Remember those Pennzoil commercials? They always said A LARGE PART OF ENGINE WEAR OCCURS AT START UP. Well if that's true, then this is a bad idea for that reason alone. I always believed that the less amount of times you start your car, the better it is for the engine. Who knows if that's true, but I always follow that rule.

 

I think that the point with more engine wear at start up has to do with a cold engine where the oil has drained down to the sump. Starting an engine from cold would cause more wear until the internals were oiled.

Idle off systems are a bit risky from a safety standpoint though. If you were about to be hit by another car, you want to get moving quickly. As a motorcyclist, when at a stoplight I stay in gear, keeping an eye on the rearview mirrors and ready to dump the clutch....not good to be rear-ended on a motorcycle.

 

i wouldn't turn my car off just for a few minutes at a stop light. eventually you're gonna wear out your starter as you repetetively overheat the starter motor from constant cranking. and also the wear on your flywheel, etc. etc.

 

if u turn off ur car and start it at stop lights, ull get 4mpg I ******* swear

 

When you are not moving at all, you are getting ZERO miles per gallon, engine running or not.

 

^^ Yikes! ^^ I didn't know that!

 

your spark plugs will LOVE you if you turn the car off at every red light.

 

the spark plug COMPANY will love you you mean......

 

Omg guys! Global warming is crap! Don't believe Al Gore, he is just trying to sell his propaganda! I say let it all burn!! Rev your renesis to 9k rpm at every red light! But make sure you have an auto so you can put it in neutral

 

Zero divided by zero is not necessarily zero. If you roll forward just the tiniest bit with your engine off, then you've just experienced Infinite MPG!

 

Nowhere as bad as the use of "drug" as the past tense of "drag".

 

hey sorry for bumping this but better than creating a new thread...

in the city i'm frequently stopped for more than a minute so would it put a lot of wear on the starter motor or spark plugs to turn the engine off (assuming its properly warmed up)? I'm not looking for fuel economy or to save the environment... my car just smells like **** at a stoplight (catless lol) and i'd rather not smell it heh...

 

Yes, it would put more wear and tear on everything.

 

All I say is it must work. There would be no reason for manufacturers to install it in new cars if it didn't save gas. As to whether doing it youself manually works compared to a car with start-stop technology is an open question.

Regardless, we have frustrating light nearby that takes EXACTLY two minutes to change in your favor, regardless of traffic. I turn the car off.

 

Ummn, then put your convertor back on?
Not really that hard to see the cause and effect in this case.

BC.

 

The biggest problem manufacturers ran into with start/stop on normal cars is reduced battery life. Hybrids can deal with numerous high-current starts, lead-acid batteries cannot. This is one reason Mazda is going to a capacitor-storage system. Another solution is to not use the starter at all, but rather to stop the engine with one cylinder ready to fire. Then with DI, all that's required is a squirt of fuel and a spark to start - the starter is not used at all.

 

The only company currently doing the last way is Mazda with its SiSS .

 

Yeah it's not like I hadn't thought of that... it's just for track weekends I remove it so I don't melt it. I'm still just curious about how much wear the engine is taking if you're starting up a fully warmed up engine.

A lot of the modern porsches shut off the engine at red lights but I think they use the method described above by using 1 cylinder to fire. I guess my bottom line question is... does it wear out a rotary engine more when starting compared to a traditional piston engine?

edit: actually I guess porsche just puts in a beefier starter motor

 

I guess turning the engine off would definitely preserve gas, how much would be the question.

The 2 rotor engine in the eight is only 1.3 liter too, so as long as its just at idle with stock injectors and fuel pump, it should be really good in terms of preserving gas... I think, Right? I dunno.

Oh and on a side note: the Prius scares me, its quiet...TOO quiet

 

You are lacking in the intelligence department aren't you

 

I rented an M7 (pretty sure it was an M7) in Germany at the end of last year... that diesel beast would shutdown at every red light... first time it happened I thought I killed the car!

 

While you may save gas while sitting at the light...don't you use more gas to fire an engine than just sitting at idle? At best I would hope to break even.

 

Why would you do that on every stop lights...geesh