Stevesbluewrx

iTrader: (4)

Looking for some advice as I can't work out what the hell is going on with my car at present?

Recently the weather temps have dropped and all of a sudden I am suffering from bizarre startups. Noticed it when leaving Goodwood the other week following driving in the horrible rain there a few Sundays back.

On start up from stone cold the rev's only go up to around 1,400 rpm and doing so causing the car to hunt slightly (almost misfire) then stops.....( whilst running rich as hell)........whilst still on cold choke the car finds the idle speed of 950/970 rpm but soon as you engage gear to pull off the revs drop to around 550 rpm almost stalling and the ECU catching it.

If you give it a little right foot you can hear that it's almost wanting to misfire ( between 1,250 - 1,450 rpm ) but beyond that not a problem.

Once up to speed and fully warmed up it runs fine yet still running richer than I think it should.

Car in the past has had fuelling issues with lines popping off (my fault for not getting billet rails) causing poor starting.

I check the lines very regular and on this occasion was the first thing I checked. ALL seem fine and not getting any signs of fuel leaking (smell) and I am not getting through anymore fuel than I would normally.

FPR reading on idle (warm) 3.5 bar.

I'm using grade 7 plugs that have been in now for around 800/1000 miles . Same as what the car is mapped on.

I've checked all FMIC clamps, and intake clamps and all are fine all be it a few needed some minor turns on the ratchet.

I noticed last weekend that an earth cable has come adrift from the manifold (god knows how or how long for?) but have re-bolted it back on and checked all other earths in the engine bay and are fine.

I'm due an oil change very soon but has used no oil or coolant.

Had similar thing last year which ended up being a number of things including Fuel Leak, Split DV delete pipe and finding out my cambelt was a tooth out.

Vital info for assistance. I have the following.

SimTek ECU
850cc injectors
FPR
FMIC
CAIK
Coolant T/Body delete


I'm a little unsure as to what it can be? I'm going to throw a few ideas into the ring and await a response from the wise men of SN.

Coil Pack (s)?
Rear Lambda failing /failed ?
Bad Batch of fuel ?
New Spark Plugs needed?
Cold Start map check required?
ICV needs cleaning (AGAIN).
NPS


If anyone can shed any light that would be great.


Cheers
Steve

d4vidh

Are you running MAF less?

barnshaw

iTrader: (1)

possibly your coolant temp sensor?

Andy Stevens

If it is an alcatek that hasn't been updated it won't have closed loop idle control. As ambient conditions change the ECU won't react to stabilise the idle. You can get the ECU updated to rectify this.

Stevesbluewrx

iTrader: (4)

Cheers for the reply folks.



Yes matey.

Hmmm? Would that cause those symtoms then? Not really thought about that.

I am waiting for the all clear when I can get my ECU out and sent off for the update. Trouble I have is the car is used daily so needs to be really when I am off etc .

I know and understand problems with the cold start issues on the SimTek.

Just weird how all of a sudden the colder weather starts and it plays up?



Cheers
Steve

JDM_Stig

iTrader: (3)

I agree

merlin24

iTrader: (1)

As above, coolant temp sensor would be my first thing to check as it will give the above symptoms if its on its way out.
Also the coolant delete on the T/B wont help the drivability through the winter months.

Mick

Stevesbluewrx

iTrader: (4)

Cheers guys. I'm waiting for my new sensor to arrive.

I'm still using the car and have no choice but to use it.

It's getting worse too if you ask me.

How likely is it I'll loose coolant on install of new sensor?

Once installed anything I need to do to assist it learning on the simtek?

I'm just hoping its not signs of head gasket?

RICHARD J

iTrader: (4)

My Simtec behaves exactly like this all winter & is worse the colder it gets. It's fine in the summer & Iv just got used to it as it runs great when warm. Once the initial rush is over I'm going to get the Alcatec update & a remap which should fix it.

Stevesbluewrx

iTrader: (4)

Sensor has arrived, just not had the chance to fit it yet. When I did have a chance my kids decide to get ill meaning I can't leave them or bring them outside with me.

Hope to get it installed tomorrow and hopefully this will cure the issue?

Steve

Stevesbluewrx

iTrader: (4)

I've had this too. Seems a common issue.

Again liek you just waiting for the ECU to go off for a upgrade and check.

Steve

L.J.F

iTrader: (31)

You will only lose a bit of coolant and nothing to really worry about, just try to get the new sensor in place straight away and you will be ok.


Have you already changed the 02 sensor?

Stevesbluewrx

iTrader: (4)

Hello mate yes but the Front o2.

From my understanding now though I think it is the rear the Simtek reads signals from but not 100% sure.

Steve

Stevesbluewrx

iTrader: (4)

Well, sensor changed. Tested an only a slight improvement.

Just prior to the sensor change had to get the car out the garage......kept idle until all of a sudden it dropped way to quick on cold idle down to 450rpm.....and had to be caught by the ECU and a little right boot.

Really annoying. Don't know if it's worth treat the ICV again or not? It's only 2 years old?

Steve

Turbotits

iTrader: (2)

Yep simtek only uses rear sensor on a new age. Its needs a little tinker from your mapper. Mine did this when it was first installed as the mapper didnt see the car cold. So everything the car does cold is guess work. My mapper came to my house. hooked his gear up and adjusted the cold start stuff with a cold engine. Its been perfect ever since

Stevesbluewrx

iTrader: (4)

I thought so squire. Not sure if to buy a replacement rear lambda or not?

Been asking for a cold start check for ages now (almost 2 years lol) but the fella is too busy.

Stevesbluewrx

iTrader: (4)

And the wait continues........

Sounds like a wrc escort cosworth now.

Always wanted one of those.

LOL