Spark Plugs

Trying to track down a problem on the lads 1.0 corsa
the three pot twelve valve petrol version T Plate

Done all the things bought up by the Diagnostic

New idle air valve
New egr valve
Everything else seems to work fine nothing showing up on Diagnostic

Fuel pump seems to be working ok , fuel side of things looks good.

New cat and manifold so exhaust looks good.

However car starts to slow and revs cutback at about 50 mph
moreso up hill

engine light shows when this occurs and goes out if /declutch clutch
or drop revs a bit.

If revs kept constant , vehicle pulls uphill fine.

70 thou on clock


Now clutching at straws.

So 1 question
He changed plugs to these four pronged
pre factory set jobs
anyone had any bad experiences using these.

any other info gratefully recieved.

If you saw something similar posted a couple of months ago
its still same problem.
BTIA

 

i was going to say
there was a long threads on this a while back!
thought it was sorted!

how about as a test, put the old sparkies back in?

not got a dicky accelerator potentiometer has it?
(if it's the type with one fitted)

mike

 

If the MIL (malfunction indicator lamp) has been flashing, codes should be
stored in the ECU. Have you had the codes pulled recently? When was the fuel
filter changed? Are you certain there isn't a blockage in the exhaust?
The symptoms could be related to a whole mess of problems; those above are
the most likely, however there are a number of other possibilities.
If you are really struggling, I would suggest finding a Tech who has data
streaming capabilities with movie, and taking the car on a run until the
problem occurs. With such equipment, it shouldn't be too much of a problem
getting to the root cause.

 

[3]

[1]

Various bits snipped on above.
I think I would suggest that you have a blocked exhaust back box. as [1]
and [2] suggest.
[3] tells me that the exhaust rear of the cat has not been changed.
Dave

 

It sounds as if you have changed a lot of things but why?

I would normally check it on tech2 first to see what the stored codes are
and work from there.

With regards to plugs, buy genuine Vauxhall ones (they are cheap) and there
can be no question of incompatibility.

--

Alan


New & used Vauxhall cars & vans, servicing, repairs & parts
www.steeles.co.uk

Vauxhall CD players & handbooks
http://www.stores.ebay.co.uk/vauxhallradiosales

 

Thanks to all for their answers thus far.
Where the cat had been changed i found that they had cut off the new plug
and just
crimped and taped wires to the new cat wires .

These were all loose or falling out, however after sorting this out the
problem still persists
Cleaned all plugs.
they looked a nice light brown
Still no joy will try exhaust tommorow

The one constant thing in all this is that
when in tickover
Boot down hard produces a situation where the revs go up in absolute stages.
1k to 2 k then engine hunts for a bit 2k to 3k then hunts again 3k to 4
and so on.
If accelerator pressed slowly engine revs go up in a smooth manner.
The Canned History of this problem

It was checked on a diagnostic more than once by main dealers some 6 months
ago

At various different times they have,
via the diagnostic error codes,
put the problem down to cat,idle air valve and egr valve.

The work was all carried out by dealers in kent.

The problem still persist.

However tried ringing my local (Cornwall) vauxhall dealer today

asked for a price to have it put on a diagnostic
was informed this would be about £30.00 inc vat ( reasonable )
but was then told the following -:

A Diagnostic would only show last error and whatever it showed it may not be
that part that is faulty, because a diagnostic will only show in what area
to search for the problem.

I then said that according to the manual,
the error values reset at every tenth start
so therefore there should be one in 10 chance of showing the last ten error
codes.

No says he,it would only show the last error.

He than said
What people normally do is bring it to us and we will investigate and put it
right.

As my son has spent a bloody fortune on this car already and got nowhere
with other so called 'Main dealers ' handling the job.

I am very unwilling to let anyone take yet more money.

Is there any other way i can
a- read any errors myself
b - get someone other than a main dealer to give me a 'proper' reading.

(Ps My own old car has a Distributer and points with No Electronic EMS as
such HooBloodyRahhhh )

 

I would be interested to know the rate of crosscounts from the oxygen
sensor. Usually there are approx. 6 per 10-seconds, that's to say that the
sensor should rise and fall passed the 500mv point 6 up and 6 down every
10-seconds. This can be checked with a dc volt meter on the signal wire of
the sensor. Poor sensor response WILL cause stepping in the rpm range, but
test the sensor before replacing.

 

Forgot to include that this test should be performed at approx. 2500rpm.

 

Cheers again

I will sign on and let you know progress late tommorrow night

 

You have no obligation to let them do any repairs. I think it is still worth
getting them to do a Tech2 test and report all trouble codes and then give
you a written estimate for the repairs.

This will then give you details of the codes and also the recommended work.

You can then make a decision whether to get them to do the repairs or do
them yourself.

--

Alan


New & used Vauxhall cars & vans, servicing, repairs & parts
www.steeles.co.uk

Vauxhall CD players & handbooks
http://www.stores.ebay.co.uk/vauxhallradiosales

 

Hi,
Symptoms you describe seem to me, to suggest Mass Air Flow sensor.
I have changed literally hundreds of these for the same symptoms as
above.
Find a mate with a 1.0 ltr or a 1.2ltr 4 cyl. They are the same
part numbers I believe. Swap them over and test the car.
The Tech 2 test usually does'nt show up this fault and, can throw
up some red herrings. E.G. Lambda sensor,and is due to a rich mixture(
or so it thinks)due to low flow readings and throttle position sensor
readings being to high for MAF values.
Hope this helps
Bilko130 (Ex Vx Tech)

 

Following some instructions received
I removed MAF plug
(Mass Air Flow sensor)

Immediate improvement in drive.
No pull back when pulling up hill etc.etc.
still a bit poor in low pulling away
otherwise 1000 percent improved ( Must Be The MAF)



so you along with another op do appear to be correct Bilko

Only problem now is
1
where do i get a cheap one they are priced at
wait for it
£234.00 +vat ( for a piece of what ?)

2
Is there a way to test the existing one ( lot of money wasted if i'm wrong)

3
Is it possible to repair the one i have If not why not.

 

Capstick's diagnosis was sensible and logical and appears to be the correct
one. The question is, why have you paid for so many other parts as part of a
trial and error replacement process?

Diagnosis beats experimenting every time.

--

Alan


New & used Vauxhall cars & vans, servicing, repairs & parts
www.steeles.co.uk

 

Well alan
The rest of the thread did say, that following diagnosis by main dealer
(Vauxhall)

on there advice, all the parts were on various different occassions, fitted
and charged for by them.

Another poster pointed out that the Diagnostic does not show a MAF error

So that was why all the other parts were fitted.
In other words the main dealer tossers only saught to line their pockets.

But i swear to god they will rue the day that i came into possesion of a car
whose parts are priced using what can only be described as legalised fraud.

Before i am finished i will be making my own electronic parts rather than
pay their Exhorbitant prices.

I shall post an explanation later on how to get a MAF Sensor for at least
£115.00
cheaper than main dealer.

 

Alan,
I Disagree. As you are "Vx Involved" you must agree there are
times when you simply must change a component because, you suspect
this to be the problem.
Even Vx tech info are advocates of this approach. And, with a
case no. will pay for R+I x2
I personally, only found this fault by subsitution and then,
thorough diagnosis as to why.
I wonder how many Lambda sensors have been changed (to no avail)
to try and rectify this fault?
Regards
Bilko130

P.S. How are things in the Vx world?

 

Mass Air Flow Sensor from main dealer (Maynes Garage RedRuth) was £264+vat
When ringing local Mill Auto Supplies( Edmunds Walker As Was)
they initially said it was a Main Dealer part.
However i took the part into them and showed them the Bosch Part No
One phonecall later by them to their Bosch Supplier.
Mass Air Flow Sensor From Mill Auto = £165.00+Vat
This is a saving of roughly £115.00 once vat is added to both prices
I then tried this at a local AutoSpark Place
Cornish Electro Diesel ( CED )
they were £160+VAT another £5.00 + vat Saving

But the best was that after some ringing round
I found a second hand spare.
from a breaker
for the Princely Sum Of
£10.00 + VAT ( I dont yet if it works will let all know Tommorow)
If It Does You Should be able to see my grin in the Outer Hebrides.
Thanks to all for their Advice So Far.

 

Well done on finding the s/hand unit. I hope it works. I hadn't realised the
pricing anomaly with the Bosch part. I will take this up with vauxhall.

--

Alan


New & used Vauxhall cars & vans, servicing, repairs & parts
www.steeles.co.uk

 

try them on lambda sensors too, while you are at it

 

Did you see me Grin

No where in any manual i have read does it say clean the MAF as a part of
servicing or troubleshooting for that matter
Haynes fails again

So if you find your car acting up something rotten and your getting nowhere
with it try unplugging the MAF and running the car.
if you see a marked impriovement in performance then clean The Maf


The new (second hand part) has transformed the car to what it was six months
ago.
I believe because of the failure of the MAF its had
New EGR valve ,New Air Inlet Valve and New Plugs.

It may also have been responsible for having to have a new Cat because of
failed emissions test. (not sure on this one)

I have since discovered that all i really had to do was very carefully spray
clean the MAF with carb cleaner and i would not have needed the new (second
hand) part either.

Before i asked on the Ngs i knew very little about Engine Management
Systems.
Their affect on the performance of an engine, should the peripherals of the
system break down or become clogged etc .

I am through these NGs a lot wiser now and i thank all here.

I have made sure to finish off this thread so it makes it intact to the
Archives for the future use of some other budding Amateur Mechanic.

I would also add this link that was so useful and explanatory
It just goes to show that it doesn't necessarily have to be the same model
of car
just to get an answer to what you are looking for.
How to clean your MAF
http://www.fordscorpio.co.uk/cleanmaf.htm


Finally special thanks to TIM for advising removal of MAF to test this for
fault in first place.