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Discussion Starter · #1 ·
Hi. I have a 89 Fox with CIS-E (1.8 8v). I want to know which sensor can cause my problem. The problem is while starting. Sometimes, the starter cranks but the engine won't start. It seems that the 5th injector stays open too much longer and the engine ge drown (In french we say "noyer"). The engine gets too much rich in gaz. Even with trottle body wide open it doesn't start. I unplugged the cold start injector, and it starts well. What could be my problem?
 

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Re: 5th injector problem (VW[Fox])

If I remember correctly from my ol Rabbit owning daze...there's a thermal sensor that's supposed to shut off the 5th injector when engine warms up. Sounds like yours isn't working!
 

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Re: 5th injector problem (VW[Fox])

The cold start valve should only stay on for a very short time right at startup and is regulated by coolant temperature. Your problem is most likely caused by a faulty CTS/TTS - That's "Coolant Temperature Sensor" / "Thermo Time Switch" - you should check according to your Bentley manual and replace the faulty component. http://****************.com/smile/emthup.gif
This only happens on warm starts, correct? If it's happening on cold starts, it's likely a combination problem.
 

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Re: 5th injector problem (VW[Fox])

Quote, originally posted by VW[Fox »
]Do you remember where it is
Follow line from 5th injector! On my old Rabbit Cabby it was right on the front of the block towards the passenger side. http://****************.com/smile/emthup.gif
 

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Re: 5th injector problem (The_Hamster)

Quote, originally posted by The_Hamster »
i believe the cold start valve only operates when the starter is operating.
if anybody can prove me wrong on taht i beg you to, as i am having a similar problem.

Hamster - Sorry to hear that you're having a similar problem...
I don't know what kind of proof you're looking for, but my Bentley
manual - Section 5.2 under "Cold Start Enrichment" states the Following:
"The electrically operated cold-start valve sprays extra fuel into the intake manifold for several seconds when the starter is actuated and the engine is cold. The valve is controlled by the thermo-time switch, located in the cylinder head coolant outlet. When the engine is cold, the switch is closed allowing power to reach the valve and open it. When the engine is warm, the switch is open and the valve does not operate. To limit valve operation and prevent flooding, the electric current also warms the switch and opens the circuit after a few seconds."
So, I would surmise that you guys have busted TTS's - The basic procedure to test the TTS is to hook up a test light or meter to the cold start valve harness connector, disconnect the coil, and make sure the light goes out / meter shows no voltage after a few seconds of cranking / being in the ON position - if the light does not go out, or the meter still shows voltage - the electrical heating portion of the TTS is broken, you can further check by letting the coolant come up in temp (there is a graph in the Bentley) and see if the CSV shuts off after this, but I'd just replace it if the electrical warming function is broken as you're just asking for later problems by enriching too long after startup.
Good luck!


Modified by Questor at 2:14 PM 9-17-2005
 

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Re: 5th injector problem (Residentevol)

Quote, originally posted by Residentevol »
do does the wire that gets the 12v come from the same wire that operates the starter solenoid?

I guess that depends on the year of your car - the wiring diagrams for my '86 shows that the Thermo Time Switch gets it's power directly from the ignition switch circuit, so I would guess that means that the 'hot' for the TTS / CSV is always on when the key is in the 'ON' position, and that the TTS opens and closes the circuit by manipulating the ground.
I believe on 1985 and earlier models, the power also comes from the ignition switch, however the cold start valve only gets power in 'START' but that the Thermo Time Switch is still present and active to defeat the enrichment in warm start conditions - at least this is what the Bentley indicated for 1985 - haven't checked the wiring diagrams for earlier models, but they are pretty similar - '86 was the 'big switch'

If the TTS is failing, it would seem that is is constantly providing ground to the CSV, and thus causing constant enrichment.
Notable is that according to these wiring diagrams, in '86-89 CIS basic cars (NOT CIS-E) there is an additional 'pulsing relay' that can provide ground to the CSV...
 

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Re: 5th injector problem (Questor)

well I was just trying to figure out if thats why my csv doesnt work because I had to re-run a wire from my ign switch to my starter solenoid so did this wire split off and go to different things or was it a direct hit to my solenoid?
 

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Re: 5th injector problem (Residentevol)

Well, the wire that actuates the starter is usually a single wire coming from the ECM/ECU, but check your wiring diagrams for your year, model, and country of manufacture to be sure. A bigger question is why the ECM is not making that wire hot when you move the key to the 'START' position...
Is your thermo time switch grounded properly? You can manually actuate the CSV with fuel pressure present by closing the cirvuit on the thermo time switch connecter and see if it squirts fuel.
 

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Re: 5th injector problem (Questor)

the wirign diagram shows the circuit path to go from starter, to tts, to csv. the starter power being from a relay inside the starter that is activated when the starter is cranking. thus the csv sprays constantly with the starter, until it's cranked for long enough that the TTS has heated up and broken the current path.
in my diagram (85-87 canadian cis), it shows another connector "t2a" that i cannot locate anywhere, nor can i locate where this connection goes to, as i can't find a matching set in any wirign diagrams.
does anybody know if there is a "pulsing relay" anywhere in an early CIS A2s, and where it is? vdubs found a mention of it in a mitchel manual, and we have found "cold start relay" mentioned on some obscure parts sites, it should be a 3 prong unit, like a flasher module. supposedly it becomes the current path for the CSV, after the car has started, for a few seconds.
 

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Re: 5th injector problem (The_Hamster)

Hamster,
I see the same thing - 85-87 Canadian CIS basic cars have the CSV wired off of the starter and TTS. Very different from our American CIS-E cars. Is your CSV harness hot all the time while running? That would seem to indicate that the TTS is providing ground and that the hot is active from the starter, which would be a double failure...
T2a is listed as "double, in engine compartment, near ignition coil" It looks to be an 'unused' connector, possible for diagnosis of this system.
I only see the 'pulsing relay' in US spec CIS cars, and I couldn't tell you where it is, except that it's not in the relay panel, or not indicated in the diagrams anyways - I'll try to look for it on the next '86-'89 CIS basic US spec car I run into - which is rare.
Edit: Spelling


Modified by Questor at 10:49 AM 9-19-2005
 

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Re: 5th injector problem (Questor)

i cannot locate the T2A anywhere, unless it is in the loom going through the firewall, which is just below the coil as you know.
no the csv harness is not hot constantly while the car is running, only when the starter is active.
if the csv is supposed to spray for a few seconds after startup, is it a constant spray? is it supposed to pulse?
the car used to start and run perfect down past -30C, now it starts and stalls at around +5 and below, starting instantly on the second crank and running fine after that, it's that shot of extra fuel that get it going again.
 

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Discussion Starter · #15 ·
Re: 5th injector problem (VW[Fox])

I have an update. I changed the brown sensor and the 5th injector still makes some free games. It happens that it still stay opened and it won't start untill I unplug the 5th injecor. Would this injector be the problem?
 

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Re: 5th injector problem (VW[Fox])

have you tested the thermo time switch? (brown sensor).
hook a multimeter to the leads to the cold start valve (5th injector), disconnect the fuel pump relay and the center distributor lead.
crank the motor and look for voltage at the cold start valve connector, it should go away in a few seconds, there is a chart in the bentley taht shows how long, with a cold motor.
if it doesn't go away, the switch is bunk.
also you can oull the valve out and crank the motor with the leads attached, it should spray a nice pattern, and not drip after it shuts off.
 

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Re: 5th injector problem (Questor)

The cold start injector only operates in the start position.
The injector gets power from the start position. It gets ground thru the TTS.
Start power to the TTS is for the heater inside of it. This is for the TIME portion of the switch. If you keep cranking when cold the TTS will still heat up and open so you don't flood out.
If you think you have a problem with the injector just pull it out and put it in a jar. Plug the hole up in the manifold and get somebody else to start the car while you watch.Do this with the injector connector plugged in and unplugged .
 

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Discussion Starter · #20 ·
Re: 5th injector problem (GDR)

I tested the injector as mentioned in the Bentley, with a multimeter connected on both terminals of the injector. Unplugged the coil and there is 9 volts when starting and it's constant until I stop starting. The Bentley says that at 68°F, the injector should operate from 1 to 3.x seconds but it's operating during all the time the starter starts... Don't understand anymore
 
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