205 Engine Light On, Running Rich and Smoking

[saltyanger]

Morning all, had a quick search on here first and can't find a similar post. So here's the problem with my 1.9 205 GTI (Series 2):

• Since I’ve had the car it has pinged when hot, low revs under load.
• Pinging has improved a lot by doing the following over the last 18 months:
  • New oxygen sensor
  • Ignition module (although this may not have affected the pinging much, I think it was just changed out to see what effect it had)
  • New leads and plugs
  • New fuel filter
  • New breather hoses
  • New air intake hoses and air filter
  • New coolant temp sensor
  • Replaced the hose from the fuel vapour canister to the throttle body which had a slight air leak (could hear it hissing as you moved the hose)
  • I always run it on 98 unleaded
  • It’s also had a radiator re-core and new hoses – tends to run a bit cooler now on the gauge.
• The last job done was the fuel vapour hose to throttle body and this had a noticeable improvement on the pinging in that it hardly does it now (only when you give it enough throttle under load at low revs). However it now seems to be running richer as it now smokes when idling and driving. It only used to smoke a bit when you revved it enough.
• It doesn’t seem to burn oil or water and it doesn’t smoke when you start up, so I’m thinking this is not gaskets, gas rings or valve stem seals.
• Compression is high. Alpine Affaire did a test and said it's at 120 psi. Don't know why cos its unmodified.
• I’m thinking it running richer might be due to fixing these various parasitic air leaks and now the mix ratio is higher in fuel than air. This makes me think maybe the Air Flow Meter is telling the computer there’s more air coming in than there really is – does this happen? Can the AFM be re-calibrated?
• Nowhere I’ve been to yet has the kit to plug into the ECU and read off the engine fault code. Does anyone know a garage in Melbourne that can do this? I've been to a Bosch Service Centre but they haven't got the plug for it either.
• I can’t think of what else might be making it run rich because it should be self-trimming.
• One thing I wondered is that I ran a tank of injector cleaner through it recently and was wondering if the exhaust from this might have fouled up the oxygen sensor. Has anyone seen this happen?

I'm booked into Automotive Practitioner EFI specialist next week to take a look, but would like to fix myself first if possible.

Thanks
Tim

 

[Bluey]

You need a 1.5m piece of wire to pull 205 fault codes. Google how to extract them. Plenty of threads & resources

Would help too if you were more specific than 'Australia' as your location so that AFers can recommend someone competent for you.

 

[PeterT]

If it's a series 2, it will have Jetronic injection and still use the distributor for base ignition timing. Once you've confirmed that, check the base timing is set at 10 deg BTDC.

120 psi is pretty poor for any internal combustion engine. It should be more like 185psi.

 

[saltyanger]

Yep it's on the metal inlet not the plastic one so I understand that's Phase 2? Its a 1992.

OK will ask the EFI guy to check out the timing and see if he can extract the fault code. I'm based in Melbourne, in case you know of someone knowledgeable with these cars?

I think it might have been 220 psi then. He def said it was higher than normal.

 

[IWS]

I'm based in Melbourne, in case you know of someone knowledgeable with these cars?

There is a "sticky" thread here with details of mechanics in Melbourne who are familiar with French cars. Pick one that you like the look of and call them up to ask if they are familiar with your model of car.

Ian.

 

[james h]

One thing to check off also, douse the afm connecting plug with contact clener and the o2 sensor connectors under the expansion tank while your at it. Then douse again for good measure. Bloody things!

 

[PeterT]

Cam timing incorrect? If advanced too much it will increase combustion pressures. A '92 model would be a series 3. ie DKZ engine with MOtronic ECU, disc brakes on the rear etc. Early S3 have an aluminium inlet manifold, later S3 are plastic.