Annoying cold start 02 STI
 

2002 JDM STI
** ** * * ** **
Thought my car was sorted but hardly use it anymore and have a tedious cold start problem still. Did have a constant rough lumpy idle issue and found the n/s inlet cam was 1 tooth advanced when all else was timed up. I sorted that and car was nice afterwards, trouble is haven't used it for ages and it seems it's still poor going from cold.

Only get in it once or maybe twice a week now and from it's first start it's a pain in the arse! Fire it up and it runs lumpy and it appears to be chucking too much fuel in, just feels choked up. It'll also go to stall if I drive straight off and get to a junction 100 yds away. Really bogs down when you go to pull away and have to rev it to clear it. Once I've done a mile it's ok, runs smoother etc, pulls really well.

I just bought a new coolant sensor and reset ecu but it's still the same!

Only thing I did get with ecuexplorer was a fault with the o2 sensor, think it said power or heater fault (was a while ago and I've had no time for this car since my new job)

Compression not low (checked)

Only other prob I had last couple of times is the iscv is sticking.

Any chance a faulty or non working heater for the o2 sensor would do this to the car when cold?

I get a really lumpy idle from really cold (ie left overnight) and I've been told that the AVCS on the two banks are slightly out of sync. Once the car warms up they sync up and it's fine, but I get lumpy idle and a slight smell of fuel when it's cold.

It's quite possible that could be my problem too because I did have avcs advance on n/s cam when the o/s was 0.

When I found out the cambelt was wrong I assumed that had sorted the avcs issue. Ecuexplorer won't connect to my car now though so I can't blinking check it!

Not sure how an avcs fault is going to be worse when it's cold.

HI
I know yours is a 2002, i have a Classic 1994 Jap IOmport, From Cold mine is the same, As soon as its warm its fine.
I was going to take off the idle speed control valve tomorrow at work and clean it out to see if that changes it?
Also I have been told to clean the throttle body also.
Dont know if this is the correct things to do or not.

Could the plugs be a grade too cold for the level of tune ?

I had an Imp that was a bugger for sooting up the plugs in the first mile of use.

Random thought :-)

dunx

P.S. A faulty lambda sensor will get worse until it's very obviously "dead".

this can be agood start point on classic's mate,give the iscv agood soak to loosen all the carbon deposits though and use a little bit of wd40 after to keep lubed.

Cheers mate, Going to give it a go at work today, Will let you know what results I get
Cheers

Still searching for an answer to this.

I did some reading up on lambda faults yesterday and was hopeful it could be related as I actually found a specific post from someone saying they had rough idle and had to tickle car along when cold and it was lambda.

I don't get much chance to play with it but I fired car up yesterday and she starts perfectly, instantly, runs fine as I drive it out garage. By the time I've shut garage and gone back to car idle starts rocking and if I drive off before letting it warm a bit it's hard to accelerate. If you push the throttle harder it actually bogs worse like it's being held back and the revs don't climb. You have to just tickle it along.

I'm tempted to get a new front lambda sensor as I did get fault p1131 which was front o2 sensor voltage fault. Trouble is £100 odd and no guarantee it's going to be that.

have a very similiar problem with my blob sti but i have simtek fitted and thought this was the problem...the smell of fuel on heating up is really worrying to me also.its almost unbearable.
havent got equipment to interrogate the simtek ecu but was thinking of changing lambda probe!!
:wonder::wonder: