Hello,
I have a 1992 turbo miata that is using megasquirt. I am using the free version of tuner studio and have already loaded the miata base map to my megasquirt pnp 2. I made a few small adjustments to account for my turbo and was able to get the car to start and idle. However, when the car runs it is very rich. The spark plugs are good, but they obviously were getting too much fuel. I checked the injectors to make sure they are working as they should and they appeared to be good. As I watched the tuner studio gauges and I noticed that my pulsewidth was sitting at around 34 ms. Also, I have installed a intake air temperature sensor, so I changed my megasquirt settings from coolant temperature sensor to air temperature sensor. However, when I come back to it the settings still seem to be set as coolant temperature sensor. I have changed from the stock 230cc injectors to 550cc injectors. I have the required fuel set at 5.2 and the base reference pulsewidth is at 5.23. My problem right now is that the car is running too rich. When I rev the engine it does seem to clear out some, so I don't know if its idle related. I am new to this and would greatly appreciate any help you guys can give me. I will also upload my current tune on my miata.

Thanks,
Daniel

 

What is your wideband reading?

 

Which 550cc injectors are you using? Did you get the startup base map from diyautotune? Was it working okay before you installed bigger injectors? Can you adjust required fuel (maybe a half point at a time) and get it to run better? A datalog would be helpful.

 

Tunerstudio will not remember your thermistor setting; however the megasquirt will.
What is your AFR? cold engines usually run rich (12:1 to 14:1) in the warmup sequence
Have you tried taking data logs and run VE analyze in Mega Log Viewer?

https://www.diyautotune.com/support/...tartup-tuning/
Read • 'Getting It Tuned'
• 'Too much fuel even with zero cranking pulse width'

 

Hey guys thanks for the quick responses. I am using 550cc rx7 turbo injectors with the purple top. I double checked on my timing and got that all figured out, but did not seem to help much. As I was originally thinking the problem could be injector related I changed back to the original miata injectors and went back to the 11.2 req fuel. That did not solve my fuel issue as raw fuel was still coming out the tailpipe. However, it did cause the engine to eliminate some of the pulsing. I believe I have a leak on the exhaust side of the turbo where the clamp hooks the turbo to the down pipe. What symptoms could arise from that? I am planning on wrapping it with some exhaust heat wrap. When in the start up/warm up the AFR begins up around 14, but quickly lowers down to 10 or little less. I took the car for a short ride around the block and the engine was still rich until I believe I was nearly back home (The AFR would sit about 10.5). When I would try to give it a little gas the engine would quickly start to die as though it was fuel starved, which doesn't make sense. When I got back the turbo was very hot and smoking. As a result, I probably wont take it for another ride until I get some of this stuff ironed out; I will just go through the warm up process.

I have tried using data logs, but because I have have the free version of Tuner Studio I could only take very short logs. I got the base tune from DIY autotune using MS2E v3.3.1a MSPNP2-MM9093. I was using the Exhaust Gas Oxygen2 gauge on the megasquirt hoping that would show me the wideband reading. It was at a pretty constant .2 volts, but that wideband would actually show me oxygen to fuel ratio right? So, I'll have to go back and look through all my gauges and find the right one. Here is my current tune.

Thanks again guys.

 

Please let me know if my tune is not uploading.