CIS cold start injector questions

641 Views 11 Replies 5 Participants Last post by lyledriver, Nov 27, 2001

lyledriver

Discussion Starter · Nov 27, 2001

Mornin,
You may have noticed that most of my questions these days are regarding "winter related" issues.. well keeping with the trend..
Could someone please explain to me exactly how the CIS cold start injector works..

What I know:
Its a 5th injector.
It injects fuel while the engine is cold
There may be a relay for it?
What I dont know:
What triggers it
What the voltages triggering it are
Where this possible relay is located on an 85 Jetta
How to test it..
everything else
Vdubs/Broke I'm looking in your direction

Thanks guys

See less See more

Save

1 - 12 of 12 Posts

Espen W

· #2 · Nov 27, 2001

Re: CIS cold start injector questions (lyledriver)

It is triggered by the thermo time switch on top of the water pipe. Temperature of coolant will determine how long it will spray. Test by disconnecting it and crank the engine. Spray into a plastic bag or sumthin. Do yourself a favor and get the Bentley for exact procedure and voltages.

Save

lyledriver

Discussion Starter · #3 · Nov 27, 2001

Re: CIS cold start injector questions (Espen W)

quote:[HR][/HR]Do yourself a favor and get the Bentley for exact procedure and voltages.[HR][/HR]

hrmm.. yeah, I have a haynes.. and it just doesn't cut it..
I think I'll be asking for one for xmas

See less See more

Save

Vdubs

· #4 · Nov 27, 2001

Re: CIS cold start injector questions (lyledriver)

quote:[HR][/HR]
What I know:
Its a 5th injector.
It injects fuel while the engine is cold
There may be a relay for it?
What I dont know:
What triggers it
What the voltages triggering it are
Where this possible relay is located on an 85 Jetta
How to test it..
everything else[HR][/HR]

A 12 volt feed from the starter curcuit goes to the injector and the ground on the injector is switched through the thermotime switch. It will only spray for a few seconds, the colder the engine the longer it sprays. Test as previously described.

See less See more

Save

Blitz16v

· #5 · Nov 27, 2001

Re: CIS cold start injector questions (Vdubs)

it is on cis-e as well, cold start enrichment... so it is a totally separate injector? I was under the impression it was just feeding the injectors more fuel for an additional 30-60 seconds[16v cis-e], and decreases as needed..

See less See more

Save

lyledriver

Discussion Starter · #6 · Nov 27, 2001

Re: CIS cold start injector questions (Vdubs)

Vdubs,
Thanks for the info so far..
Could you explain the operation of this "thermotime" switch and its location?
(ie. temperature ranges etc)

Save

Vdubs

· #7 · Nov 27, 2001

Re: CIS cold start injector questions (Blitz16v)

quote:[HR][/HR]so it is a totally separate injector? I was under the impression it was just feeding the injectors more fuel for an additional 30-60 seconds[16v cis-e], and decreases as needed..

[HR][/HR]

Yes, totally separate, about 15 seconds is the max length of time.

See less See more

Save

Tornado Wolfie

· #8 · Nov 27, 2001

Re: CIS cold start injector questions (Blitz16v)

quote:[HR][/HR]it is on cis-e as well, cold start enrichment... so it is a totally separate injector? I was under the impression it was just feeding the injectors more fuel for an additional 30-60 seconds[16v cis-e], and decreases as needed..

[HR][/HR]

there's a totally seperate injector. On my 8v it's on the right side of the intake manifold pointing towards ya at an angle.

See less See more

Save

Blitz16v

· #9 · Nov 27, 2001

Re: CIS cold start injector questions (Tornado Wolfie)

Hmm any idea where it is on the 1.8l 16v's I am interested, maybe ill just go check

See less See more

Save

Vdubs

· #10 · Nov 27, 2001

Re: CIS cold start injector questions (lyledriver)

It's in the top hose housing, it has a brown plug.
It's a switch that is operated by a bimetalic strip, the strip inside has an electric heater worked of the 12 volt feed (the ground wire from the injector), as you crank the eng the strip heats and bends the bimetalic strip which opens/cuts the curcuit grounding the cold start injector. The strip gets heated by the engine aswell so when you crank hot there's no ground for the injector through the termal switch.

Save

Vdubs

· #11 · Nov 27, 2001

Re: CIS cold start injector questions (Blitz16v)

On the same side as the dizzy in the inlet manifold at the front. Its got a blue plug and a fuel line going to it and it's held on by 2 x 5mm allen bolts.

Save

lyledriver

Discussion Starter · #12 · Nov 27, 2001

Re: CIS cold start injector questions (Vdubs)

thanx Vdubs

See less See more

Save

1 - 12 of 12 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.

Top Contributors this Month