectrician. a probable culprit is the MAF (Mass Air Flow) sensor. quite expensive to buy new, easy to test with the correct diag equipment plugged in, so a wee bit difficult to confirm over t'internet

seriously, a decent, independant, autospark should be able to tell you whats wrong quite cheaply.

 

[stuartinlancashire]

Just an update for those who are insterested, took the car in to an independent garage to get it hooked up to a computer, cost £10. Two fault codes where logged, mass air flow meter & lamba (is that the right spelling ) sensor, garage cleared the faults and they did not come back (until we left that is, then the bloody light flashed on again).

I have cleaned the connections on the MAFM with WD40 in case they where dirty but this has not made any difference.

Rather than shelling out to have both done by the garage, my girlfreind has asked a friend (who is a mechanic but just repairs and services cars as a hobby type thing) to replace the MAFM first, and then if there is still a problem the lamba sensor will be done also, and at a considerably lower cost than the garage quoted

 

[^neo^]

Id go for the lambda sensor first, cheapest and easiest option! Should be no more than £15 and a 10 minute job to fit

 

[ashleygtir]

had the same prob with a similer corsa also 1.0ltr 12v, firstly it had an idle fault, checked fot codes code was an idle air control valve, replaced it and a modified loom, week later light comes back on, only code was Lambda sensor, cleared code and it never came back on but the car had no power after 2500 rpm and if you floored the throttle it would hold back, list of parts tried.......
MAF sensor
Cat
Lambda sensor
Fuel filter and plugs
and a timing chain with tensioner and guides but problem was still there sp only one last thing to try.........................ECU.
fitted 1 and it cured the fault. still not sure how it went from an idle fault to an ECU. hope this helps in some way

 

[sm1thson]

I have cleaned the connections on the MAFM with WD40 in case they where dirty but this has not made any difference.

i would clean it with brake/ carb cleaner / isopropanol or at least meths, wd40 leaves a film that dust etc sticks to

 

[erictheking]

had similar problem with my car, the catalyst convertor had failed...probably would have been picked up on...but common on your type of car at this age!

 

[stuartinlancashire]

Good news, MAFM was replaced and car is running alot better.

Bad news, car was left to sand for the best part of a week after the work was done, it drives ok but has now developed a loud ticking noise and a smell like the brakes are binding or the clutch is slipping.

It has been into a garage and the verdict is that the camshaft is FUBAR'd!

I think this motor is defo a lemon, and my gf is well p'd off!

 

[stuartinlancashire]

Another update on this car, the "ticking" problem has been solved, two garages (one of them a Vauxhall dealer) said they would need to strip down the engine to find the cause of the problem.

A friend of my girlfriend had a look at the car, he took the rocker cover off and found that the noise was being made by a loose jockey wheel on the cam chain, tightened it up and it is now running nicely again.

 

[johncorsa]

I wonder stuartinlancashire (or any other reader) can you give me some info. Our corsa is the same 3-cyl on a T plate, same running problem.

1..MAF Sensor...where is this located, what does it look like?
2..Lambda Sensor...is this screwed into the catalist converter?
3..Idle Air Control Valve....where is that? (think i changed that 1 yr ago).
4..Somebody mentioned mods to the Loom of item 3 (any comment welcome).

Wonder if you could give me an idea of the cost price for these parts. If you have the vauxall part codes, it would be nice to have them.....sometimes its possible to get a discount on the price if you are able to give the code (ring a few dealers, give the part-code, ask for a 15% discount..if you see what i mean).

Thanks........john

 

[stuartinlancashire]

I am no expert, but I will try to help:

1..MAF Sensor...where is this located, what does it look like?
This is located on the section of plastic pipe on that runs from the air filter to the engine on the drivers side of the engine, it is held in place by two retaining clips and has a cable plugged into the front of it.

2..Lambda Sensor...is this screwed into the catalist converter?
I beleive this is in the manifold just behind the radiator.

3..Idle Air Control Valve....where is that? (think i changed that 1 yr ago).
It is on the side of the throttle body, its a sort of rectangular shaped thing held in place by three bolts (i think) and it has a springed plunger on it that pushes against the throttle mechanism.

4..Somebody mentioned mods to the Loom of item 3 (any comment welcome).
Can't help with this one.

Could not help with part numbers but the probably have the numbers stamped on them, I would suggest you try a motor factor as they may be cheaper than a main dealer.

 

[johncorsa]

Thanks Stuart..very hepfull.
I assume yours is okay now?
I assume your problem (rough running), was due mainly to the MAF Sensor?

If anyone else can offer information, it would be appreciated!

thanks again...........john

 

[stuartinlancashire]

Yes, replacing the MAF solved the poor running problems, and the engine noise was caused by loose running gear on the timing chain.

The only problem we have now is not a major one, but we find that the idle speed sometimes dips to about 400rpm then picks back up to 750rpm after a seccond or so, I think this is probably caused by the ECU not being reset after the MAF and air idle sensors where replaced, any comments on this would be welcomed.

 

[johncorsa]

I dont know too much, but i am aware that these cars (at least the early ones) require a software upgrade after the air idle valve has been replaced. This has to be done at main agents.

When i renewed the air idle valve ages ago I didn`t bother to update the software and i never had the semi-stall problem.

Come to think of it, 2 months ago i had fault codes read and this pointed to another sensor so-far not mentioned. I think it may have been a crankshaft speed sensor (mounted under the sump area). Could this be a possible cause of semi-stalling?....if the sensor had a periodic fault it would give a bad signal to the ECU.

thanks.......john

 

[jonnyfishing]

The short answer is yes,the crank sensor can send erratic signals especialy when it gets warm/hot.

I think you also have a cam shaft position sensor that can cause the same problems if it's faulty.