StallionStarion Posted October 6, 2022 Report Share Posted October 6, 2022 (edited) Hello everyone! My name is Lukas and I recently picked up a 1987 Mitsubishi Starion! I ended up getting it off auction for ridiculously cheap because I love old Japanese cars, especially turbo ones 😉 The one I picked up ended up having an upgraded turbo/exhaust manifold and a GM maf with a maf translator with some upgraded sway bars. I currently don’t have pictures of it (I know, how could I not have pictures of this beautiful machine but I will get some and upload them) I have got the car running and everything but the current issues I’m having are that the car runs rough when it’s cold, basically doesn’t want to idle until it warms up. The car doesn’t want to go into much boost if the vacuum like from the housing to the internal waste gate is connected (probably 2-3 psi) and with it off the boost gauge goes up to around 6-7 psi. Now I don’t know what it’s supposed to be from factory because I got it with a different turbo already but that’s what I have deduced so far (maybe wastegate problem).     Next is that my head lights and tail lights do not work. The head lights go up and down but do not turn on, same with the tail lights. Brake lights and turn signals all work, just not the lights themselves. I plan on putting an AFR gauge and a boost gauge soon (already have the gauges just need the time to wire everything in) for more information and see how safe if it with the air fuel ratio. I also have a megasquirt that I had for a turbo Miata build I had so that is also an option! Anyway, thank you for reading! Glad to join the community, and suggestions and input are much appreciated! Wish you all good luck! Edited October 6, 2022 by StallionStarion Quote Link to comment Share on other sites More sharing options...
psu_Crash Posted October 6, 2022 Report Share Posted October 6, 2022 (edited) Sounds like a coolant temp sensor issue at cold start, maybe combined with the Idle Speed Controller not doing it's thing. In the FAQ there is a walkthrough on resetting the ICS. You can also test the coolant temp sensors. Yes there is more that one  Take a look through the service manuals here for specs on the sensors. http://starquestgarage.com/  Welcome Aboard!!  P.S. I'm a big megasquirt fan. My advice is ditch that MAF-T and MS it. Then you have some real diagnostic abilities. Edited October 6, 2022 by psu_Crash Quote Link to comment Share on other sites More sharing options...
tux Posted October 6, 2022 Report Share Posted October 6, 2022 Welcome to the club and congrats on your purchase! Starquestgarage.com is going to have factory service manuals available, not for the 87, unfortunately but looking between the 88 and 86 manuals you should get a feel for it. Check the electrical section of either the 86 or 88 FSMs for help with the taillights and headlights. I agree w/ ditching the MAF-T and putting in another ECU. I went AEM, but I don't recommend it as you'll find more people to help you with Megasquirt, even a plug 'n' play option  Quote Link to comment Share on other sites More sharing options...
StallionStarion Posted October 6, 2022 Author Report Share Posted October 6, 2022 3 minutes ago, tux said: I agree w/ ditching the MAF-T and putting in another ECU. I went AEM, but I don't recommend it as you'll find more people to help you with Megasquirt, even a plug 'n' play option  There’s a plug n play option for the megasquirt? Quote Link to comment Share on other sites More sharing options...
860QuestTuner Posted October 8, 2022 Report Share Posted October 8, 2022 Welcome to the club. The electrical part of the manual will really help. The fusible links next to battery would be first to check. The factory boost gauge is not reliable and the stock wastegate will only do 7 or 8 unless it has a 88 /89 style or a boost controller. There is also a possible leak at turbo flange or piping. Quote Link to comment Share on other sites More sharing options...
tux Posted October 9, 2022 Report Share Posted October 9, 2022 On 10/6/2022 at 2:21 PM, StallionStarion said: There’s a plug n play option for the megasquirt? Yeah. I forgot which user was selling them though. Quote Link to comment Share on other sites More sharing options...
GoldStar Posted October 9, 2022 Report Share Posted October 9, 2022 1 hour ago, tux said: Yeah. I forgot which user was selling them though. Not sure about a megasquirt, but MotoCam360 just recently took over Scotty's work from DIYAutoTune: https://www.motocam360.com/products/starquest/product/121-mc360-stand-alone-ecu Quote Link to comment Share on other sites More sharing options...
tux Posted October 9, 2022 Report Share Posted October 9, 2022 Ah yes, it was Scotty. Â And yes it's an ms Quote Link to comment Share on other sites More sharing options...
scott87star Posted October 13, 2022 Report Share Posted October 13, 2022 I did build plug and play systems, or as plug and play as it could be since you still had to add a MAP sensor and a real IAT sensor, don’t recommend them when a PO has already hacked the wiring.  Best to get with Tim and pick up the stand alone with a fresh wire harness, save you lots of time and frustration chasing 35 year old wire harness demons. Quote Link to comment Share on other sites More sharing options...
BlueCuda Posted October 13, 2022 Report Share Posted October 13, 2022 On 10/8/2022 at 8:32 PM, GoldStar said: Not sure about a megasquirt, but MotoCam360 just recently took over Scotty's work from DIYAutoTune: https://www.motocam360.com/products/starquest/product/121-mc360-stand-alone-ecu He won't say its megasquirt, I had asked on a facebook post awhile back. But I am real sure its Megasquirt. Megasquirt is good stuff though, I have a MS3X+Microsquirt on my other car. It has been rock solid for 7 years now.  Quote Link to comment Share on other sites More sharing options...
scott87star Posted October 13, 2022 Report Share Posted October 13, 2022 It’s based on an MS2 module but has an additional support board that includes a beefed up 5V supply, onboard MAP and baro sensors and a plug in module for onboard wide band O2.  We also included a space for Bluetooth and/or WiFi.  It’s great value for the money and it can run the G54 fully sequential ignition and injection if you swap to an early 90’s optical distributor for the rpm input. Quote Link to comment Share on other sites More sharing options...
BlueCuda Posted October 13, 2022 Report Share Posted October 13, 2022 I agree it does look like a great value.  Quote Link to comment Share on other sites More sharing options...
StallionStarion Posted October 14, 2022 Author Report Share Posted October 14, 2022 22 hours ago, scott87star said: don’t recommend them when a PO has already hacked the wiring.  Best to get with Tim and pick up the stand alone with a fresh wire harness, save you lots of time and frustration chasing 35 year old wire harness demons I’m glad that the PO didn’t touch the wire harness. Even the radio harness is fresh. All I need is a jumper harness from stock starion wire harness to megasquirt, not a whole ecu and wire harness. Does something like that even exist for these cars? Quote Link to comment Share on other sites More sharing options...
scott87star Posted October 15, 2022 Report Share Posted October 15, 2022 I have made them, you just need another ECU to scavenge the connectors from.  Doesn’t matter what year, the connectors are all the same, only the mounting tab position changed. Quote Link to comment Share on other sites More sharing options...
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