Intermittent stop - start jerking

[drover]

"They put a sealant there" ....?????????

Getting closer to the problem I think, you have to remember diagnosis of an oil burner is not same as petrol....

Next question does the miss appear when stationery and bringing it into the rev range ??

[OLMATE]

Silicone Sealants can poison O2 sensors, need to use Sensor Safe such as this https://www.permatex.com/products/ga.../?locale=en_us

[afnan]

Originally Posted by drover

"They put a sealant there" ....?????????

Getting closer to the problem I think, you have to remember diagnosis of an oil burner is not same as petrol....

Next question does the miss appear when stationery and bringing it into the rev range ??

I don't trust any mechanic after having this experience by the dealer themselves. Switching back to being a DIY guy. The people think I am saving money - whereas, I am buying peace of mind.

Yes, it happens on low rpm cruise lets say 100-1400. I am at point of giving up on the issue and wait for a bigger fail to happen. This is interfering my day to day thinking now

[afnan]

Originally Posted by OLMATE

On the Ol Mechanical diesels, when out in the field one way to find and isolate air leaks was to spray aero start around the suspected air leak, worked a treat everytime as the engine would rev indicating its inhaling the fumes from the aero start ( ETHER ) bloody volatile shit

Now isn't this interesting. I have been running GC with EGR Valve connector unplugged and it runs fine. I wonder what will happen if l let it unplugged. The car seems to be happy with no flat spots or jerks. If it was due to any other thing than EGR valve then it should be there.

ill keep running for a week and will report back.

Couple of other questions that I have.

1. Would you know what should be the default Lambda sensor voltage levels? in gasoline, it should be close to 1 for perfect air to fuel mixture.
2. Since EGR brings gunk in the system, why they did not get exhaust gasses after PDF and feed clean gasses back?

[drover]

If it works disconnected and no lights coming up then I would leave it go, the EGR only operates for a small amount of time anyway................
The Lamba or oxygen sensor on these things I assumed were mainly for DPF stuff but I will try and dig into the manual sometime today if I get a chance and see what its test regime is, haven't had to play with one since my ZG and it was petrol and a long bluddy time ago.
It is an interesting problem though, thankfully its yours as it would drive me nuts...

[Treebreakerbob]

Originally Posted by afnan

other question that I have
2. Since EGR brings gunk in the system, why they did not get exhaust gasses after dPF and feed cleaner gasses back?

Probably because on DPF burn off heat would be a problem, and it would be a long way back to the engine from the end of exhaust system, but I like your lateral thinking. The other reason is cost and another is they are dickheads and no one thought of it.

[drover]

Had a look in the bible about Oxy sensor in the diesel, what a pain to look for have to dig thru all the petrols, anyway looks like one sensor, no sign of any testing details, did note " when fuel rail/injectors adjusted/moved that they said using the scan tool the Oxygen Sensor Value Reset should be carried out " also found there's a Noox sensor near it as well, there also appears to be MAF sensor reset in the Scan tool under the Engine Misc. Functions most interesting...................

The EGR sucks in soot so it gets to be burnt again before the Soot Oven makes sweet exhaust fumes, thankful we don't have the Adblue crap as well.......... rubbish idea.