Frustrated with CIS

[Dsp99t]

CIS is a bear if you dont follow the proper procedure to diagnose and set everything. You have to systematically check everything. I think I know my way around a Saab pretty well, and I take it to a Saab mechanic when I have CIS issues.

On that note:
FOR SALE
One CIS injection system with two computers

I'm going megasquirt.

[SwedeSport]

In all your fiddling with it, is it possible you cracked one of the injector lines? Check to see if you can see solid fuel flow through them. If you see air bubbles in the lines it could be from a crack. Its easy to do when you are leaning over the motor.

Do you have a local Saab independent mechanic? Before you give up, maybe find out how much he wants to troubleshhot your system.

Most of the diagnostic stuff can be done with a multimeter. But you need a special Fuel pressure gauge for CIS.

It frustrates me too, so I take it to a Saab shop for CIS tuning. I have owned the car for about 12-13 years. Truthfully it has been very troublefree considering. If I break down the FI maintenance and repair costs over the time I have driven it and owned it,... I would say it has cost me 5-6 bucks a month over my tenure as its caretaker.

[SwedeSport]

I think there is a guy near you that works on Saabs.

Tim Nine

Not sure if he still works on them for a living, but he tinkers with Saabs. He builds custom trikes. Some with Saab power.

He has a website for the trike thing. Ill see if I can find it for you when Im not posting from a phone.

[Dsp99t]

I think the biggest problem with mine is the previous owner who gave up on it the moment it hiccuped. I don't see any bubbles in the lines but it isn't lean any more its pig rich. The frequency valve doesn't make a detectable sound but the fuel lines get cold, so there is flow.

In Charlotte there is no saab shop that I can find and the euro specific shops hang up when I mention CIS



I do have a complete megasquirt with harness on the shelf waiting to go on.

[DeLorean]

Ok, well you know... if you can't get the k jet working, megasquirt might be tricky too however if you have a defective warm up regulator... well a new bosch unit probably does cost about as much as a megasquirt control unit, so kind of a no brainer. I have megasquirt on my 88 spg, and it has been very reliable over the years.

[Dsp99t]

My good friend came by and we ran some more diagnostics. Two things became clear one no pulse signal is reaching the frequency valve and the existing valve is stuck open. I have a spare valve that clicks when energized.

[Dsp99t]

Question on relays. Is the lambda relay the one screwed to the bottom of the fuse panel?

[Crazyswede]

Question on relays. Is the lambda relay the one screwed to the bottom of the fuse panel?

Lamda = frequency valve. Not sure exactly where the relay is.

[Dsp99t]

Ok I've found the problem but I'm not 100% sure how to solve it.

Both the frequency valve and computer are not getting power 12v+ when I run a wire from the battery to both it all starts working. So my guess is a relay is not doing its job. I'm guessing its the fuel pump/fi relay. The issue is where can I get a replacement? My parts house gives me dumb looks when I ask.

[Jordan]

do you have a photo of the relay? I have bag full of CIS stuff I saved when I converted to carbs... although nothing was plugged in or was relayed in my car , which ran surprisingly well.

[Dsp99t]

I am assuming this is the curit since it looks like its been apart a time or two.

[Jordan]

I wont be home until thursday but I can check for you. A pic of the bottom might help figure out how it works. Is there a diagram on it as well?

[Dsp99t]

Turns out this one is fine. The rest are normal single or double pole relays so I'm actually ok I think.

[Dsp99t]

I should probably get a replacement for that one anyway

[99Super]

I just run a standard 99 Lambda fuel pump relay. The 99T relay is the same as a normal 99 fuel pump relay except that the extra width and pin are used as a rev limiter fuel pump cutoff.
Get or build a CIS inspection harness. You [i]cannot[i] diagnose CIS without it. It's a gauge and valve in a line that replaces the line from the fuel distributor to the warm up regulator. That and an old-school dwell/tach gauge will diagnose nearly everything on a CIS system.

Or MegaSquirt it.