Hope is isn't something too serious, let us know what you find out.
43,0000 miles. Yes it was P0234. I believe all recalls were done. Original owner. Yes turbo replaced already after EGR was fixed. All under warranty. I will find out tomorrow what exactly it is. I will post when I find out.Couple questions to answer to see if we can figure out anything more here:
Vehicle: 2018 Lariat 3.0L V6 PSD
No guarantees on diagnosis but we can flesh things out further here.
- Current mileage?
- Actual ODB code/number thrown? P0234?
- Status of 18E02 EGR By-Pass valve recall?
- Status of 20E04 EGR By-Pass valve recall?
- Are you indicating that your turbo has previously been replaced also?
- If so, can you provide some background/history behind this previous failure?
- Was the turbo replaced under warranty?
- Original owner? Or did you buy used?
2018 Model year = your truck was subject to both 18E02 and 20E04 By-Pass valve recalls
=> Hence why I am asking for the recall status for both recalls=> If you are unsure, ask your dealer for a VIN-specific OASIS report=> OASIS report will contain any-and-all recall work Ford has done on your truck
I think the only other P0234 we have seen here was Post #56 from @flharrison in the infamous START HERE: Any owners affected by FSA 18E02 (EGR By-pass valve replacement) thread, which was clouded by being at the same time as the 18E02 recalls. If you follow his updates in that thread, I think they found a loose pin in the VGT in the turbo and some form of exhaust leak.
Welcome to the forums = wish your intro could have been on a better note...
Thanks I am going to a different Ford dealer to see if they can fix the issue. Starting to piss me off this shouldn't happen.Strictly speaking this can only be from the turbo vanes being stuck on the full boost mode as I don't think our trucks have a waste gate. I am also guessing it could be faulty wiring, a bad sensor or even a defective PCM. A good Ford technician should be able to figure it out. This is from the Coffee Table book and explains the turbo operation.
View attachment 2548
Here is a screen shot that might also demonstrate it can be more than one sensor. I can't find a turbo overboost sensor, I am not sure if there is a specific sensor or if the PCM measures multiple sensors to determine an overboost condition. This screen shot mentions the ECT, MAF and MAP but not an overboost sensor. I just don't know.
View attachment 2549
Note on this that the overboost is detected by high exhaust pressure.
Like I indicated earlier, @fharrison got his P0234 right in the middle of the original 18E02 EGR Bypass Valve recall = I probably should have split his P0234 issues off into a new thread at the time. Mea culpa!An update....dealer replaced the EGR but then found a vacuum leak. Have a feeling that was actually responsible for EGR efficiency and overboost problem since both of those are vacuum actuated. May have not been a problem with EGR at all. Will find out tomorrow.
IF (desired boost pressure - actual boot pressure) < ~15.0 kPA for > 7 seconds, THEN throw P0234 DTC
Very useful information. Thank you.Kind of sounds like you've already made up your mind. Just a couple points for consideration: A 6.7L will consume 30% more fuel; something to consider with the world's #2 oil producer invading a European country this week. It is also not immune to its own share of issues, including a TSB for snow in the air filter (from one of your other posts). Price out a DPF on a 6.7L versus a 3.0L, which is an item not included even on extended warranties since it is considered a wear item. I would argue that if you are looking for a drive it and forget it truck, you should be looking to a 5.0L F-150 or a Tundra.
If the MAP sensor is on backorder, there is at least one on eBay. I had one fail on one of my other vehicles; swapped it out in 10 minutes for $27. I was under warranty, but the hassle was not worth $27 to me.
As a final point, there is a note by @jmperlik a few posts up regarding the lack of a wastegate as a possible reason for the lack of an engine brake on this engine. I have 5 turbo vehicles including a 6.6L Duramax. None of them has a wastegate. In fact, the last wastegated turbo that I owned was a 1987 Audi Quattro. I think variable vane turbos have made wastegates redundant; in fact, it is the VVT that actually serves as the engine brake in vehicles coded to use them as such.