Part 4 - 1998 Bentley Brooklands R Fueling Puzzle. Crowd sourcing a solution.

[@glassheadlamps5723]

Thank you for the regard. It was a pleasant surprise. It's probably me not watching the videos fully but I didn't know that you had trouble codes stored. Those are interesting. But before then: your live data reads intercooler air temperature. -40 degrees. Gibberish? Maybe not. Looking at some of these models. Some came with intercoolers but yours doesn't have it? Did you verify that the ECM in your car is the correct one? I read recently that someone with a W126 had a 4.2l ecu in the 5.6l car. It was running fine except for some niggling issues. He could never get to the bottom of it until that discovery was made. You'd never think of something like that. I hesitate at saying anything as 'aha' with these cars and their low volume productions adding to their peculiarities. But if this car were to have no intercooler, I'd expect live data to read "N/A" rather than a value (any value no matter how implausible it was). It should know that there is no intercooler temp to be read as the ECM output has no measure for it. The low production numbers also make spares tough to come by. If it's being worked on and the ECM is fried and one is available but not for that specific model do they wait, or get the one that gets the car working to 90% and send it down the road? Depends on the shop. The codes O2 sensor for Bank 1? That means Bank 2 is ok? So three sensors in total or does it just read one bank and this is pre three sensor days? Is this the one you replaced in an older video? You're getting correct functioning values for a working sensor (open/closed loop) but it seems to be not working with the car. Air injection pump. Is this the air pump incorrectly/not pumping air into the exhaust? That would throw off the O2 readings wouldn't it? Yes air not pumping in would lean it out as it's reading rich but cold start can have an default of preset rich mixture negating this. I could go into more about this but I kind of make myself no better than any other armchair online expert as I simply have no idea what's going on here. I would sincerely enlist the forum experts on this or (what I would myself do) get schematics of the car's wiring. Figure out what wires go where for the ECM. And subsequently what does what for the resulting function. I have in awe watched South Main Auto (and a few others) at diagnosing things and see how important it is to have a firm base level to reference resulting measures from. There have been a couple of times where a car has 10 codes and he tries to find the most common denominator (that would otherwise be shrouded were it not for diagnostic/schematic data) and that clears out half to most of the codes. Not saying this isn't this but those trouble codes would be the thing I have a direct goal of correcting. There's a better chance that that will fix the rough running rather than trying to fix the rough running to resultingly get rid of the code(s). Please keep us informed. I'm getting more curious as this is developing.

[@aalabbasi]

Thank you for your input, sometimes, just kicking ideas around helps drive new tests. I still have a couple of more things to try. As far as the intercooler is concerned, I did check part # on the ECU and it seems that it was used across models. This one is a light pressure turbo, so it has no intercooler. I’ve owned the car for 6 years, and this is a new problem so I don’t want to assume that it was the wrong ECU, although the ECU may have new problems. There are only two oxygen sensors, bank one sensor one and bank two, sensor two. I assume this is because it’s a single large turbo, so you have a single large pipe. My experience with secondary air injection is that it does not affect the running of the car but will trip codes of the computer read that there are unburnt gases in the going to the cat. No amount of air from that pump will bring the rich condition back to normal but I agree with you, the manual is the way to go, and I do have it along with wiring schematics. It’s on a CD rom which is very clunky. You must set the clock back to 2013 and the information is very fragmented which makes it difficult to digest. It could, for all I know, still be the residue of the bad gas that’s in the tank which is causing the system to lose its mind. I’ve switched gears to the Turbo R right now in hope to get some of the body work done before summer hits. I have about a month before the building gets very hot.

[@Mercmad]

I was wondering if you've done a exhaust pressure test? It's starting to sound like blocked cats. Also, does that injection use a cold start injector? the blue plug hanging loose looks like a cold start injector connector. If it has a cold start injector ,have you checked it to make sure it isn't leaking when hot?

[@aalabbasi]

Ron, it does sound like it's missing but it's moving a lot of air so I assumed the cats are not restricted. If it keeps running this way, they will be.

[@cav4290]

Did you check the TPS? I suggest to swap out the MAP from your other car.

[@aalabbasi]

The scan tool is reporting info from the TPS, you can see it in the live data