Fun pickup high emissions

[mexmeister]

My Fun (1.6 AEE) has been running pretty poorly for quite some time, but recently I noticed that there was an excess of grey/white smoke constantly coming from the exhaust, even when the engine was up to temp.  It appeared that the engine was running rich, so I checked the spark plugs to see what they looked like (only done about 1500 miles) and they were pretty crudded up (see photo ).   A local garage checked the emissions and the CO2 reading was about 8.0%.  I gather to pass the MOT (next month) it has to be 0.3% so it looks like I have a problem.  They ran a quick diagnostic check and the following came up:

00519 -  Intake Manifold Pressure Sensor (G71) - 27-10 -  Implausible Signal - Intermittent

01251 -  Fuel Injector for Cylinder 3 (N32) - 31-10 -  Open or Short to Ground - Intermittent

There was also a code relating to a coil pack problem (sorry - I've lost the detailed info on this)

When they cleared the fault codes and then checked again the only problem that remained was the one with the coil pack.   It gather that a failing coil pack can cause emission problems, but do you think it could be causing my problem?  A bit of history -  I had a head gasket failure last year which was sorted (including head skim) but since that was done, the engine has pinked quite badly, particularly under load.  I've been adding an octane booster to the fuel which pretty much eliminates the pinking, (and maybe explains the condition of the plugs!).  However, I'm wondering if maybe the head has been skimmed previously which has now resulted in the compression being too high.   The head gasket still seems OK as I'm not losing any coolant.  The engine consumes quite a bit of oil (I gather not that unusual) but it's only recently that the problem with excessive exhaust smoke has appeared.   Engine has done approx 80K miles - Most journeys are relatively short - not much long distance driving. 

Any comment would be much appreciated.  I'm not used to these modern cars with fuel injection etc.  I'm more used to cars with twin 40s - easy to work on!

Thanks
 

[RicardoM]

From your description and by the look of the spark plugs I'd say it is a clear case of incomplete combustion from bad ignition timing.

 

What type of spark plugs (make/code) are you using?

[mexmeister]

Hi Ricardo - cheers for that.   The plugs are Bosch WR78X.    I've got a new Bosch coil pack on order - do you think this is likely to resolve the issue?   Also do you think the pinking is likely to be related to the coil pack problem?

Thanks

[KenONeill]

@mexmeister - From the photo alone I'd agree with @RicardoM about the poor combustion caused by bad timing.

 

A new coil pack will give you a healthy voltage at the plugs, but it won't cure pre-ignition (pinking) in every case. The root cause of this is always the mixture starting to burn too early in the compression stroke of the engine.

[RicardoM]

16 hours ago, mexmeister said:

I've got a new Bosch coil pack on order - do you think this is likely to resolve the issue?   Also do you think the pinking is likely to be related to the coil pack problem?

Since you didn't remember the exact error code about the coil pack, I can't say for certain if the coil pack itself is the issue. That is why I always try to find evidence of fault before buying parts.

The pinking is not related to coil pack. There are many possible causes such as:

• faulty knock sensor
• carbon deposits on top of the pistons or on spark plugs
• bad ignition timing setup
• faulty distributor
• too high compression ratio (cylinder head overskimmed)

When started the pinking? Right after the head gasket job?

[mexmeister]

Thanks for the comments guys.  It will be interesting to see if the new coil pack helps.  I seem to remember the pinking starting around the time that the head was skimmed, but I can be sure if it was at exactly the same time.  I'll check out the distributor cap and rotor arm etc, to see what they look like.   Am I correct in thinking the ECU auto adjusts the timing on the 1.6 engine and that you can't do it by manually adjusting the distributor? 

 

Cheers

[mexmeister]

One other point to mention - but I guess probably not be related - the engine always tend to run pretty cold.  In summer the temp gauge needle only gets up to about the 1st line (about 1/8th) and over the winter, hardly moves at all from the bottom.  If I sit in traffic for 5-10 minutes it then goes up close to 3/4 before fan switches in.  A new radiator, coolant temp sensor and thermostat was fitted last year.

[RicardoM]

1 hour ago, mexmeister said:

Am I correct in thinking the ECU auto adjusts the timing on the 1.6 engine and that you can't do it by manually adjusting the distributor? 

Yes, you are but the setting of the distributor significantly influences
the ignition timing.

 

1 hour ago, mexmeister said:

In summer the temp gauge needle only gets up to about the 1st line (about 1/8th) and over the winter, hardly moves at all from the bottom.  If I sit in traffic for 5-10 minutes it then goes up close to 3/4 before fan switches in.  A new radiator, coolant temp sensor and thermostat was fitted last year.

I have uploaded a photo of the temperature gauge. I've drawn extra markings and labels to help you pinpoint the temperature instead of using fractions of the scale. Please rephrase your comment using Celsius degrees. It will be easier for me to give you a solution.

[mexmeister]

So you think it would be worth adjusting the timing manually to see if this helps?   I have go a timing light somewhere.
Thanks for the picture of the temp gauge - My Fun's gauge doesn't show any temperatures, it just has lines.   When driving at normal speed, in the summer the needle only gets to about 70 and in the winter it pretty much stays on the bottom stop (60).  It only goes up significantly in slow moving traffic.
Cheers

[KenONeill]

12 hours ago, mexmeister said:

Thanks for the comments guys.  It will be interesting to see if the new coil pack helps.  I seem to remember the pinking starting around the time that the head was skimmed, but I can be sure if it was at exactly the same time.  I'll check out the distributor cap and rotor arm etc, to see what they look like.   Am I correct in thinking the ECU auto adjusts the timing on the 1.6 engine and that you can't do it by manually adjusting the distributor? 

 

Cheers

Also @RicardoM - OK, so how much was the head skimmed? When you skim the head, unless you machine out the combustion chambers, you increase the engine compression ratio, which means that you need more advance to prevent pre-ignition. Presuming the head and piston crowns were properly decoked at this time, we can at least rule out hot spots as a cause for this.

 

Also, I'd expect to see a water temperature ~90C in normal running. There's a reason for asking these questions:-

1. What is the heater like?
2. Do the radiator hoses get hot when you're seeing your temp needle going off the stop?

[mexmeister]

I've been able to access the pickup using VCDS-Lite and I noticed that the value for coolant temperature seems to drop by 50 degree a few seconds after being accessed (see photo).   I guess this means a faulty temp sensor?   The heater seems to be pretty good (wife likes it!).  Just ran a check with engine running whilst stationary and when the temp gauge needle starts to move off bottom stop, only front/top hose is getting warm.  The hose then takes a while to get quite hot and then the thermostat appears to open and the other hose gets hot.   Would the incorrect temp reading cause a problem (i.e. faulty ECU responce)
VCDS now seems to be showing two fault codes - the one for the ignition and another one for the Airbag. (see photo) 

Cheers

[KenONeill]

@mexmeister - OK, the VCDS and observations seem to indicate that the thermostat is OK, so the most likely issue is the coolant Temperature Sensor.

 

Ref the airbag, is the warning light coming on and staying on rather than illuminating as a BITE? If not, then that is non-urgent.

[RicardoM]

12 hours ago, mexmeister said:

So you think it would be worth adjusting the timing manually to see if this helps?   I have go a timing light somewhere.

The distributor has a Hall sender, not old-style contacts. The setting of ignition advance is done using a special device.

14 hours ago, mexmeister said:

When driving at normal speed, in the summer the needle only gets to about 70 and in the winter it pretty much stays on the bottom stop (60).  It only goes up significantly in slow moving traffic.

I know you have changed the coolant temp sensor but check its output according to diagram below. Check also that the thermostat stays closed up to 82C by feeling the thick hose that goes to radiator. If it stays cold up to 82C then warms up, you're good. It is very probable that if you changed only the thermostat without  its housing, there is a gap that allows coolant to flow all the time in the long cooling circuit. If both CTS and thermostat are OK, the temp gauge is faulty.

[RicardoM]

For an engine idling, the ignition coil error reported by the ECU is very strange because the engine shouldn't run or run like a tractor. I mean, if the error is permanent.

What puzzles me is the air intake temp indication of 79C...

[mexmeister]

Thanks for your help with this gents.  It looks like tinkering with the timing is not something that I'm easily going to be able to do.   As it happens I've already ordered a new temp sensor, which should arrive in the next couple of days.  Hopefully the temp indicated by VCDS with be normal once fitted.  My feeling is that the thermostat is probably working OK, as the hose that goes to radiator gets pretty hot before the thermostat appears to open and allow flow.  Ricardo - I'm also a bit puzzled by the ignition issue, as although when driving the pickup it doesn't 'feel' quite right and I have the pinking ussue, in general the engine seems to run ok.  From cold the engine turns over and starts 1st time pretty much immediately with no extended turning over.  Idling is strong and constant - no significant hunting and I don't have any issues with rough running.  It pulls quite well with no apparent ignition break down under load.   It can be a little tempremental starting when it's still warm, but it always starts after a bit more turning over.  My main concern is getting through the MOT in a few weeks time.  I'll fit the new coil pack and temp sensor and see if that improves the situation.  I'm being advised by a few people to get shot of the truck and buy something 'younger and more reliable', but despite all it's issues, I'm pretty fond of it and want to try keep it on the road.

Ken - the airbag warning light on the dash has never illuminated.  The bulb still work as the light comes on when key is turned to the aux position.  I thin it's just ignore the issue and maybe it will go away - but then again!!
Cheers

[RicardoM]

5 hours ago, mexmeister said:

My feeling is that the thermostat is probably working OK, as the hose that goes to radiator gets pretty hot before the thermostat appears to open and allow flow. 

That is exactly what I was telling you it's not OK. The hose that goes to radiator should stay cold during engine warmup. The thermostat opens to allow coolant flow through radiator!

5 hours ago, mexmeister said:

Ken - the airbag warning light on the dash has never illuminated.  The bulb still work as the light comes on when key is turned to the aux position.  I thin it's just ignore the issue and maybe it will go away - but then again!!

Any airbag error disables it. In case of accident it will not deploy.

[mexmeister]

Hi Ricardo - during warm up the top hose only slowly gets hot and I think it may simply be 'bleeding' through the thermostat.  The radiator remains cold as does the bottom hose, so I'm pretty sure there's no water flowing through the radiator.  It's only when the top hose gets quite hot that the thermostat appears to open and there's then flow around the rad and bottom hose which then get hot quite quickly.   I just drove the pickup about 6 miles and immediately after stopping I checked and the top hose was getting quite hot.  However, the rad and bottom hose were still pretty much cold.   Ref the airbag issue - whilst a non functioning airbag is not ideal, there's no warning light showing on the dash, so at the moment sorting that out isn't my top priority. 

 

Cheers

[RicardoM]

5 hours ago, mexmeister said:

during warm up the top hose only slowly gets hot and I think it may simply be 'bleeding' through the thermostat

Bleeding is not acceptable. It's your call. You can disregard it as you decided to do with the airbag. My opinion is that since you asked and you got all the help from us, you should do all tests to pinpoint the culprit for the temp gauge, running rich, and airbag in this order.

[RicardoM]

2 hours ago, RicardoM said:

...you should do all tests to pinpoint the culprit for the temp gauge, running rich, and airbag in this order

The first two might be related.

[RichardatWakefield]

Er, is it possible when the recentish work was done on the cooling system, that somehow the wiring to the coolant temp sensor and air intake temp sensor got cross-connected, leading to those weird readings of coolant 17.6c, and intake air 79c??? 

 

Richard.

[RicardoM]

Richard, very interesting observation. Might be a coincidence but the air temperature sensor goes to pin 43 of ECU, while coolant temperature sensor goes to pin 42 of ECU... which makes you wonder...

[mexmeister]

Interesting indeed.   However, I fitted the new thermostat housing myself and I know I've have never touched the air temp sensor.  I guess it's possible something happened before I purchased the car - or could it have happened during the head gasket repair?  However, what's also is interesting is there's a forum post from 2011 where there's someone with similar flipped readings for air and coolant temperatures showing in VCDS-Lite.  There's a comment about VCDS-light not always having the correct measuring block labels.   All being well I'll be fitting a new coolant temp sender and coil pack tomorrow.  If I've got time I'll also investigate the airbag wiring etc.
Thanks for your help. 
 

 

[mexmeister]

I changed the Coil pack, complete thermostat and housing (inc coolant sensor) today and the ignition fault no longer appear in VCDS.  What was interesting was that following the comments about the low coolant temp and high air temp readings in VCDS, I examined things a bit more closely and it appears to be a glitch in VCDS.  (see attached pics)  as can be seen, when viewing groups 1, 2 and 3 together, as was noted before, the coolant temp in very low and the air temp very high (appear transposed).  However, if each group is viewed individually, the readings are suddenly correct.   The cooling system seems to be working OK.  Using VCDS I monitored the temp value whilst feeling the cooling hoses/rad.  The thermostat opened at about 86 degrees and the fan then kicked in at 96 degrees.  However, when the engine was warming up, the the top hose near the thermostat still got quite warm before the thermostat opened.   Hopefully the new Coil pack will sort out the high emission problem.  I'll get it tested at the end of the week.   I also cleared the airbag fault and it hasn't reappeared. 
One thing I did find was that there there appears to be a dodgy hose at the rear L/H top of the engine.  The hose appears to be cracking up and the previous owner has wrapped some insulation tape round it.  However, the hose is collapsing in on itself and is therefore almost blocked .  I've arrowed the hose in question in the attached photo.  Can anyone identify what hose it is, (ideally with a part number), as I would like to replace it - although it looks like it may be fun getting to the bottom fixing. 
Thanks

[RicardoM]

1 hour ago, mexmeister said:

Can anyone identify what hose it is, (ideally with a part number), as I would like to replace it - although it looks like it may be fun getting to the bottom fixing.

That is a hose for the crankcase ventilation. Part number 032103493K.

 

About emissions part: hopefully you cleaned very well the spark plugs. Do a trip on a highway with 60-80 mph, return, leave the engine to cool off then look at spark plugs again. Monitor the temp. gauge too.

[mexmeister]

Hi Ricardo - thanks for the info on the hose - much appreciated.  I've done a quick search on the web and it doesn't look like I can get one in the UK, but I'm hoping I  can source one from abroad.  Could the existing almost blocked hose have an impact on emissions?  

Cheers