16v trouble starting, misfire........................

[Diluxe]

my 16v seems to be getting worse, yesterday it took 4 attempts to start, and I had to have my foot to the floor to get it to catch.

this mornining when it finally did catch it misfired several times, before smoothing out.

get the odd misfire upuntil its warmed once that happens no problems, and it only happens in the morning.

I've read nearly all the posts, i dont really want to keep replacing parts.

So I cant see any perished pipes, should i buy the ecu temp sensor 1st or the relays or is it the lambda sensor ;-)

BTW no error on vag com

cheers

[Len]

ECU and Fuel injection relays first!

[Diluxe]

Ok to buy them straight from GSF? & if this doesnt work, I presume the ecu temp sensor is next?

[Len]

The reason I always say relays is because they dont show up on vagcom!
So therefore its logical that they will be the fault!

I am assuming you have checked the obvious things like plugs/leads/dizzy cap etc.


Any sensor be it temp or lambda should show up on vagcom.

[Diluxe]

Ah gotcha, yep checked the standard bits already.

I assumed that if the sensor was only giving sparadic readings then it woudl not appear on vagcom unless you managed to get a reading at the time it was going faulty , if that makes sense, or will the error be logged even if it works it self out?

[Len]

Error log should be retained.

[Mikester]

Does it ALWAYS not start first time. Every time, without doubt in the cold? If so how does it idle when it does start in the cold?

Or is it a bit random, and can start if it feels like it? If so i reckon it COULD be distributor related. Although ECU relay is also very likely as len said. Although the ECU relay would cause the car to randomly cut out as well as not start? Same as the fuel relay.

Needs to be a bit more specific with syptoms, as some things will just stop it from starting, where as others will cause bad running.

[Diluxe]

Yep definitely only happens on cold start and I mean morning start , as when I start it at after work it fires up luvely jubbly, but i still get the occassional hestitation/misfire but nothing as bad as in the mornings.

In the morning everyday this week so far its failed to catch unless foot is to the floor, then i need to keep my foot on the accelearator to keep the revs up as it kinda of looks like its going stall, this is only for maybe 10  secs, after which point i can leave it to idle, i can still hear it idleing roughly from the exhaust, although the rev counter is rock steady.

when i got moving the misfires/hesitations continue randomly until fully warm then everythings is fine, and the car feels normal & fast , I dont suffer from stalling at all.

 

[Mikester]

What rpm does it idle at when its cold?

As it should raise the idle itself to 1000rpm or just over when cold.

Then when warm it will drop the idle to about 900rpm.

[Diluxe]

I would say 1100rpm then dropping down to 900rpm , but this happens all in under 1.5-2 mins i would say , i guess it would take longer when its really cold.