cold start problem
 

In the last 2 days i have got a surge between 1500 and 2000rpm .

Normally on a cold start my car revs to 2100 rpm then slowly settles down to 1500 , then to 1200 then down to 900 rpm with no problems . ;)

The last 2 mornings i am seeing a swing between 2100rpm down to 1500 rpm then back up to 2100 rpm :eek: it does this several times and then finally settles down .

Theres no rough idling once i take off and car drives smoothly :cool:

Any one experience this ?? i have done 42,000km .

Maybe i need new spark plugs ??
bad cat sensor
Bad ignition coils
loose wiring

Any thoughts .

B....free
michael

I normally get one little surge like this on every start (see graph here https://www.rx8club.com/showpost.php...6&postcount=22).

Seems to be the same problem on my car however it goes up and down between 2100RPM AND 1500RPM at leat 9 times before settling .

could it be a blocked fuel line / injector that clears after a certain time ??

B....free
michael

I get this, normally in the afternoon not the morning. But Lock, didnt you just install the pipercross filter?

Andrew

No i still have the stock filter in .

B...free
michael

I only get the initial surge you mentioned Lock.

i think it's normal, sometimes i get 1 surge and sometimes 2, no big deal. i think it just depends how the cold temperture is.

Actually, now that I think about it, I'm pretty happy to be getting any surges in the mornings!! :p :D :D :D

I think this could be it because if i put in reverse straight away it does not cause the rolling idle :cool:

Now how do i fix this ???

Worshop manual says for a slow return to idle check following .

.ECT sensor malfunction
The thermostat is stuck open
throttle body malfunction
Air leakage from intake air system .
Eccentric shaft bypass valve stuck open

However i feel youhave found the correct answer to my problem .

B...free
michael

"Cold start" in Surfers Paradise...ho ho

It was -11 in Walcha thismorning Lock, but they say the cold weather is coming in the next day or two!
Have enjoyed the discussion in your Duck thread very much.
jack

:eek: i get cold when it drops to 15 , thats one of the reasons i left melbourne its wet and freezing .

Going overseas to the PHILLIPINES for the month of September partly bussiness but mostly R&R THE TEMPERATURE THERE WILL BE 29 /30 :)
The scuba diving on the island of MINDORO ,sabang beach puerto gallero , and i here the women are as hot as the weather :D

Glad you enjoyed my Duck thread its hard to get some of these guys to comment on controversial matters , so i was quite suprised that some actually came out and responded .

Hoping you and family are all well , are you coming to wakefield in october ??

B...free
michael

Unfortunately not doing Wakefield, Lock. Initially thought it was the long w'end, when half our friends from Sydney want to come to "spring in Walcha". Timbo corrected me, however the Nats weekend is the Forster-Tuncurry Golden Oldies rugby carnival, an event I have not missed in over a decade.
Might this be the year to break the mould?

You bet... We'll pick you up on the way through.. :D Are you closer to Brisbane or Sydney?

I get a surge like you're describing pretty much every cold morning........ it's normally 6-8 degrees ambient when I fire it up in the morning.

Myself and the Hymster meet up with Jack and his lovely wife last time , we went to Wakefield it was :cool:

B...free
michael

We rendezvoused with Jax and Mrs Jax just north of Newcastle. Closer to Sydney than Brisbane.

If Mr Jax can't make it, then perhaps Mrs. Jax can have the car for the weekend and join us at Wakefield? :) It's only football after all.. :D

Ditto on the cold weather.......bollocks

Yep get the old cold morning jiggle occasionally to. Especially if I roll backward on idle while it's warming, driveway has a slope and I swing around. Tend to get a small double surge.

So what was the conclusion with this?

I get what I believe you are getting but only in the afternoons. I cant believe its the temp as its generaly about 5-10 degrees warmer in the arvo atm.

I have some Video showing this but cant get it up until tomorrow.

Andrew

I think he is going to put a heater in the garage before he starts his car ;) :D

The gear selector seems to be stuck upon cold starts causing this problem so
Keeping your foot on the clucth on cold starts wont give the rolling surge , as the gear selector is disengaged .

As to a more permenant fix i am still waiting for an answer .



B....free

Michael

Hmmm.. Not sure what gear selector stuck really means.. Is the spigot bearing dry when it is cold and this is still turning the main shaft of the gear box??? :confused:

Surely, the drag on the main shaft of the gearbox of a car in neutral would not cause this??? :confused:

Very strange, but is it really a problem??? Are we worried that in the longer term that it will lead to a stall on cold start problem?? :eek:

This makes no sense :confused: Do you mean you cannot budge the gearstick, which has been left in gear, so that when starting the car you have to press the clutch? (In which case, you need to have your gearbox examined) Gear position or selection should not affect the cold start program, although whether the clutch is engaged or not may, as it will be a load factor taken into account by the program.

More importantly, I have more, colder cold starts...and I don't have this surging problem. Just the initial high idle, as previously discussed.

OK lets be more precise i am led to believe that the "in gear "or neutral switch is sticking ....causing this rolling idle situation on cold starts .

B...free
michael

OK I want to check that this is the same problem.

htp://rx-8.harrisfamily.id.au/ColdStart.wmv (8Mb)

First part is the morning. Ambient Temp was 10 deg, I got in the car, didnt clutch, didnt move gearstick.

Second is at 7pm at night and amb read 17 deg. This time, before I started, I clutch, checked it was in Nuetral by moving gearstick left->right.

Sorry for the quality.

Personally I dont think this is a problem, its just bizzare. The first time I though something was wrong, but it happens so often its obviously something the car just does. I am just curious what it is.

Andrew