Engine Cutting out in boost
#1
Engine Cutting out in boost
Hi everyone! I'm new to the forums and new to tuning.
When I get into about 4700 rpm in first gear, it seems to hit a rev limiter? It is at about 5psi of boost or so there. In second gear and up, the "rev limiter" drops to about 4000 rpm.
I thought it was spark blowout and tried gapping down the spark plugs to .025. It didn't make a difference. I turned off overboost protection, and it made no difference.
Any ideas? Also, I'm running MSPNP2. I attached a datalog of two quick pulls.
Thanks!
When I get into about 4700 rpm in first gear, it seems to hit a rev limiter? It is at about 5psi of boost or so there. In second gear and up, the "rev limiter" drops to about 4000 rpm.
I thought it was spark blowout and tried gapping down the spark plugs to .025. It didn't make a difference. I turned off overboost protection, and it made no difference.
Any ideas? Also, I'm running MSPNP2. I attached a datalog of two quick pulls.
Thanks!
#5
Retired Mech Design Engr
iTrader: (3)
Joined: Jan 2013
Posts: 5,012
Total Cats: 859
From: Seneca, SC
I know of at least (2) situations where a replacement engine could have been avoided if overboost had been employed.
Pretty sure it saved my rods when I re-plumbed the EBC incorrectly.
#7
Not a good approach. Overboost protection can save you engine from inadvertent changes in MS settings / popped boost control hoses / etc.
I know of at least (2) situations where a replacement engine could have been avoided if overboost had been employed.
Pretty sure it saved my rods when I re-plumbed the EBC incorrectly.
I know of at least (2) situations where a replacement engine could have been avoided if overboost had been employed.
Pretty sure it saved my rods when I re-plumbed the EBC incorrectly.
#8
It could also be that you've tuned your car based on a low fuel pressure, which could be the pump or fpr.
#9
If they're the real deal, those injectors are good enough for what you're trying to do. I've heard stories of fake rx8 injectors though. If there's any time to upgrade to EV14 injectors (e.g. flowforce or id1000), this would be a good one.
It could also be that you've tuned your car based on a low fuel pressure, which could be the pump or fpr.
It could also be that you've tuned your car based on a low fuel pressure, which could be the pump or fpr.
#12
So I have some updates on my problem.
The car runs great now when it is cold. I can pull all the way through the rev range with 6lbs of boost, but as soon as it is hot, it will not go into boost at all.
As soon as it leaves vacuum and goes into boost it is like it is hitting a wall. The engine cuts out and acts like a rev limiter.
I am thinking it has something to do with my tune.
I also bought some flowforce 640cc injectors and fab9 COPs
Both of these things didn't really make a difference.
The car runs great now when it is cold. I can pull all the way through the rev range with 6lbs of boost, but as soon as it is hot, it will not go into boost at all.
As soon as it leaves vacuum and goes into boost it is like it is hitting a wall. The engine cuts out and acts like a rev limiter.
I am thinking it has something to do with my tune.
I also bought some flowforce 640cc injectors and fab9 COPs
Both of these things didn't really make a difference.
#13
So I have some updates on my problem.
The car runs great now when it is cold. I can pull all the way through the rev range with 6lbs of boost, but as soon as it is hot, it will not go into boost at all.
As soon as it leaves vacuum and goes into boost it is like it is hitting a wall. The engine cuts out and acts like a rev limiter.
I am thinking it has something to do with my tune.
I also bought some flowforce 640cc injectors and fab9 COPs
Both of these things didn't really make a difference.
The car runs great now when it is cold. I can pull all the way through the rev range with 6lbs of boost, but as soon as it is hot, it will not go into boost at all.
As soon as it leaves vacuum and goes into boost it is like it is hitting a wall. The engine cuts out and acts like a rev limiter.
I am thinking it has something to do with my tune.
I also bought some flowforce 640cc injectors and fab9 COPs
Both of these things didn't really make a difference.
#17
The AFR reading in your log isn't making any sense. I believe running VEAL without properly configuring TS for your wideband is creating a nonsensical VE table. Does the display on the wideband match what TS is showing?
Your main issue is that absurd table. It's likely choking on fuel. You need to figure out what setting is causing VEAL to create that monstrosity and then start fresh with a basemap VE table.
#18
Retired Mech Design Engr
iTrader: (3)
Joined: Jan 2013
Posts: 5,012
Total Cats: 859
From: Seneca, SC
First of all: I want to be your parts dealer.
Second: I don't see, in the posted log, the effect you are talking about, but without TPS, it is hard to know your inputs.
Your VE table looks like a Topographical map. Go to Trubokity.com and download the appropriate base map to get some idea of what it should look like, Shape-wise.
No way this will work.
No wait, upon looking at log, there are a few other possible issues:
Have you calibrated your MAT Sensor?
Where is it located?
Have you calibrated your AFR Sensor?
Where is it located?
Does the reading in TS match the reading on the AFR gauge (if you have one).
Is this a 1.6 with a non-variable TPS? Otherwise, have you calibrated you TPS?
Where are you located?
Is there someone you can take the car to so the MS can be set up as a starting point?
Can you describe (pictures would be good) your set-up. What you have done, what the previous owner has done? A build thread?
Maybe go to the Meet and Greet and check in.
Second: I don't see, in the posted log, the effect you are talking about, but without TPS, it is hard to know your inputs.
Your VE table looks like a Topographical map. Go to Trubokity.com and download the appropriate base map to get some idea of what it should look like, Shape-wise.
No way this will work.
No wait, upon looking at log, there are a few other possible issues:
Have you calibrated your MAT Sensor?
Where is it located?
Have you calibrated your AFR Sensor?
Where is it located?
Does the reading in TS match the reading on the AFR gauge (if you have one).
Is this a 1.6 with a non-variable TPS? Otherwise, have you calibrated you TPS?
Where are you located?
Is there someone you can take the car to so the MS can be set up as a starting point?
Can you describe (pictures would be good) your set-up. What you have done, what the previous owner has done? A build thread?
Maybe go to the Meet and Greet and check in.
#19
My bad. Was looking at a different tune. Req fuel looks right.
The AFR reading in your log isn't making any sense. I believe running VEAL without properly configuring TS for your wideband is creating a nonsensical VE table. Does the display on the wideband match what TS is showing?
The AFR reading in your log isn't making any sense. I believe running VEAL without properly configuring TS for your wideband is creating a nonsensical VE table. Does the display on the wideband match what TS is showing?
I think you are right about too much fuel. I pulled my plugs today and they were pretty covered in carbon.
I might just manually tune it instead of relying on VEAL then.
#20
Yeah MAT can't possibly be staying at 70 the entire time. You need to give TS info about your sensors.
https://trubokitty.com/#/tune
Bottom of that page has instructions.
VEAL works fine when you set everything up correctly.
https://trubokitty.com/#/tune
Bottom of that page has instructions.
VEAL works fine when you set everything up correctly.