Anybody GOod w/ CIS injection on an '87 Cabriolet?

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
And yes, it was an aluminum head and it was already helicoiled :(. Luckily, a used head is nice and cheap (1987 Volkswagen Cabriolet 1.8L 8 valve). But, I came up with a temp solution (which is sorta holding), JB weld. Yes, JB welding a helicoil insert (one of the cheap ones from Autozone) and putting the spark plug into the helicoil. It works.. for now.

On another note, is anyone good w/ CIS fuel injection from Bosch? I am having a helluva time with the starting aspect. To get the car started, it has to be floored, and to idle you have to rev it up to ~4k rpms at least 7 or 8 times. Then it idles. Any clues?

Cliffs:
1. JBWELDFTW
2. CIS fuel injection?


EDIT: Title changed to reflect current Issue
 

exdeath

Lifer
Jan 29, 2004
13,679
10
81
Wow, duck for cover when that thing is revving lol. Toastedlightly --*headshot*--> exdeath with <sparkplug>

No on the CIS, but I'm reading about it now. Looks interesting.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
:laugh:

Good luck with the JB Weld. There are better alternatives, but unless the stuff was applied perfectly, it won't hold against that type of abuse.

You could have the hole drilled and tapped for an 18mm plug or something, but obviously you would have to remove the head anyway.

As far as the starting problem, something is wrong with the cold start injector or whatever method it uses to richen the mixture for starting.
 

natto fire

Diamond Member
Jan 4, 2000
7,117
10
76
Originally posted by: Eli
:laugh:

Good luck with the JB Weld. There are better alternatives, but unless the stuff was applied perfectly, it won't hold against that type of abuse.

You could have the hole drilled and tapped for an 18mm plug or something, but obviously you would have to remove the head anyway.

As far as the starting problem, something is wrong with the cold start injector or whatever method it uses to richen the mixture for starting.

CIS is quite a different beast from most other fuel injection systems. It really resembles common rail diesel injection more than more typical fuel injection systems. It is more of a mechanical system than anything else.

OP: You might want to make sure your air float valve is moving freely. A stuck valve might cause the symptoms you describe. I am no expert on K Jetronic systems, but this would be the first place I would look.

It's simplicity makes diagnosing problems a bit easier, but the causes of those problems can be a bit tricky. If you have a way to check fuel pressure, ensure that it is at optimal levels as well.
 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
Well guys, the JB held for a day. Plug shot out :p. Currently tapping it to an 18mm plug (shorter depth.. so I lose any performance) but oh well. All i need is to run and drive. I do have another I dea about fuel pressure though. Would the pump not building up pressure cause this at all?

Also, where is the air float?
 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
Update again:

Spark plug hole tapped out to 18mm (was 14mm), larger plug used, problem solved. Anybody have any other ideas on the CIS injection?
 

slag

Lifer
Dec 14, 2000
10,473
81
101
did you tap it out with the head on the car? Did you have positive pressure flowing through your intake valve or something to keep the shavings out?

or did you pull the head and do it..
 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
<div class="FTQUOTE"><begin quote>Originally posted by: slag
did you tap it out with the head on the car? Did you have positive pressure flowing through your intake valve or something to keep the shavings out?

or did you pull the head and do it..</end quote></div>

Well, my dad took care of it. He said he was going to have the engine on the intake stroke so he could blow air through the throttle body and force the shaving out. Combine that w/ a greased tap and a shopvac w/ a custom end for getting metal shavings, I think we're set. Also, the aluminum is softer than the steel, so if any was left (which I doubt), it won't cause /too/ much harm.

Head kit is 70 bucks.. screw that :p. I paid 400 for the car (+100 dollars in parts to get it to this point of running). I am set for a year.
 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
Originally posted by: exdeath
Wow, duck for cover when that thing is revving lol. Toastedlightly --*headshot*--> exdeath with <sparkplug>

No on the CIS, but I'm reading about it now. Looks interesting.

Yea, the plug came out as I avoided death. I merged over with a car ~500 feet back. I check again as I am merging and BAM, theres a car barreling down on me. My response was to floor it. POP! Spark plug shoots out, the force of it coming out and swinging on the spark plug cable closed the gap on the plug. I drove it home on 3 cylinders (kept up w/ 45 mph just fine). Rugged little bitch she is.
 

Colt45

Lifer
Apr 18, 2001
19,720
1
0
I've got a few cars with CIS. it kinda sucks, but it's better than a carb.

rule #1 - no vacuum leaks. look everywhere. any leak between the metering unit and the engine will cause problems.

Provided there's no vacuum leaks, look into the warm up regulator and cold start valve. check the mixture. etc.



in the old vags, cold start valve runs off a thermo time switch. switch will be on for say 10s if its very cold, and less for warmer (ambient) temps.
 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
Originally posted by: Colt45
I've got a few cars with CIS. it kinda sucks, but it's better than a carb.

rule #1 - no vacuum leaks. look everywhere. any leak between the metering unit and the engine will cause problems.

Provided there's no vacuum leaks, look into the warm up regulator and cold start valve. check the mixture. etc.



in the old vags, cold start valve runs off a thermo time switch. switch will be on for say 10s if its very cold, and less for warmer (ambient) temps.

Yea, I am picking up carb cleaner or starting fluid and am going to go over the engine. The lines that go into the fender though throw me off (I think they are vacuum) and reappear somewhere else. I do think it is a vacuum leak, I just have to find it. (stumbly idle, but runs just fine at any throttle). Also, could the idle mixture be off? Ther is evidence it was messed with (screw head is stripped)
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
You've got more balls than I, drilling and tapping a spark plug hole with the head still on the engine. :Q

Your precautions sound good, but damn.. LOL.
 

Cdubneeddeal

Diamond Member
Oct 22, 2003
7,473
3
81
I think you're problem, as stated, is your thermotime switch, CSV, or the wiring going to it. How does it start up when the engine is warm? Also, the idling issue maybe your throttle/idle switch is faulty. Grab a Bentley to do the appropriate checks. If those check out okay, then move on to the mixture. With my 88 GLI, with good idle/throttle switches, and running rich, the engine would lope at times, especially when cold. Have it bouncing of 5ma per the Bentley now all is fine.