Hello all, I have a 2003 mach 1 with auto trans. Upon start up I think it idles high, going to about 1200 rpms. If i immediately put it into drive, it clunks into gear somewhat abrubtly due to the high rpms. If i let the car idle in park upon start up, it eventually goes down in rpms (700-800) after about two minutes. To me, this is annoying (its a new 2003 car, not a 1973 mach1!!!) and unacceptable (maybe damaging the trans after a while). I recently had it back to the dealership for service and they ran it in the computer and found no problems. The quote from the service manager was "this is the way these cars run. it has a high compression motor and it just takes a little longer for the motor to heat up". Basicaly telling me i have to wait for it to heat up and idle down. Is this idling typical of all 2003 mach 1's, specifically those with auto trans? I appreciate any body else's comments....
i think he meant that the car "warms up" to the point where the idle goes down. so I guess he is referring to operating temperature, which may be affected by the high compression and the fact it might take longer ?
It sounds like the PCM is operating within it's programmed parameters...... I'm not sure what you are expecting from the car, but it sounds like you're setting yourself up for disappointment. What is the mileage on the car, BTW? Even though they are computer controlled, they are still basically mechanical devices and need some time to gather up their equalibrium.
Two minutes isn't out of the question, especially if you live in an area that is less than tropical. The materials, manufacturing techniques and oil delivery systems may require some of us to rethink those things we used to know . Anyway.... a cold motor is a cold motor - whether it is 1973 or 2003, and cold motors need to build some warmth to aid in fuel distribution and combustion.
I've seen this type of question posted for just about every make of Mustang. That 2 minute "high idle" is your warm up period. My '01 Vert does the same and I already knew it would do that. I just wait until the idle drops below the 1k mark then put it in gear. Putting it in gear at that high idle period will cause your tranny to wear out quicker. Give yourself more time to let the car idle down before moving.
I also have an 03 Mach with auto. Mine comes off the high idle in 20-30 seconds..... regardless of outdoor temperatures. I'd have it looked at again, and let the dealer keep it overnight if necessary so they can observe a cold start. Believe it or not...not every problem is computer related and this could be a simple as a weak throttle control spring.
In the meantime, let the car run for as long as it needs to return to normal idle, maybe try "kicking" the gas pedal to force the throttle control to a normal position. Shifting into gear at 1200 rpm's is NOT good for the drivetrain and could cause you unbelievable grief.
A great source of information is the Mach 1 Registry which is expressly for new Mach owners to share info and experiences.
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'd bet that there is some info there that will you identify the problem andrecommend a fix. Good Luck!
I have a 95 Buick with an LT1 motor and automatic tranny. When it's idling high at cold, I can go ahead and put it in gear and the computer lowers the idle before the tranny engages. I think that's pretty cool. This happens as soon as I start "moving" the shifter, but still not at the gear I want it in.
----------------- Jim '88 LX 5.0 (now in car heaven) '89 LX 5.0 vert '99 GT 35th Anniversery Edition - Silver Mods to date - Relocated trunk release to drivers side, shortened throttle cable.
The two worst things you can do to a cold engine are:
1) "Kicking" the throttle
2) Letting the engine sit and idle
The best things you can do for a cold engine are:
1) After start up, let it idle for no more than _one_ minute
2) Drive it easy, keeping the revs down, for about the first 15 minutes, or until the oil warms up. (Note: It takes longer for the engine's oil to warm up than its coolant. So your car's temperature gauge isn't a true indicator.)
Back when I had my '67 Galaxie 500 (289 + FMX) I had to adjust the choke in the winter, as it was not running to my satisfaction. I got it tuned to the point where I was idling at ~550 RPM warm and not more than ~600 RPM cold. That's in weather below freezing. I got the car to the point where I could go out in the morning with the ambient temp below freezing, give it one pump of the gas pedal, fire it up, and immediately drive away. The car ran perfectly smooth without so much as a stumble while warming up. Oh course I didn't regularly drive away without letting it warm up for a minute or two, but if I was running late or there was an emergency I wanted to be able to go right away.
The engine had ~195,000 original miles at the time and was all stock except for a slightly larger carb (1.23 venturi Autolite 2100 as opposed to the
1.08 venturi stock carb). A Galaxie is a heavy car at over 3,600 lbs, so it's a pretty big load for a little 289 too. Despite that it would never stumble or hesitate. My '68 Galaxie 500 with a 302 I couldn't get to idle that low when cold but that was because my uncle abused the hell out of it and it had virtually no compression on one cylinder and very low compression on another. What I would like to know is why can't (won't?) they make cars that run like that?
Personally I don't believe an engine should be revved too high when cold, for it's longevity. The obscenely high RPM cold idle most new cars have is ridiculous. My '86 Calais has a cold idle ~2000 RPM and works it's way down from there. When I first start it up it goes to 2200 and I have to kick the throttle to get it to drop right away. My old '86 Prelude (UGH! Big mistake going foreign for that beater) would idle at over 2000 when cold, and I would have to kick the throttle to bring it down a little. The Honda was a dual carb and the Olds is fuel injected. I don't even think a 4 banger had to idle that high, so I don't see why a V8 should be at 1200 RPM when cold, or higher for some engines/cars. Maybe I'm just weird, but I don't see why an engine should be idling significantly higher when cold than when hot. If my old 289 could do it with simple '60s technology I don't see why it can't be done on today's engines with modern technology.
It's not fair to just say"my engine didn't do it why should yours". There are different performance levels to consider. I don't own a Mach1 so I wouldn't know for sure, but that 281ci motor is making around 320hp right? On an NA motor that probably means a bit of a cam. Cammed cars exagerate cold running problems. When a motor is cold the fuel does not atomize as well. When it hits the cold metal ports on the head it condenses and "falls out" making the mixture falsely lean. This is just a matter of physics. That's what chokes and comuters do is make the mixture rich to compensate. The motor does not have to come up to running temp but you have to give it a little time generate some heat. Probably less than a minute. Just to demonstrate using extremes, I have a small block that was highly modified. If I started it cold in the winter it would stall at anything under 1300 RPMS. Even hot it idled very rough at 1000. There was absolutely nothing wrong with this motor. Again this is an extreme I'm just saying I couldn't go and compare it to my 125hp Jeep and think my small block should idle like my Jeep.
The purpose of the high idle is to warm up the engine as fast as possible. Your assertion that you normally allow the car to warm up before driving suggest that you buy into the old myth that this is somehow beneficial. Engine designers tell us that a car suffers it's greatest wear during warm-up time. The faster it warms up, the less wear it experiences. To minimize wear, fire it up and drive it right away to reach operating temp in the quickest time.
So you are saying in the winter I should not have fired up the Gal until _after_ I cleared the snow off of her? Typically in the morning I would start the Gal and let her idle with the defroster on full blast high heat while I cleared the snow, and after the snow/ice was cleared I would drive away. Sometimes it only took 30 seconds or so, other times it took a couple minutes if we got a lot of snow. I always thought that was the best way to do it as it lets the engine warm a little before putting a load on it, and also warms the coolant to a point where it will actually make some heat to be effective in defrosting the windshield. Not to mention getting the temperature inside the car a little more hopitable.
The other benefit of letting it warm up was that the poor old FMX trans would not slip on the first 2-3 shift if I let it warm up for a couple minutes. When the temperature neared freezing it would always slip on the first 2-3 shift if I didn't let it warm up first either by idling or by forcing the trans to stay in second gear for the first minute or so of the drive. I hear those transmissions only have so many 2-3 shifts in them. I suppose a little slippage before warming up in near freezing weather isn't bad for a 36 year old transmission with 202,000+ miles on it.
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