Looking for recommendations for a cause of a high idle.

Car is a 92 1.6 running a gen 1 MSPNP with a MS2 daughterboard. Boost is provided by a Rotrex maxing out 16PSI at 8k rpm. While it's good fun, I have near constant issues with a high idle, can sit anywhere from 900-2400 during a drive. I'm fairly new to the car (under 1 year) as well as tuning, and inherited the tune from the previous owner, so any recommendations would be great. Tune file is attached.

Also looking for any opinions on the current tune, whether it is fine and safe to run or I should look for a tuner fast.

TIA.

 

I'm no expert, but your VE table doesn't make any sense. I have a 1.8 and smaller 788 injectors, so there will certainly be some differences. Here's my table. I'm running a Rotrex C30-74 at just shy of 10 pounds of boost.
I don't understand how your car can actually run.



You've also got way too much advance in your spark table. Have you checked Trubokitty.com ?

 

Hey, thanks for the response!

I haven't heard of Trubokitty yet, so I'll take a look there.

With the fuel VE table, it does looks confusing as hell, and nothing like what I would expect. It looks lean in some areas, and like it would just be pumping fuel to cool after high RPM. Ignition is a bit all over the shop, no idea what's going on there.

Surprisingly it runs, and well. AFRs are steady and I've had no issues except overheating coil packs. I think it's time I learnt how to tune myself or forked out the money for someone to do it.

 

Unless I'm missing something, this car should be expected to blow up in short order. This ignition table is insanely advanced. You're running more advance at 15 PSI than is usually recommended for a N/A engine (IE 0 PSI/100 KPA)....


Honestly, this doesn't look like it was tuned at all. Overboost protection isn't turned on, the VE table looks really strange (hopefully EGO is helping keep things in line decently), etc....

The swinging idle is likely effected by the base table being pretty weird. There's going to be a huge swing between just 950-1000 RPM.



IMO I wouldn't drive the car anymore aside from heading to a tuner. I'm not a pro by any means, so take it with a grain of salt, but this looks worse than a lot of base tunes to me.

 

Appreciate the advice. I'm starting to wonder how this has been running for so long.

Guess my next step is to look into a local tuner.

 

Do you have a datalog of it running/idling? I'd be curious to see what everything looks like when the car is running.

 

If you want, you can try this. I modified the ignition map and some of the base idle values. I'd still be interested to see a log of the car running/idling, but I think this should be better than what you started with.
Full disclosure, I don't have any first hand experience with a MS1, so use at your own risk.

 

I'm a big fan of the 8000rpm rev limit too. This engine has been sent hard.