I’m not a mechanic, but I worked with them. I’m also not completely certain if you’re telling us that the car stutters when you’re decelerating, say at a stop sign, or if it’s stuttering when you let the foot off the brake when you start off, or both. This is, no doubt, a problem on my part, not yours.
I’m taking these OTC sleeping pills, you see. But I’m trying to help.
Whatever the problem is, you may be able to avoid it in the same way in which unscrupulous mechanics fix idle problems–with a flathead screwdriver and a lot of cohones which, IMHO, oughta be kicked a little more often if they’re pulling stuff like that. But there’s a big caveat, so don’t miss my last paragraph.
I see that there is a known problem with MX-6 throttle position sensors. This brings up the interesting possibility that there may be a behavioral reason for the problem, if I understand that page correctly (and you’d better not trust me).
Someone may have traced a “memory” into your car’s throttle sensor system and you’re annoying the car by driving it differently. Purely out of curiosity, do you share your car with someone who drives it more than you do? Or–get this–you may have really picked it up used from a little old lady who drove the same route to church on Sundays.
Anyway, that’s a three-pointer from the half line. On to the quick fix.
Idle speed problems can sometimes be whisked away (perhaps temporarily) by raising the idle speed of the car. It can fix the problem if the idle is just too darned low, but it can also mask other problems.
First, find the idle adjust. That’s your biggest problem since I can’t find it in a quick Google search. Second, take a flathead screwdriver and, with proper safety precautions like no long hair hanging over the belts and the shot-glass of Bacardi 151 safely resting on the oily rags on the workbench, adjust the idle screw upward until the car stops stuttering. I think the '93 MX-6 had a tach so you might be able to test the car in park–otherwise, you have to go by feel. I’ve seen relatively good cars running with idle speeds above 1100, but keep in mind that the higher the idle rpm, the faster the car is going to putter along at idle while in drive–we took one 450 SL in trade which “idled” at about 25 MPH.
Do not have a girlfriend or wife who just busted you for cheating keep the car at rest with her foot on the brake and with the car in drive while you attempt this, unless you want to be the last trophy to grace the garage wall. Instead, adjust the idle in park and take the car for a drive to see if it helped.
If it doesn’t, you’ll have excluded one obvious quick-fix which a disreputable mechanic might attempt to screw you over with by saying he had to replace your transmission rekinebriator regulator sensor or something. If it does work, you have to decide if you can live with your automatic straining at the brakes a little more than it did, and you’ll always wonder if the problem was just that the idle was too low to drag the car around, or if you had a real problem.
I’m pretty sure that the 1993 MX-6 was also virtually the same car engine-wise as that year’s Ford Probe, so you may have two venues for research.
And here’s the caveat: Did you have the same mechanic for the Celica and the MX-6? Your mechanic may well be completely honest and decent, but he may be also trying to do you a favor by keeping your idle speed low, quiet, and more fuel efficient. If that’s the case, just tell the guy next time that you’re having some stuttering problems at idle and can he please boost it up a touch. Your mechanic ain’t no dummy: he sets your idle speed while the car is in park, and probably doesn’t test it much while just in drive; I’d forgive the guy if he hasn’t spent the last fourteen years charging you for rekinebriators.
And you know what’s the worst about this post? I’m probably completely wrong. But it’s the annoying little things which look like big things which lead to temptation on the part of mechanics, so it can’t hurt to check it out.
Please keep trying guys…