8v bucking slightly on cold start

[davidwort 0]

Digifant 8v (2E engine), it runs smoothly, good power excellent cruising mpg, timing set correctly, recon head, new cat and lambda sensor, good plugs, new leads etc but one small annnoying trait.

When the car is cold (ambient temp under about 10 degrees), if you start and drive away immediately it's jerky on the throttle, give it 20 secs driving, or idle for 20 secs after starting and it's fine.

I've also checked and renewed earths, ignition coil to head etc, even checked the 4 pin water temp sensor is showing within-range resistance and swapped to a spare I have, problem still persists. cleaned throttle body, ISV etc.

It's not major, just annoying I can't get to the bottom of it. I'm currently thinking injector spray pattern/delivery as it's on 150K, any ideas anyone before I take the injectors off for refurb/replacement?

The only other possible culprit is the schrick cam it has in it, it's mild and doesn't really affect idle, but perhaps the standard map isn't suitable when the ambient temp is very cold?

[robrado974 1]

Every car is the same David , if I got in mine and drove it straight away it would be awfull . I always start mine , walk away and come back five minutes later , then drive it .

Rob

[delfinis38 1]

Every car is the same David , if I got in mine and drove it straight away it would be awfull . I always start mine , walk away and come back five minutes later , then drive it .

Rob

 

that sounds like your talking about my lawn mower :)

[James. 7]

Tend to think that if there was an issue with injector spray, then it wouldn't clear up after getting warm ? And you'd see a change in MPG.

 

Seems you've checked all the right things. Vac leak ? Swap the ISV with a known good one ?

 

Maybe live with it for a while and see if it gets worse/better. Be sure to let us know how it gets on.

[davidwort 0]

Cheers guys :)

I'm thinking injectors as from what I understand, poor atomisation is made worse by low ambient temps, just not familiar with the digifant injectors and don't want to make things worse, I suppose I could call an injector cleaner specialist and see if they do digi squirters

[davidwort 0]

Every car is the same David , if I got in mine and drove it straight away it would be awfull . I always start mine , walk away and come back five minutes later , then drive it .

Rob

 

Now every one with web access can find out you leave your car running unattended for 5 minutes every morning, hope it's still there tomorrow :lol:

[robrado974 1]

Lol , i like to leave it running so it warms up . With two dogs that go ballasitic if anyone comes within 20 yards of the house i think my car is pretty safe !