2000 S70 AWD, no start issue. Topic is solved

[amolnar0829]

I feel like I have searched and searched the internet to find a solution, but if I have missed something of coarse feel free to clean up and delete this mods...

Here's the situation:

Backstory:
I made changes to the induction system and boost control system. I converted the MAF to blow through to avoid stalling issues from how I modified the BPV.

It was struggling to start up as it got colder out... then would not start.

Replaced Coolant Temp Sensor, since that was reading wrong. Starting up.

Not starting up now. Blowing black smoke out exhaust while cranking.

Engine has good compression.

Fuel rail has good pressure.

It started on starting fluid for a few minutes.

Played with the Fuel Relay, not able to start it still, when having friend plug it in and out really fast to try to reduce fuel flow (black smoke seems to indicate its way rich).

On a hunch that fuel regulator on pump may have failed, replaced pump. Car still wont start.

SNAPON scanner says upstream O2 not found, downstream has low reading (downstream is not in the exhaust, my car is not catted.

The

Car starts in open loop, not closed, so O2 should not matter for fuel/air mix?

ETM was recently replaced with a compatible year turbo ETM. It was working fine with none of the symptoms of failing ETM.

Mass Airflow went bad, probably due to blow through MAF set up. I had made my own tubing to convert to blow through. MAF replaced with new or known working.

Parts I bought and have not installed yet: NEW Spark Plugs (NGK 6619 Iridium LFR6AIX-11) & used Volvo turbo air intake pipe to return MAF set up to stock.

Car needs right mix/timing of Fuel, Spark, Air to start up.

Fuel: Pump is new installed and I have recently had the injector rail on and off a few times before this starting issue and inspected the injectors. They looked clean. I was also disappointed that replacing the pump didn't fix my fuel gauge from reading zero.

Spark: I have 1 month old plugs in the car but they look pretty fouled (blackish carbon coating all over the sparking area. I have brand new NGK plugs sitting by I intend to install tonight...

Air: I have a used replacement air intake piping from intercooler to throttle body I intend to also install tonight... it comes with MAP and BPS in it also... Motor had good compression.

At this point... I am totally stumped. The person I am working on this with, owns his own shop and works alone. Volvos are the most common cars he works on with at least 2 in the shop as projects for himself or customers at any given time. Last month he had 5 in there. This guy has built up alot of credibility with me but I want to have as many ideas as possible so reaching out to the enthusiast online community here with some hope...

Any advice? Could some other sensor or fuse be the culprit? Is it possible something else may be creating the black smoke symptom that we are seeing during attempts to start the car?

[abscate]

Definitely get it back to stock MAF and setup.itshard to troubleshoot such a major mod with no history

[amolnar0829]

Thanks for your response!

Went back to stock MAF set up and put the new plugs in at the same time also. It started right up. It's been incredible in the heavy snow fall we had last night, what good timing.

I am now struggling with a poor idle and the the rpms will dip and jump so much when off throttle it will often completely die and need to be restarted. I am now hunting a resolution for this. I believe it may be a vacuum leak and BPV block off plate compound issue confusing the cars air/fuel mix and leading to this. The solution according to my pro mechanic friend is to potentially replace the pre-turbo intake tube and to return BPV to stock. Unfortunately I have a love to improve performance past original design to create something more fun and interesting... Cheap, Reliable, Fast, pick two... I don't have alot of money

[scot850]

What is the history of your ETM? Has it been upgraded/repaired before install, or is it an original. If it is it sounds like some of the symptoms of a failing ETM.

Neil.