Rough start on 16v

[Ad2408 0]

Not a huge problem as it always (touches wood!) starts although when I first start it in the morning my 16v seems to run quite rough (like its firing on three-cylinders)

 

It sson calms down and then behaves fine for the rest of the day.

 

Any ideas?

 

I've tried to use the search but its difficult to find something when you don't know what your looking for!

 

Thanks

 

Adam

[Walesy 0]

Have you tried the blue temp sender mate?

[Ad2408 0]

Hadn't thought of that, I had to change that on my old 8v Golf, any chance its the same type or any chance of a part number?

 

Thanks for the help

 

Adam

[bcstudent 0]

Is this a 1.8 or 2.0?

[Ad2408 0]

Sorry..... Its a 1.8 16v 1991

 

Adam

[ben16v 0]

mine sometimes does this 1 in 10 cold starts, goes away after a little bit of rpm, not so much (once or twice) since i changed the leads a couple of weeks ago!

 

corradowales, how does a temp sender affect misfiring??

[alfarac 0]

Hey Guys, got a Stock G60, just bought it, and I'm having the same thing, only sometimes a bit worse... When I start it in the morning, and its not bad, it will be running a bit rough, after a min, then I just go, and its OK... but sometimes, I just start it, it'll misfire for about 5 to 10 secs, then off, start it again about 3 or 4 times, doing the same thing, then I have to give it gas until the car just behaves... I bought the sender, since I read that could help, but to be honest, don't know much since I just bought the car.. Any ideas??

 

Dont know if it helps, but the car, when I floor it smokes... but only when I step max on the gas, I know its running a bit rich, but again, just bought it.. Any help would be appreciated... thx!

[Walesy 0]

corradowales, how does a temp sender affect misfiring??

 

not sure mate..but i do know it made a hell of a difference when i changed mine....i think they're about £6-£7 and a 2 minute job so its worth trying it.

 

i think it might be that the engine is'nt being put into cold start mode....hence rough running when cold untill it warms up??? :? ..im sure someone will enlighten me.

[Phil.C 0]

Have you changed the spark plugs recently, they become 'lazy' after about 10k.

 

Phil C.

[Baz2004 0]

Have you tried cleaning out your ISV? I’ve mentioned this before and found it helped when I was having such trouble with my early valver.

 

New HT leads might help things also.

[corradophil 3]

Leaking injector dribbling petrol into one of the combustion chambers over night, which means it is flooded in one chamber in the morning or after being left for a long time.

 

Can't remember off the top of my head. Does this have a thermotime switch? Might be woth checking if it does.

 

Also I am guessing it has an accumulator which keeps the fuel pressurised whilst not running, so when you start it the pressure does not have to be built up by the fuel pump. Maybe this is playing up.

 

Try disconnecting the cold start injector's electrical connection, you might find this is flooding it at start up.

 

Hopefully all or some of the above appilies to the KR engined Corrado. The above things messed up the starting of My Mk1 GTI which had K-Jet.

[aide 0]

Phil, yep the 16v has a thermotime, but this only controls the cold start valve on start up, usually for 8 secs from below 35degs. If either fails it *can* make starting difficult, but as you note it *can* make mixture over rich too..

 

And yep, the fuel pump has a built in accumulator to maintain pressure, rest pressure can be tested, but you need the right brass fittings on pressure meter.

 

Ad2408 - getting a 16v to start/ idle can be a real pain, i'd start with the basics, plugs, leads, dizzy and then get onto the injectors, metering head, pressures, cold start valves, thermotime etc... if your a bit of a nerd like me then you can buy books explaining the entire KJet system :) dull but useful

[bcstudent 0]

My 1.8 16v is the opposite. It always starts fine from cold but if left for a couple of hours after reaching normal operating temperature it only starts with my foot on the throttle and then runs on two/three cylinders for about 10 or 20 seconds. I've gotten used to it now!

 

After a sustained period of driving above about 60mph it refuses to idle at under 1500rpm unless the engine is switched off and restarted too.

 

As I write this I'm wondering why I put up with the heap of junk. I'm off to buy a Ford.....j/k.

[-Neil- 0]

i brought this today. is it the right thing,

for a 2ltr 16v.

 

Plus mine doesn't like idling either!

It nearly stalled 2twice today after an hours or so driving.

[dinkus 10]

Looks like it's the right jobby to me...

[-Neil- 0]

and where does it go, i have no idea!

[aide 0]

Is it right thing for what?! Bit confused here

[davidwort 0]

My 1.8 16v is the opposite. It always starts fine from cold but if left for a couple of hours after reaching normal operating temperature it only starts with my foot on the throttle and then runs on two/three cylinders for about 10 or 20 seconds. I've gotten used to it now!

 

After a sustained period of driving above about 60mph it refuses to idle at under 1500rpm unless the engine is switched off and restarted too.

 

As I write this I'm wondering why I put up with the heap of junk. I'm off to buy a Ford.....j/k.

 

classic cold start valve problem, as mentioned above disconnect the cold start valve elec. connection and see if that helps on hot starts, the cold start valve is very crude and if the engine is stopped in a certain position all the extra fuel from the CSV gets sucked into one cylinder, this is part of the reason why cars can run poorly for the first few seconds on a cold start too.

Sounds like your ISV needs cleaning too.

 

David.

[-Neil- 0]

right can somone tell me where the ISV is and how to clean it and where to fit my new blue tmep sensor?

PLEASE HELP ME!

[-Neil- 0]

its ok just got a guide how to do the ISv, and found out my 2ltr 16v DOESNT have a Blue temp sensor!

[aide 0]

found out my 2ltr 16v DOESNT have a Blue temp sensor!

 

was a tad confused :wink:

[-Neil- 0]

i was told it was the blue temp seonsor, so went and brought one, but my engine dont have one,. going to try and clean the ISV, if i can!

[aide 0]

if it's the cold start valve your looking for it's got a similar blue connector on an angle from a cylindrical valve, and a connector for a fuel line, together with a connecting plate for fixing to the inlet manifold.

[Walesy 0]

what did you ask for then when they gave you that part mate???

 

and what is the part in the pic?

[Baz2004 0]

On the early 16V 1.8 KR there is an idle temp sender that goes into the side of the head beneath the water pipe, green and red wire comes out of it.

 

I had terrible trouble with idling until I found this switch was gone, my car would start from cold idle around 1200 then race to 2-3000 RPm the minute things would get a bit hot.

 

Since I’ve replaced this switch It hasn’t idle’d over 1100Rpm