Driving before warmed up

[Banshee]

I noticed that if I drive before the car is warmed up, I seem to get into boost much eaiser (lot less pedal effort), but there's a lack of power, stumbling. My theory is that the computer is fully retarding the timing. Am I correct? I don't want to go into boost, but sometimes it just happens with minimal pedal travel.

[Tom @ Fast Forward]

If it is a 99/00, the problem is the O2 sensor warming up and is probably ready to drive in 2 minutes. I drive my 99 about 10 seconds after it starts. If it is an 01-05, you have the first 2 minutes of O2 warmup AND the oil needs to get up to temp. The VVT works on oil pressure/flow and cold oil doesn't move very well in the small tube to the VVT. The ECU has a hard enough time making VVT work right when the oil is warm but cold, it just doesn't do well.

There is no harm done in either case as it simply runs rich for that period of time.

[99mx5]

Same here, I fire it up and just go.

[ThomS]

If it is a 99/00, the problem is the O2 sensor warming up and is probably ready to drive in 2 minutes. I drive my 99 about 10 seconds after it starts. If it is an 01-05, you have the first 2 minutes of O2 warmup AND the oil needs to get up to temp. The VVT works on oil pressure/flow and cold oil doesn't move very well in the small tube to the VVT. The ECU has a hard enough time making VVT work right when the oil is warm but cold, it just doesn't do well.

There is no harm done in either case as it simply runs rich for that period of time.

Tom I understand what you are saying here, but why didn't my 02 ever do this before I had Sc installed? I just adjusted my driving habits and no problems.

[Tom @ Fast Forward]

Thom, the 01-05 before the kit install, had the VTCS and the computer used it to compensate for the cold starting conditions. With the kit, you took the VTCS off and the computer still thinks it is there. the 'penalty' for all that fun is 90 seconds of idle funkiness. :) I did find with my 05 on a cold morning that, if I got on it a bit, it went great during that first 90 seconds or so. it was idle and just off idle that were problematic. On the other hand, letting a cold engine idle for 90 seconds on a cold morning isn't a bad thing either.

[chuckerants]

With my 99, there is about a mile of 30 MPH driving before I get to the main road and it's normal driving for me and no warmup.

[Tom @ Fast Forward]

Yes but you live in Phoenix where a cold winter morning is 80F. ;)

[lds2002black]

On my 2002 it is a little "stubborn" until the water temp hits 145º which is where I believe it goes closed loop. This all clears up by the first street I pass going out of the subdivision so not a big deal (or worth attempting any fix on my part). Maybe a 115mm pulley would solve the problem?:devil2:

[Tom @ Fast Forward]

Or 130mm for complete cure. :devil:

[lds2002black]

I guess I'm a little shy on a 130 mm pulley due to the reliability I've had so far. I assume the belt also has to change length with a 115? Anything elese besides get F/A set again?

[ThomS]

Thom, the 01-05 before the kit install, had the VTCS and the computer used it to compensate for the cold starting conditions. With the kit, you took the VTCS off and the computer still thinks it is there. the 'penalty' for all that fun is 90 seconds of idle funkiness. :) I did find with my 05 on a cold morning that, if I got on it a bit, it went great during that first 90 seconds or so. it was idle and just off idle that were problematic. On the other hand, letting a cold engine idle for 90 seconds on a cold morning isn't a bad thing either.

Now I do remember that.. Amd you are right If I let it idle for about 1 or 2 minutes it runs just fine.

The car is still running great and no codes at all over 1000 miles since last code.

[Tom @ Fast Forward]

I was being a bit facetious :). I don't typically recommed the larger pulleys for the 01-05. You could probably get away with a 110mm and possibly the 115mm but that would be my limit for recommendation. What fuel do you have locally? Have you had any ping issues? It is that 10:1 compression that makes that engine not like a lot of boost. I guess I would also recommend the timing card for sure if you up the pulley.


I guess I'm a little shy on a 130 mm pulley due to the reliability I've had so far. I assume the belt also has to change length with a 115? Anything elese besides get F/A set again?

[lds2002black]

We have 93 octane (now with 10% ethonal). I agree that with this high compression motor the boost I get now is probably in the upper range of not having motor issues. At least I know where I "might" be able to go if I want to increase the risk ... Thanks!!