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Hello mini nerds, I am reposting this to what I hope is the correct place
I have a stock tune Mini Clubman N18 Manual. Upgraded intercooler, piping, and cold air intake, as well as a single mass flywheel (
The car throws no codes, idles smooth and generally makes up to 15-18lbs, though lately it's been rare to get it to 18. The car 2 years ago felt much faster than it does now and I'm lost.
I have a brand new boost sensor, map sensor, diverter. PCV systems appears to be functioning properly though I don't know for certain. Oh the intake valves are also pretty clean.
I believe that leaves me with the boost solenoid and waste gate to check but frankly I can't keep throwing parts at it, I want to diagnose this issue without doing so.
I feel a very subtle oscillation in power when going up hills. Boost feels laggy and doesn't feel like it's holding through gears, power seems to fluctuate day to day. My miles per gallon appears to be suffering slighty, though the car passed emissions fine.
i have Bimmergeeks Protools adapter, and I am getting a boost reading of -1.85 to -2.21 at idle and that seems off the mark to me though everybody I ask doesn't know if it's normal or not.
Please somebody please help me. Does this sound like a wastegate issue or boost solenoid? What are your stock idle boost readings?
it should be around -2 vacuum
at idle and low load it should not produce boost
edit- I replaced my diverter valve and it spooled up better. The old one if original may be bleeding boost pressure.
I certainly want to get a tune but my car has these fluctuations and slight power oscillation when I'm going up a hill. I want to make sure everything is solid before I do so. My mods and no tune shouldn't be causing my issues right?
The car was faster 2 years ago with stock everything. It didn't get slower when I put them on, it got that way and then I installed them.
-2.2 seems low based on what others have said. I've heard it should be right under 0.
Like I said before , to me it feels like my car has to overcome this -2psi and in turn makes it feel laggy.
My 2012 R58 Coupe has the N18 as well. Like I stated, having a vacuum at idle is correct. Stock the highest boost I have ever seen is 16. I have added a JB+ and with it the low end stayed the same, the high end has hit 20, 18-19 is real common if getting on it hard.
My 2012 R58 Coupe has the N18 as well. Like I stated, having a vacuum at idle is correct. Stock the highest boost I have ever seen is 16. I have added a JB+ and with it the low end stayed the same, the high end has hit 20, 18-19 is real common if getting on it hard.
I agree with DFSGM - having vacuum at idle shows no leaks at idle. There might be a leak under load - which can happen. Hence would like to see boost plotted over rpm ( ie how well does it hold boost ).
If your system is sluggish, it might be do to non turbo things on top of things you looked at: Electrical - Spark Plugs, Plug wires; Airflow: Clogged cat, Clogged Airfilter ... Fuel: Fuel filter etc.
I would not worry about going to a "custom" tune - not canned, as it would give diagnostics of the A/F ratio as well as few other things that could help diagnosis what is going on. There are people on this list that do this. Tigger on this list ( lou@prototype-r.com ) is one. But this should be able to be sorted out without this. I am a big fan of collecting all the data you can.
How many miles again ?
Do you have stock cat and stock exhaust ?
Your intercooler most likely added 0.5 psi pressure drop, but that should not be bad ( and most people just turn the boost up 0.5 psi on a tune to accommodate, as well as play with timing and A/F ratio to take advantage of that extra cooling ... ).
I know this is frustrating and these gremlins are like whack a mole: fix one and another pops up ! Stick with it !
I agree with DFSGM - having vacuum at idle shows no leaks at idle. There might be a leak under load - which can happen. Hence would like to see boost plotted over rpm ( ie how well does it hold boost ).
If your system is sluggish, it might be do to non turbo things on top of things you looked at: Electrical - Spark Plugs, Plug wires; Airflow: Clogged cat, Clogged Airfilter ... Fuel: Fuel filter etc.
I would not worry about going to a "custom" tune - not canned, as it would give diagnostics of the A/F ratio as well as few other things that could help diagnosis what is going on. There are people on this list that do this. Tigger on this list ( lou@prototype-r.com ) is one. But this should be able to be sorted out without this. I am a big fan of collecting all the data you can.
How many miles again ?
Do you have stock cat and stock exhaust ?
Your intercooler most likely added 0.5 psi pressure drop, but that should not be bad ( and most people just turn the boost up 0.5 psi on a tune to accommodate, as well as play with timing and A/F ratio to take advantage of that extra cooling ... ).
I know this is frustrating and these gremlins are like whack a mole: fix one and another pops up ! Stick with it !
I hadn’t thought about boost and throttle lag from the bigger intercooler… depending on brand, eBay for example, some cheap aftermarket intercooler aren’t great. But, if you say it started having perceived issues prior to installing the intercooler, then…
I agree with DFSGM - having vacuum at idle shows no leaks at idle. There might be a leak under load - which can happen. Hence would like to see boost plotted over rpm ( ie how well does it hold boost ).
If your system is sluggish, it might be do to non turbo things on top of things you looked at: Electrical - Spark Plugs, Plug wires; Airflow: Clogged cat, Clogged Airfilter ... Fuel: Fuel filter etc.
I would not worry about going to a "custom" tune - not canned, as it would give diagnostics of the A/F ratio as well as few other things that could help diagnosis what is going on. There are people on this list that do this. Tigger on this list ( lou@prototype-r.com ) is one. But this should be able to be sorted out without this. I am a big fan of collecting all the data you can.
How many miles again ?
Do you have stock cat and stock exhaust ?
Your intercooler most likely added 0.5 psi pressure drop, but that should not be bad ( and most people just turn the boost up 0.5 psi on a tune to accommodate, as well as play with timing and A/F ratio to take advantage of that extra cooling ... ).
I know this is frustrating and these gremlins are like whack a mole: fix one and another pops up ! Stick with it !
118k miles, stock cat/dp, stock exhaust. Swapping the intercooler back to stock didn't make any change, though initially I thought it did, it was just the intermittent factor I was fighting.
I've changed plugs and coils as needed, though I am running factory plugs, Ive been meaning to switch to ngk.
I have the ability to catalog with Protools but I'm not sure where to plug that data into to give me a graph.
How bad is the 'seat of the pants' drop in performance ? Is it during immediate acceleration or just at higher loads ? Is it intermittent as you said or all the time. Again, this might be an engine that is in the elder years ( rings etc ... ). Or it might be not holding boost, or ..... ????
I am not sure this is much more than guess work at this point until we can rule some things out. I am not a data logger - just have looked at them. Perhaps someone can chime in to see if you can a boost, a/f ratio vs rpm run plotted if you have the means to download. Not sure if it is just a text file, comma separated file that you can plug into Excel or etc ...
I would look at the plugs for the heck of it and consider replacing ...
