99 Corolla - Hesitation when cold

I'm sorry, I have to put my 2cents in. Think about this. When you wake up in the morning do you jump out of bed running or do you take time to stretch and rub your eyes and slowly wake up? Why then, would you accelerate hard with a cold engine? It can't possibly respond the same as a warm engine. The computer has to scramble to figure out a proper fuel/air ratio, your oil may be like syrup and lacking upper engine lubrication, belts and hoses will be stiff, along with transmission, differential, etc. It's kinda like trying to spring a 2,400 pound frozen block to life. I'm not going to go into the great debate on warming up your engine etc. except to say the following.

There will be a lack of upper engine lubrication simply because your syrupy oil has all leaked down into the oil pan over night and can't efficiently get pumped back up there until its warmer. there are adnauseum debates about engine damage. . .

In the old days of carbeurators it was necessary to "warm up" your engine before you could drive away because proper fuel/air ratio depended on choke control and a heat riser valve operated with heat from the manifold. Never mind hesitation, you often had no ability to even drive away depending on how cold the engine was. Nowadays, with fuel injection and computer control (goodbye Carbeurators!) the engine is much more tolerant of cold starts because the computer does its best to optimize fuel/air ratio according to engine load.

Standard operating procedure in my extremely cold in winter part of the country is to start the car, let it run for only a couple of minutes and then DRIVE AWAY SLOWLY, at least until the temperature guage starts to move. By then you should have close to normal operating performance.

It also really helps if you have a block heater and you are able to plug the car in to keep the oil and coolant temperatures from hitting rock bottom overnight.

I guess you guys jumped to the conclusion that I am a Corolla abuser. Please don't report me to the authorities. Just kidding.

To be fair, I should have clarified a little more.

CASE 1 (2 TIMES):
Leave work about 9:00 PM, temp approx 40 degrees.
Start car
Let idle about 20 seconds
Drive about 1/2 mile at 20 MPH.
Wait at stop light 1-2 minutes
Drive 1/2 mile with moderate acceleration to 35-40
Wait at stoplight less than 1 minute.
Get on freeway via clover leaf onramp, coming out of clover leaf curve at 35-40 MPH I then get on it and it hesitates as if the engine will stall (no power). The hesitation is less than a second. I let off the gas and everything comes back fine, full power.

CASE 2 (1 TIME):
Start car in garage, outside temp 35-40 degrees.
Let idle while i go fill the commuter cup with coffee.
Back car out of garage, manually close garage door (auto opener broken).
Drive at 25 MPH for approx 1 mile.
Drive at approx 50 MPH for 2 miles.
Enter highway, get on accelerator, hesitation for less than 1 second.

I have commuted to work about 1,400 times in the last 7 years (different temperatures). No hesitation until the last 2 weeks. In both cases, the temperature guage is midrange between cold and normal operating temperature. Air from the heater is already starting to warm up.

In the last two months I have posted threads on my experiences changing my cars struts and removing the starter. I provided some detailed tips not mentioned in the Haynes manual. I would appreciate some help.

Thanks,

Modestobulldog. I apologise for jumping to conclusions about the situation. The additional information really helps.

Actually I think the cold engine is only accentuating something else that may be wrong. Here's an experience I've had.

When I first got my '98 rolla (used) it would hesitate on moderately hard acceleration and much worse if I really stomped it. It was worse when it was cold but still definitely there when it was at full operating temp. I actually thought it was the auto tranny at first. but then I read a post about diligently replacing the spark plugs as these engines are very sensitive to that.

Sure enough I looked at the plugs and found the previous owner had installed Bosch Platinums which were not recommended by others. I went to the dealership and picked up their recommended normal cheap (Denso I think) plugs, put them in, and the problem disappeared completely. After putting about another 80,000km on the car I noticed similar symptoms and some minor rough idle/missing. I replaced the plugs again and also this time the wires. The car has 190,000km on it now and runs great. The plugs and wires fixed everything right up. This was my experience. It may be something you could look at if you haven't already.