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[relluf]

Hi
Occasionally our 2.2 will not start properly, very rough idle ,hunting and shaking then all of a sudden everything back to normal.
Seems to be worse when you try to start shortly after stopping/switching off ie fuel station nip into shop etc.
So today ,new plugs, cleaned breathers and throttle body etc as per guide.
Doesn't seem to have fixed the issue
So what should i look at next?
It is lpg and doesn't make any difference if its cold ,warm or at temp and when it sorts itself out it runs like a dream on petrol and on gas.

Any ideas? All input gratefully received!!

[tunnie]

Get a code reader on it, could be the coil pack starting to fail.

But need codes really, as cam sensor could be causing issues. As when that was failing it was the only time I had hot starting issues 

[relluf]

Get a code reader on it, could be the coil pack starting to fail.

But need codes really, as cam sensor could be causing issues. As when that was failing it was the only time I had hot starting issues 

Thanks Tunnie
Cam sensor? could be I guess,but it runs fine most of the time.
I dont think anyone round here has a reader 
Best put my name down for Newent!!

[tunnie]

Get a code reader on it, could be the coil pack starting to fail.

But need codes really, as cam sensor could be causing issues. As when that was failing it was the only time I had hot starting issues 

Thanks Tunnie
Cam sensor? could be I guess,but it runs fine most of the time.
I dont think anyone round here has a reader 
Best put my name down for Newent!!

Be worth investing in a cheapie 

I've got a Bluetooth one that uses an app on my phone to get the codes 

[Jimbob]

I'm in Saltney if you want codes checking

[relluf]

I'm in Saltney if you want codes checking

Thanks for that Jimbob, may well be in touch and get you to read codes at least then I know what is causing it.

[Jimbob]

Had a look at this one last night.

fault code that kept occuring was p0170 - rich Exhaust.

Snapshots of data, plus live data here:
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdsnap.csv
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdfc.txt
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdld1.csv  (car cut out for last few seconds of this one)
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdld2.csv

Unplugged Maf, no differnce.
Knock sensor data concerns me.
Not sure if there are benefits to blanking egr on 2.2?

Had a fair poke around, and also found an airleak around the throttlebody, which obviously needs fixing first.
I still wouldnt rule out the Cam sensor too, as they can cause strange effects on the 2.2.

Bizarrely my code reader wouldnt communicate once running on gas, only petrol.
Running was very similar on both fuels.
Had it been petrol only, would sugest injector cleaner and a thrash...but dont think theres any value as symptons persist on both fuels.

[relluf]

Had a look at this one last night.

fault code that kept occuring was p0170 - rich Exhaust.

Snapshots of data, plus live data here:
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdsnap.csv
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdfc.txt
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdld1.csv  (car cut out for last few seconds of this one)
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdld2.csv

Unplugged Maf, no differnce.
Knock sensor data concerns me.
Not sure if there are benefits to blanking egr on 2.2?

Had a fair poke around, and also found an airleak around the throttlebody, which obviously needs fixing first.
I still wouldnt rule out the Cam sensor too, as they can cause strange effects on the 2.2.

Bizarrely my code reader wouldnt communicate once running on gas, only petrol.
Running was very similar on both fuels.
Had it been petrol only, would sugest injector cleaner and a thrash...but dont think theres any value as symptons persist on both fuels.

Thanks for taking the time and effort to help out James, good to meet you again.
I have not had chance to try and seal the throttle body yet ,but fairly certain that will improve things.


As a general explanation,where the lpg system plumbs onto the top of the throttle body it should be held with three grub screws (only two at moment) and suspect that the seal inside is probably failing,so drawing in unmetered air straight into body.
I don't think I will be able to get replacement seal as system is ancient,so any ideas how else best to seal to top of the body with?

[4x4]

Try rtv sealant 

[relluf]

Try rtv sealant 

Ha thanks ,just googled it see what you mean!!
I wont use glazing silicone like I was going to then

[SIR Philbutt]

Jimbob

My reading of those shows O2 loop open (should be closed) all the time making SHORTFT1 remain at 0% (should fluctuate +ve -ve). IME it seems to then operate under a standard MAP so all other fuel trim data can't be trusted.

Also MAF reading is high, normally 10-12 kg/h at tickover
And Knock control should be inactive at tickover

Not all faults make the spanner light come on straight away, so you might think that it is clear and something else is making O2 loop open

Does it start judder when codes cleared and then settles before you can get a read of live data ?

So is it the air leak, probably, we'll see 
or MAF, could be 
or knock sensor , probably not, just active because of miss fire/juddering

HTH   

edit: only benefit to blanking EGR is to test if it's permanently open as this causes miss fire like an air leak

[relluf]

Jimbob

My reading of those shows O2 loop open (should be closed) all the time making SHORTFT1 remain at 0% (should fluctuate +ve -ve). IME it seems to then operate under a standard MAP so all other fuel trim data can't be trusted.

Also MAF reading is high, normally 10-12 kg/h at tickover
And Knock control should be inactive at tickover

Not all faults make the spanner light come on straight away, so you might think that it is clear and something else is making O2 loop open

Does it start judder when codes cleared and then settles before you can get a read of live data ?

So is it the air leak, probably, we'll see 
or MAF, could be 
or knock sensor , probably not, just active because of miss fire/juddering

HTH   

edit: only benefit to blanking EGR is to test if it's permanently open as this causes miss fire like an air leak

Just been out having a play ,took all gubbins of top of throttle body, pulled out large sealing "o" ring cleaned it all up ,replaced ,found a suitable extra grub screw and put it all back together,which seems to have cured the air leak.

And now it idles smoothly and I cant get it to repeat the rough running.
So was that it (air leak)? Maybe lets hope so watch this space.
Thanks once again everyone.

[Jimbob]

Sounds good. If you want another data snapshot to compare let me know

[Jimbob]

Saw this again tonight.

Now running perfectly when on gas, but not so clever on petrol, so the air leak has helped, but not fully resolved.

Current snapshot
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdsnap3.csv

And Old and New data together

http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdsnapcompare.csv

It is clearly still knocking.  Given its LPG and therefore doesnt use much petrol, I wonder if the injectors are not as clear as they should me.  Is there pehaps some mileage in half a tank of vpower and injector cleaner, and ragging it on petrol for a 100 miles or so?

[SIR Philbutt]

Saw this again tonight.

Now running perfectly when on gas, but not so clever on petrol, so the air leak has helped, but not fully resolved.

Current snapshot
http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdsnap3.csv

And Old and New data together

http://images.omegaowners.com/images/Jimbob/hosted_for_others/fdsnapcompare.csv

It is clearly still knocking.  Given its LPG and therefore doesnt use much petrol, I wonder if the injectors are not as clear as they should me.  Is there pehaps some mileage in half a tank of vpower and injector cleaner, and ragging it on petrol for a 100 miles or so?

Assume that snapshot is on petrol. Did you see if when on LPG the knock was inactive? just to know the sensor is OK
O2 loop is still Open and should be Closed, so it is seeing something wrong somewhere, although with RPM not down to desired could still be in warm up phase when loop is open.

LONGFT1 is not available in both snapshots BUT if this is high it could be trying too hard to get this down (sensor1 lean) and causing the rough idle. LPG ECU appears to ignore LONGFT1 at idle on mine AFAICT

As you suggest a run on petrol would be good, just to let the fuel trims reset after all the rough running. Maybe with some injector cleaner or VPower if this makes no difference
LPG should always operate correctly if petrol is, but sometimes despite it, IME