I bought my 93 MX-3GS (5-speed manual) new and have driven less than 120,000 miles. It is in pretty good condition, but has had an idle problem for several years. Until recently, the idle would drop to almost a stall, then rev back up when in neutral and foot off of the clutch (when in 1st gear, idle was fine). I replaced the PCV valve a month ago and now the idle revs & drops almost to stall when stopped:foot on or off clutch, when in or not in gear.

I guess my first question issince it has been so long since it's idled correctly, what is the normal idle rpm for my car? Second question, what should my mechanic look for when trying to diagnose &fix this problem?

Thanks for any advise!

 

you might want to check out your vacuum system its what im trying to fix on mine

 

Hey there, it could be a number of things but always start with the simplest and work your way up. First thing is, it sounds like it could defenetly be a vaccume leak but usually with a vaccume leak it wont rev up mostly just down. You need to check your compression for sure that's what I would do. To check for a vaccume leak get a hand propane torch and slowly sweep it above your engine while your car is running if at any time it sucks it in that's where your leak is. The last thing is your cooling system. I had a similar problem with my mx3, when I would be in nuetral my rpm would rev up and down and up and down. It's because it was overheating, I had a leak in my water pump gasket. By the way the normal RPM is about 1.5 grand in nuetral. GOOD LUCK!

 

just a thought, have you checked the air intake duct as this can affect the idle if it has any cracks or splits, the duct is prone to deteriation due to the vibration of the engine.

 

hi guys. Im new and just got my mx-3 today. 95 1.6l auto. but when at a stopsign or stoplight in gear. it idles less than id say 500. (good bit below 1k) but doesnt feel like its trying to stall. it shakes the steering wheel. Last think I need is another car with cooling probloms. I am going to compression check it. but I was wondering if the 1.6l happened to idle low?

 

hey is there anyway anyone has the time or patience to completely break down how to check everything that could be causing low idling/stallin on an automatic 95 mx3. Any help would be great thanks.