hupp

Brad,

This is starting to feel like we're getting too complicated. It would seem unlikely for the connector to suddenly fail.

One potential failure point would be the tight bend in the wiring just upstream of the connector. If I remember correctly this part of the loom has to bend about 180deg to plug onto the switch and heat may have damaged/brittled the insulation in that bend.

If it were me, I would replace the time switch and cold start valve and see what happens. BUT, I'm impatient and compulsive and don't always make the best decisions.

checkmate1996

Optimator,

You are correct. I just realized what the problem was. I was trying to check for continuity on the connectors. When I realized there wasn't continuity, I figured I had a break in the wire. After digging a little more, I realized that several of the connectors have ONE yellow wire feeding to them and a BROWN/YELLOW wire that connects between the TWO CONNECTORS. So a continuity test won't reveal ANYTHING except No Continuity which makes sense.

So I am definately going down the wrong rabbit hole here. Uggh. I will verify the 12v is feeding the lines and then I'm done with this one.

Next step: Hook up the coldstart to the fuel lines and 'jump' the cold start to get verify I am getting a spray pattern.

Phew! I see daylight again!

checkmate1996

Ok: Here's the latest updates:

Cold Start Valve:
- Pulled the fuel relay
- Made an 8ft jumper on/off switch with 15A fuse (This way I could turn the fuel pump on and off from the engine compartment and not keep running to the fuel panel to stop the fuel pump. Worked like a champ!!)
- Disconnected the CS Valve from the spider
- Disconnected the electrical connector from CSV
- Turned on the fuel pump for about 1-2 seconds to pressurize system.
- Connected one lead on the CSV to ground.
- Connected other lead to Ignition +
- Result: The CSV sprayed 'picture perfect' as described in the Bosch manual and no leakage. I retried a second time and same result. So I feel confident the CSV is NOT the problem.

Thermotine Switch:
I went back and revisited the Thermotine switch.
Voltage:
First, I verified the connector was getting power with a low-voltage test light. (turned on ignition and plugged test light in connector and it ("there was light!")
Resistance(OHMS)
Then I went back with my digital voltmeter to measure the resistance again and compare based on what WSM recommended specs were.The WSM said at below 86F, the switch should measure the following resistance in OHMS.

Results:
- W & G Connected together- (WSM=20-40 OHMS (Mine = 37)) (In-Spec)
- W to Ground - (WSM=0 OHMS (Mine = 28)) (Out of Spec)
- G to Ground - (WSM=0 OHMS (Mine = 7.7)) (Out of Spec)

Given this information, I'm presuming the switch is bad and should be replaced.

New thoughts??

jpitman2

Here's a quote from Wally P on thermotime switches:
"
The thermotime switch for the cold start valve has a brown/yellow wire attached to "G" and two yellow wires attached to "W". If the switch is shorted, it will activate the cold start valve, resulting in a very rich mixture, killing a warm engine.
Measuring from the terminals to ground, below 86 deg F there should be 0 Ohms; above 104 deg F there should be 100-160 Ohms.
Measuring between the terminals, below 86 deg F there should be 25-40 Ohms; above 104 deg F there should be 50-80 Ohms."
I believe thermotimes are marked for no of seconds they conduct when energized and cut off temp - eg"8/30" meaning 8 seconds, cut off at 30C (85F) - meaning any thermotime with same markings should do the job. or something like that - see whats on yours?
jp 83 Euro S AT 50k

Dennis Wilson

The heating element in the switch has burnt and shorted to the bimetal strip. As a result the cold start injector is constantly powered. Replace it.

Dennis

hupp

Replace it.

checkmate1996

Thanks Dennis, Optimator, Hupp, and Jpitman!

New switch ordered...I'll post more results as I get that installled and tested!

928BC

I can't see how a shorted thermotime sw. is going to cause a hard to start when cold problem?

Dennis Wilson

Robbie,

You are right in that the CSV malfunctioning in this way will not cause a cold start problem if everything else is correct. Very often when the CSV is constantly running, the AF mixture is adjusted to compensate for the constant rich running and that is what causes the hard cold start.

Dennis

928BC

O.K. I get it, when the engine temp is cold you aren't getting the fuel augmentation from the csv on start because it now has been adjusted in to the fuel map(beacuse it is always running) with the a/f mix screw. I'm glad to see you back on the board Dennis!

Dennis Wilson

Robbie,

Not really back on board. Just helping (I hope) on threads I was previously subscribed Still working 6 days a week. Give it a few more months.

Dennis

jpitman2

Or it could be that thermotime is open circuit and no volts get to cold start injector, makeing starting difficult.......
jp 83 Euro S AT 50k

Optimator

That's what I'm guessing. Particularly, if the car started OK before when cold, and nobody adjusted the mixture (is that the case?). Can the CS injector even open with an extra 28 ohms resistance in its current path? Maybe Brad could check on this?

Also, if the schematic representation of the thermotime switch is accurate, I don't understand why when cold, W-to-G would be 20-40 ohms, but G-to-ground would be 0 ohms. It looks to me like they should be about the same resistance when cold, as the current path would be the same. Out of curiosity, I just measured my thermotime switch (cold), and came up with the following readings:

W-to-G: 36 ohm
W-to-ground: 1 ohm
G-to-ground: 36 ohm

checkmate1996

I will definately be measuring the new switch to see what's up. But, another interesting thing is that my car seems to smell rich and there always seems to be 'popping' in the exhaust like extra fuel is being burnt.

hupp

Are you running a cat? If not, your shark will smell rich and pop to some extent even with a proper mixture. I've been there....