# cis basic fd -> volvo 240t fd



## jason08 (Dec 1, 2007)

I only recently realized that my car is actually cis basic, not lambda, it has no o2 sensor, and there is no frequency valve port on the stock fd... i installed a volvo 240t fd which Has a frequency valve etc, only i dont have the wiring or anything for it ...









http://****************.com/smile/emthdown.gif would it do any harm to just remove the fequency valve and plug the small port on the fd, and use the shorter bolt off my cis basic fd to get rid of the longer bolt which holds the frequency valve and fuel filter line?
Also, because im using the volvo 240t fd, the cold start line isnt long enough to reach the cold start injector on the tb, can that also just be blocked off temporarily till i can find a longer line?








Thanks,
-Jason 


_Modified by jason08 at 9:07 PM 7-1-2009_


----------



## Southcross (Jul 2, 2004)

*FV-QR*

what was your reasoning for installing a Turbo fuel dizzy?


----------



## Southcross (Jul 2, 2004)

*FV-QR*

ha... happened across this by accident researching something else...
http://store.autospeed.com/Ite...uster
this could theoretically be used to control the frequency valve, set it to 50% operation and forget it...


----------



## raaustinf16 (Jun 18, 2009)

*Re: FV-QR (Southcross)*

I have a similar problem. I do not have a Turbo Dizzy. Just one with a Freq valve. I have a basic system. What do we do with that port?


----------



## Southcross (Jul 2, 2004)

*FV-QR*

if someone ever figures it out... please make a DIY thread and post it up :t-up:


----------



## jason08 (Dec 1, 2007)

*Re: FV-QR (Southcross)*

I figure I'll just leave the frequency valve hooked up, i dont have the electronics to run it, so it wont function at all, but it'll atleast redirect the fuel back to the FD and i wont have to plug it, and i worry plugging it wouldn't be a good thing because its an exit port, where would the fuel go? would it pressurize if you plug it?
As for finding a longer cold start line, im thinking maybe i'll have to get a longer one made, maybe i should just even go with rubber fuel line, ive never attempted braided steel line


----------



## jason08 (Dec 1, 2007)

oh and , southcross, im using a volvo 240 turbo FD, because im going the forced induction route.


----------



## Southcross (Jul 2, 2004)

*FV-QR*

without the ECU to operate the FV (any FV), it will lack the ability to increase fuel flow (i.e. richen the mixture). without that ability, you won't gain any benefit to having the 240 dizzy... your basically just running a fancy "basic" distributor.


----------



## jason08 (Dec 1, 2007)

*Re: FV-QR (Southcross)*

thanks for the reply, so basically... im better off just putting my old cis unit back in? Should i still run my audi 5k turbo WUR with it?
I'm using a relatively small turbo (td04hl-15g) off a volvo 850, so its going to be low boost hoping for 10psi on my 1.7 8v... 
I guess another option would be finding a lambda O2 brain and wiring right? I have a bentley manual so wiring shouldnt be too difficult ?


----------



## jason08 (Dec 1, 2007)

anyone? Theres a bunch of mk1's at the junkyard , im sure one of them will atleast be lambda, is it possible to add the lambda harness to my basic cis so i can utilize the frequency valve, o2 sensor, etc.....?


----------



## Southcross (Jul 2, 2004)

*FV-QR*

grab the entire harness and ECU from a 83 or 84 model that has a full throttle switch (including the throttle switch, you might need the whole throttlebody)... other options are an early Mk2 that uses a FV (might require harness modification/rewire)... or, find yourself an early Audi5000 turbo and get everything (harness, ecu, throttle, warm up regulator, etc)


----------



## jason08 (Dec 1, 2007)

*Re: FV-QR (Southcross)*

Picked up a the wiring harness, WOT switch, and jetronic module, let the wiring begin








Thanks for all the help, I'll post any progress or problems if i run into any (hopefully not)








-Jason


----------



## jason08 (Dec 1, 2007)

*Re: FV-QR (jason08)*

off to a bad start







WOT switch = fail Thermal time switch = fail... i need the TB from the cabrio, and the coolant flange that has both holes for thermal time switch and coolant temp. sensor... didnt even think about that http://****************.com/smile/emthdown.gif 
*sigh* this is going to get expensive... Will the jetronic module function properly without a TTS and WOT switch? -__-


----------



## Southcross (Jul 2, 2004)

*FV-QR*

you just need to be creative until you have all the components... by shunting the coolant temp switch leads the ECU will run in warm-up mode. The WOT switch just leave it disconnected until you get the TB. One thing you could need also is an O2 sensor (if your car doesn't already have one). If the ECU is in "perma-warmup" mode it ignores the O2 sensor (if you don't have one). 
The only headache ahead may be "tuning" your mixture, especially if you don't have an O2.


----------



## jason08 (Dec 1, 2007)

thanks again for the help, much appreciated!


----------



## jason08 (Dec 1, 2007)

*Re: (jason08)*

Sorted a few things out, used my spare audi 5000 wur line as a cold start line because its alot longer, had to bend the end a little to fit properly on the FD, sorted out the mess of wiring for the jetronic ecu, i just need a relay i forgot at the wrecker...


----------



## antichristonwheels (Jun 14, 2001)

*Re: FV-QR (Southcross)*

The matching WUR from the Volvo is what senses boost and gives you more fuel. Lambda is for emissions control.


----------



## jason08 (Dec 1, 2007)

*Re: FV-QR (antichristonwheels)*

-__- i wondered about that, I was reading more about the turbo WUR and how it acts more like a fuel pressure regulator, sensing boost and adjusting fuel flow accordingly... so on the opposing side, a frequency valve just works along side an oxygen sensor and the jetronic module determines the correct fuel mixture? 
I guess my real question is, by not running a frequency valve, but still having it attached, will there be any restriction to the flow of fuel? If i wanted, could i remove it completely, and just have a single fuel line connecting the two ports?


----------



## antichristonwheels (Jun 14, 2001)

*Re: FV-QR (jason08)*

plug the 2 ports, do not connect them with an open line.


----------



## jason08 (Dec 1, 2007)

I plugged the small port, the larger port I used a shorter screw from my old FD unit because it holds both frequency valve line and line in after the fuel filter, so now i just have the fuel filter line hooked up.
Thanks for the help


----------



## jason08 (Dec 1, 2007)

*Re: (jason08)*

So I ran into a problem... As stated before I plugged the frequency valve port on the volvo 240T FD, and removed the longer banjo fuel screw and used my stock short screw that holds 1 banjo where the fuel line connects to the FD after the fuel filter... Well... I turned the key, the pump turned on, but then it slooowly died down, I turned the ignition off and looked under the hood... there was fuel slowly running from the plugged frequency valve port...








Is there any way I can bypass the #$^&'n frequency valve on a volvo 240T FD used on a CIS basic car??







or should I go back to my stock FD? which I worry will run too lean... can I use an Audi 5K WUR along with my stock FD to help?
Any help would be appreciated , Thanks!


_Modified by jason08 at 11:42 PM 7-9-2009_


----------



## Southcross (Jul 2, 2004)

*Re: (jason08)*


__
Image uploading. Refresh page to view


----------



## ellocolindo (Jan 15, 2010)

so there is no way to leave the Fv line attache din there?


----------



## gamblinfool (Sep 28, 2001)

jason08 said:


> I plugged the small port, the larger port I used a shorter screw from my old FD unit because it holds both frequency valve line and line in after the fuel filter, so now i just have the fuel filter line hooked up.
> Thanks for the help


I just did ^this^ - primarily because I didn't have any other options for FD and I needed to swap a different unit in there to test. After leaning it out considerably, I got it to run. Then I took it to my mechanic who has a gas analyzer to dial in the mixture. While we got it close, it's still a little on the rich side and stumbles under load - both light and full load; though it's considerably more prevalent when cold and/or under light->med throttle.

I'm beginning to suspect my WUR and will try swapping out others unit to test the stumble.

This is on an N/A application BTW (Eurospec 8v head / ABA bottom / CIS Basic+K/S)

On a related note, does anyone know what the longest VW/Audi OEM CIS braided injector line is? The #1 cylinder only barely makes it to the Volvo port and that's having to run it over the intake boot and valve cover. Even then, it's got too much tension for my liking...


----------



## ellocolindo (Jan 15, 2010)

i pulled a motornic FD from a 91 passat i sold today and i got thinking maybe the passat lines can be used for other carS?
or the pitch and thread on the injectors are different from motronic to older more basic CIS?


----------

