02-20-2016, 10:41 PM
Join Date: Nov 2010
Total Cats: 0
Hard/No Start MSPNP and low idle
I just purchased a MSPNP Pro equipped 02 miata with a built motor.
1.9L (85mm pistons) 11:1 compression,
MS3 1.4 release.
Car was tuned with the current engine setup/configuration but a 99 intake manifold instead of a 02 intake manifold.
I bought the car from Texas with the MSPNP Pro attached and drove it up NoVA.
When I bought the car, I purchased it with a factory throttle on it. Starting would take about two seconds of cranking and then it would catch. Cold starts would be a bit rougher, taking 2-4 start events to get it to catch and stay fired. Idle has been rich, running about 12.5 to 1.
I decided after the fact to buy the skunk2 throttle the original owner had on the car as well. I installed the throttle last weekend, and the car drove better, but starting got worse, especially at colder temps, taking part throttle or more to get the car running.
Today, in 65 degree weather, I went to start the car and it wouldn't light off at all. It took a long time (8-10 attempts) to get started, and still ran pig rich. To get it to fire it took part throttle it keep it running once it did start. Letting off the throttle will cause it to stall. I ran warm up enrichment on data log lab but since the curve started halfway through my tune, I am suspect of it as it boosted all colder temps to max value.
Once I got the car warmed up, I tried to auto tune the VE table for idle (logs attached). The AFR got better but that was a wasted effort I think as the idle is still too low
Can someone take a look at my tune & data log and give me some insight. First time with a MSPNP and while the car ran fine for texas settings, something on startup is no good right now.
Once startup is fixed I need to tackle idle because it wants to idle at 500-700 rpm and coming to a stop causes a nasty idle dip and sometimes stall. The original tune file, with no changes is attached. Data log was from when car was running with auto tune on...end of the file shows the idle better but still super low.
Last edited by g_reichow; 02-20-2016 at 11:00 PM.