Car running really rough

canhefixit

Car is a 05 astra 1.4 and is running very rough and can be hard to start, when driving it at speed it's fine but when you come to a stop sometimes the revs will drop an it will stop
When starting first thing in morning it can be hard to get going and it is very underpowered as well until you get it going
Put in new plugs and air filter still no difference and there isn't any eml on dash
Anyone have any ideas what might be up?

Foxhole Norman

Check your ignition coils/MAF sensor. Get it hooked up to diagnostics as well!

Special Circumstances

This has been giving you a lot of trouble hasn't it? What's been done lately?
Coils, leads, plugs, vacuum leaks and other causes can all cause rough running.

canhefixit

Foxhole Norman wrote: »

Check your ignition coils/MAF sensor. Get it hooked up to diagnostics as well!

This car Dosent have coils it's a whole ignition module which does appear to be working as it driving once I get it going ya know, how can I test the maf sensor if it's working? I scanned it and no codes are stored on it either

canhefixit

Special Circumstances wrote: »

This has been giving you a lot of trouble hasn't it? What's been done lately?
Coils, leads, plugs, vacuum leaks and other causes can all cause rough running.

It has yeah you must remember my previous thread on it
I fully serviced it new plugs, air filter, oil an filter, battery etc
I've double checked for leaks and there's none either, it's when idel it wants to turn off and when getting going it hesitates a lot before building up any revs but once driving it at speed it's fine although I've noticed it isn't at full power either when driving it

Foxhole Norman

canhefixit wrote: »

This car Dosent have coils it's a whole ignition module which does appear to be working as it driving once I get it going ya know, how can I test the maf sensor if it's working? I scanned it and no codes are stored on it either

Not sure if modules/coils work the same but if a coil is out it'll cause a misfire and the engine will be rough, maybe a part of the module is gone?

rex-x

Foxhole Norman wrote: »

Not sure if modules/coils work the same but if a coil is out it'll cause a misfire and the engine will be rough, maybe a part of the module is gone?

A module is just 4 coils held together by plastic basically, €€€€ for the manufacturer but one can fail and leave 3 good ones.

Foxhole Norman

rex-x wrote: »

A module is just 4 coils held together by plastic basically, €€€€ for the manufacturer but one can fail and leave 3 good ones.

Grand, so it could well be the coils. Get that yoke on diagnostics!

canhefixit

Ok lads I switched the module with another from a mates car and no diff with it but I did put in a new air flow meter and it has made it a little better I think but it's still hesitat when reving/taking off
I scanned it again even though no eml and nothing stored at all
It so bloody annoying at this stage

Muckie

Had you tried cleaning out the inside of throttle body.

Sometimes carbon build ups.

Had similar issue on the wifes 03 Yaris.

Took off the air filter and housing, used some throttle body cleaner, (not too much, few squirts) then taking it easy with a cloth and some swaps, cleaned it out.

Be amazed how much build up they get, car ran rough for a bit, now running 100%.

Good luck.

Dord

Muckie wrote: »

Had you tried cleaning out the inside of throttle body.

Sometimes carbon build ups.

Had similar issue on the wifes 03 Yaris.

Took off the air filter and housing, used some throttle body cleaner, (not too much, few squirts) then taking it easy with a cloth and some swaps, cleaned it out.

Be amazed how much build up they get, car ran rough for a bit, now running 100%.

Good luck.

My old Merc A class had the same symptoms as the OP and it was just a clogged throttle body. It would cut out at traffic lights, etc.

9935452

canhefixit wrote: »

Car is a 05 astra 1.4 and is running very rough and can be hard to start, when driving it at speed it's fine but when you come to a stop sometimes the revs will drop an it will stop
When starting first thing in morning it can be hard to get going and it is very underpowered as well until you get it going
Put in new plugs and air filter still no difference and there isn't any eml on dash
Anyone have any ideas what might be up?

Id be saying the same as the other lads here . ignition coils first guess.
MAF sensor. Try disconnection the MAF and see if there is a difference.
Thirdly are the spark plugs you put in the correct ones. Dont assume the ones you took out are correct eithre, check online/manuals

canhefixit

Cheers for the help lads
I have cleaned the whole throttle body I cleaned it all up when I changed the maf sensor didn't make any diff
I swapped ignition module from another astra just to try and no diff
The plugs I got I checked and they or correct ones
There no vacuum leaks, I replaced air filter too, there is no eml at all stored it has me confused to say the least

nd

Try cleaning the idle air control valve, or unplugging it to see if it makes a dif.

9935452

EGR valve maybe??

canhefixit

Just to follow up on this issue

I had replaced the maf with a genuine Opel one, fully serviced car, new plugs, swooped ignition module and 02 sensors and all to no avail
Me and a mate couldn't understand what else it could be with no lights on the dash and not a thing we were doing was helping while the whole time gettin worse to being u drivable
Until we swapped over the mafs again from another car and hey presto car going like a dream again
Turn out the gen maf from Opel was faultly so returned it and in the mean time bout a 2nd hand one and car now perfect