Freelander 1 1.8K lumpy start from cold.

[PRO]

Hi, me again.
I've noticed lately that when I start the car from cold, there is a heavy smell of petrol around and it runs lumpy for about 30 seconds give or take. Feels like a misfire but I can't see any logged in OBD.
Spark plugs are new (ngk iridium) and two coils are also new and genuine lr.
No visible smoke and runs very well afterwards.
I have very good diag any idea if I start it on what values I should look?

 

[PRO]

Actually I do have some values and errors. Says cat failure however the cat is brand new, therefore before I look into changing this quite expensive part, can a sensor cause this?

 

[kermit_rr]

Were faults cleared after the cat was replaced? The post cat o2 sensor will help decide whether the cat is working or not

 

[PRO]

They were, I check and clean faults every week and this was not there last week.
Car is also lumpy so something is happening not just the sensor, I suspect.

 

[kermit_rr]

Do you have the fuel trim values?
Is the coolant sensor reading the values you'd expect? Ie accurate value when cold?

 

[PRO]

yes it is, will check for fuel trim. Since the petrol smell, I am guessing there is fuel going in the cat.
At this point I will be looking on the o2 sensor, map sensor, exhaust leaks or anything that causes the ecu to overfuel on cold.
Would gladly accept any advise as well.

 

[kermit_rr]

Air intake leaks will cause it to over fuel too

 

[PRO]

Well yes but why it clears up after a minute puzzles me. Should be more constant to be honest...

 

[andyfreelandy]

Check temp sensor not telling porkies?

 

[PRO]

Hi Andy engine cooland or air? Does make some sense.

 

[PRO]

At this point I've replaced the remaining two coils. Symptoms are the same, nowhere near to fix.
Temp sensors are working fine.
I am starting to blame the o2 sensor, the pre-cat one. Any idea what values to test and how?
Car is not losing oil or coolant, runs fine after a min. Shaking on cold start.

 

[PRO]

Alright, replaced the Upstream o2 sensor with genuine bosch one. Things did improve as there is no more petrol smell on start.
However, still violently shakes for a minute or two.
Now, from time to time I can also feel it kicking on idle.

Replaced all these with genuine MG/LR parts, new:

Upstream O2 Sensor
All spark plugs
All Coils
52MM Throttle with new TPS
IACV valve
Air filter
Rocker cover

I am out of ideas at this point. Does the downstream o2 could for running or simply checks the efficiency of the cat?

 

[Nodge68]

Upstream O2 Sensor
All spark plugs
All Coils
52MM Throttle with new TPS
IACV valve
Air filter
Rocker cover

That's covered pretty much everything, except the fuel delivery system. Have you checked fuel pump pressure and supply volume?

Does the downstream o2 could for running or simply checks the efficiency of the cat?

Cat efficiency only.

 

[PRO]

Indeed, did not touch the fuel system yet. I do have a new fuel filter.
Can I check any of these with delphi? I am tempted to replace the whole pump and filter (one on tank if it's the only one) since I am removing it anyway.
Somebody else told me it might be even the injectors... although these are quite expensive to replace. And labour intensive if I have to remove the inlet manifold for that...
Which does bring the question if replacing injectors require removal of manifold or can be done without? Got a extremely sweet auction deal on vdo pump will be changed regardless.

 

[Nodge68]

Indeed, did not touch the fuel system yet. I do have a new fuel filter.

It's quite common for the filter to clog up.

Can I check any of these with delphi?

No. You need to use a mechanical gauge on the fuel rail test point.

I am tempted to replace the whole pump and filter (one on tank if it's the only one) since I am removing it anyway.

Yes the pump is in the tank.

Got a extremely sweet auction deal on vdo pump will be changed regardless.

Make sure you get the correct part number, or the fuel gauge will work backwards.

 

[PRO]

microcat says WFX000210 and vdo alternative is 228-232-003-003Z (after vin 2a I think) mine is 5a.

 

[PRO]

Changed pump, not much improvement. However now for some reasons shows full tank start from time to time.
Bit of a problem, I don't know how much fuel I have. It is intermittent.

 

[andyfreelandy]

Faulty fuel level sender which is part of pump assembly.

Return it for replacement. Or if you think your old one was OK just return it for refund!

 

[PRO]

Maybe I did something wrong, pump came new vdo branded, unopened unused. Will check shortly

 

[td4van]

Did you get the right pump/sender for the age of your car? As fuel gauge can work in reverse with the incorrect one.

Or the float arm maybe getting snagged in the tank