I have a 2012 Seat Alhambra 2.0 tdi Ecomotive 177ps. It smokes really badly at hot idle, think it’s a fuelling issue.
My original motor failed, and I purchased a good replacement motor from a breaker Motor came from a crashed car and has only 60k km. It came with original DPF, turbo, injectors and HP Pump. Mileage is verified. My mechanic is good, but I think he finds modern diesels difficult. Now I have car back it drives really well, no smoke when cold, smooth running, quiet, good acceleration, no misfire. The problem is smoke when idling. The smoke is very bad and fumes make my eyes hurt. When I drive hard there is no smoke, only in town waiting for lights. It seems like the problem is over-fuelling at idle. Also I will have to fix this myself.
Symptoms are like car in permanent regen, a stuck injector or possibly adaption of new injectors was done badly by mechanic. There are no warning lights up and no DPF light. I have VCD’s and I am a good mechanic, just don’t have much Tdi experience but can take direction. Injection Deviation is as follows.
Deviation Cyl 1: 0.74 mg/stroke
Cyl 2: -0.16 mg/stroke
Cyl 3: -0.88 mg/stroke
Cyl 4: 0.33 mg/stroke
When I put CSV data in a graph cyl 3 looks lower than the others. (I can’t work out how to post images)
Is there anything on VCDS I should be looking at to help diagnose the issue?
Also my mechanic had trouble with jammed Adblue nozzle from crystals. If he made hole too big could high adblue injection cause this problem?
Any failure entries?
Is the air filter fresh?
How is the oil consumption?
use drag&drop (on PC)
Too much AddBlue would smell like ammonia. You should not tamper with the nozzle. Urea crystals are water-soluble (use warm water). Mechanical treatment should be avoided.
Are you able to see the lambda values in VCDS to tell if the mixture is too rich?
Thanks,
Not Ammonia Smell. I Will look at lambda values tomorrow, what values should I be looking for?
Also I will take vehicle on run at regen speed up the motorway. Filter and oil are fresh, had a full service plus clutch and dual mass flywheel when engine got changed.
I had seen that. I actually think my original engine blow up was linked to @boldor 's issue. I had similar issue a lot of regen’s etc… the dilution of the oil caused turbo seal failure which put more contamination into the oil which destroyed engine turbo & HP pump. When my mechanic changed the motor, he heard rattle from catalyst, it was broken up, like Boldor’s. The catalyst in my car now is empty, I work as an engineer. I cut catalyst box open, took all pieces out and welded it closed. So my situation is not the same, the catalyst is not blocked but the conditions that caused the damage may still be there. You change a motor but all the other sensors are still there. I need to find out what are „normal“ readings so I can diagnose the issue.
Update: 2 fault codes showing. 9622 Control Circuit for Reductant Heating 1 (open circuit)
9622 Control Circuit for Reductant Heating 2 (open circuit)
Came back after faults cleared so not an old one. Similar faults on Tdi forum says it may just be bad earth. I’ll try but I don’t think this is fix to my smoke problem (too easy lol!). Car just back from cold garage so earth issue no surprise.
Also, I went on long drive. I can drive 100,000kms with no smoke as long as I am over 1,000rpm. Smoke only comes with motor at full temp (90c) and at idle.
Ok, No fault codes showing (bad connection for reductant heater) went on a long run no regen status showing on VCDS. Excellent running and acceleration, no smoke in normal driving. V-bad smoke and noxious fumes at idle.
These are readings. Coolant temperature is strange. Instrument reading says 90 deg C, VCDS says 75-76c.
Thanks for that, explains it. I put a new temperature sensor in as it was very cheap. Highest temperature I got after a long drive and sitting at idle was 80 degrees c coolant temp, with VCDS. I think no catalyst probably helps, before blow up I was getting fan running for a long time after stopping. Not anymore.
Smoke is white and burns my eyes. Not water though, I’ve been on long drive and checked level.
Maybe water is „burnt“ only at ildle? (Only guessing, I would not know why or how this could happen.)
Is there a way (using a condenser) to capture all the water which is coming out of the exhaust pipe and if that is the correct ammount based on chemical formula and all coming from burnt fuel?
E.g.: 0.5 liter Diesel fuel (which is usually consumed during 1 hour of idling) will deliver 0.5 liter water in the exhaust gas.
Also, I would disconnect the urea unjection system, so that there is for sure no injection of AdBlue taking place.
I found this source (Diesel is very similar to heating oil):
Bei der Verbrennung von 1 kg Heizöl EL entstehen 1,18 kg Wasser. Bei einer Heizöl-Dichte von 0,85 kg/l (15°C) folgt daraus, das bei der Verbrennung von 1 l Heizöl etwa 1 kg (1 l) Wasser entsteht. https://www.haustechnikdialog.de/Forum/t/18018/Oel-Brennwerttechnik-Kondensation
I have found a good DPF and SCR Catalyst, I think some of the problem is leaking from the welded catalyst causing problems with the fuelling. I need some information on removing the DPF, do you remove it from the top or the bottom. If from the bottom does the front subframe have to be completely removed or can it be dropped slightly.
