Off boost stumble
05-06-2018, 07:49 PM
#16
Rennlist Member
Thread Starter
I was under the impression that the only difference in sensors etc. is that the O2 sensor is not used in open loop. I thought everything else was used in both open and closed.
05-06-2018, 09:32 PM
#17
Drifting
Ok the five main sensors to make an engine run are MAF/speed density(whichever applicable), Intake air temp sensor, Coolant temp sensor, Throttle position sensor, Crankshaft position sensor. Other secondary sensors are the Knock sensor, Oxygen sensor, Camshaft position sensor and RPM sensor. Switches are the idle position switch, Air conditioner switch, and coolant switchs for the fan and evap system. I forgot an important switch, the ignition switch.
Last edited by Humboldtgrin; 05-07-2018 at 08:51 PM.
05-06-2018, 09:57 PM
#18
Rennlist Member
If you disconnect the o2 sensor, the car will just run off the base maps without constantly fine-tuning the AFR to dither around 14.7 (when on the non-WOT maps). The car shouldn't really run much differently with it disconnected, maybe a bit richer, but nothing dramatic. If your car starts running much leaner, or much richer, than with the o2 sensor, that's a clue that the o2 closed-loop system was helping to mask a problem. Depending on whether it's rich or lean, it may help you further diagnose where to look. It's not like there is one set of sensors that are used when the car is in closed loop and a different set that are used in open loop (other than the o2 not being used in open loop).
05-06-2018, 11:39 PM
#19
Rennlist Member
Thread Starter
Went out for a drive tonight and could not get it to stumble consistently.
It did stumble a couple of times after I shut it off for 5 minutes and then started out again. It actually stalled once. After that it ran normal.
It did stumble a couple of times after I shut it off for 5 minutes and then started out again. It actually stalled once. After that it ran normal.
05-07-2018, 03:39 PM
#20
Rennlist Member
you can drive with the TPS disconnected since you have M-Tune you have a map sensor which compensates, I ran into a similar issue way back and Rogue suggested it and stated that it should be fine. I wouldn't do it as a permanent solution of course but as a means until you have figure out the issue.
05-15-2018, 11:05 PM
#21
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Thread Starter
The shop that services my car said that the TPS tested good and they don’t want to spend more time doing diagnostics.
I am going to order a new battery for my netbook so I can do some data logging.
Can any of you guys help interpret the logs for me once I have logged during the stumble?
I am going to order a new battery for my netbook so I can do some data logging.
Can any of you guys help interpret the logs for me once I have logged during the stumble?
05-16-2018, 03:08 AM
#22
Professional Hoon
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The shop that services my car said that the TPS tested good and they don’t want to spend more time doing diagnostics.
I am going to order a new battery for my netbook so I can do some data logging.
Can any of you guys help interpret the logs for me once I have logged during the stumble?
I am going to order a new battery for my netbook so I can do some data logging.
Can any of you guys help interpret the logs for me once I have logged during the stumble?
05-18-2018, 08:00 AM
#23
Drifting
What did they test the TPS with? If it was a digital multimeter then test it again but with an analog ohm meter (one with a sweeping neddle). Or an oscilloscope.
05-23-2018, 07:05 PM
#24
I am as puzzled by my statement as you are. Hoping that my alter-ego responds. I feel like I have a memory of something I can't quite grab onto - like an ever receding shoreline just out of reach. I don't know what it means but the second it comes to me I will report back in!
05-29-2018, 11:26 PM
#25
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Thread Starter
Crap MAP signal
Crap MAP signal
05-29-2018, 11:27 PM
#26
Rennlist Member
Thread Starter
This was taken at idle when it started running like crap.
05-29-2018, 11:30 PM
#27
Rennlist Member
Thread Starter
Running normal here
Normal
This is how it was running prior to everything getting wonky as shown 2 posts above.
05-30-2018, 12:17 AM
#29
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Thread Starter
05-30-2018, 12:25 AM
#30
Rennlist Member
Thread Starter
If it isn’t a bad MAP signal then what would be causing my MAP to be 25.68 at idle?