10 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHInterpreting OBD2 readings
Leading reported evidence
Run right
Suggestion or failed attempt
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
I recently got an OBD reader off the back of another forum members recommendation as I felt the car wasnt quite running right.
Leading evidence: 'Run right' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Run right' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
So the main complaint is below par performance as per surrey rolling road test for a 3.9.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
10 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
911uk: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T194705Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi all,
I recently got an OBD reader off the back of another forum members recommendation as I felt the car wasnt quite running right.
The bits that look a bit off are the fuel trims between the different banks and also the oxygen sensor readings maybe.
Any help on interpreting these readings would be much appreciated!
I dont have any fault codes but from a bit of background reading it looks like a fault code wont be triggered until the fuel trim exceeds 10%
The symptoms are slightly rough idle and excessive fuel consumption.
Further reading suggests it could be a vacuum leak?
Could be a numerous amount of things, not just vacuum leak. If it hasn't tripped a CEL then everything is within limits so should be ok.
What's excessive fuel consumption? 5? 10? 20?
What would you describe as your main complaints?
High fuel consumption?
How is the idle? How does it sound? How is the power delivery?
Negative fuel trim indicates the ECU is reducing fuel, as it is detecting rich combustion. Seems odd with a motor that has been enlarged.
How new are the O2 sensors? Were they replaced as part of the rebuild? Were the injectors cleaned and tested?
So the main complaint is below par performance as per surrey rolling road test for a 3.9.
The idle does fluctuate slightly and the power delivery can sometimes be a tiny bit jolty.
I also notice that one bank smokes more than the other on startup.
I dont have any records of the injectors or o2 sensors being replaced
If it's a 3.9 oversize Hartech engine it's only been done in the last couple of years - call them. Where's the rolling road place getting their comparison from, another Hartech 3.9 engine or a 997 3.9?
