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Discussion Starter #1
Hello,
I have a 89' spider with bosch injection. I had a lot of problems with idle. After repairing all the leaks, i have a good idle.
But i saw my vvt isn't functionning. I put +12V on solenoid and it works fine. I try ro repair the pigtail plug but it doesn't work.
With full throttle and solenoid unplugged I have 8 volts on yellow wire. But if I try to put a relay or something between yellow wire and ground, the voltage drops around 3-4 volts. I also try with a solid state relay but it's the same thing.


Anyone ever had this problem ?
 

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Hello,
I have a 89' spider with bosch injection. I had a lot of problems with idle. After repairing all the leaks, i have a good idle.
But i saw my vvt isn't functionning. I put +12V on solenoid and it works fine. I try ro repair the pigtail plug but it doesn't work.
With full throttle and solenoid unplugged I have 8 volts on yellow wire. But if I try to put a relay or something between yellow wire and ground, the voltage drops around 3-4 volts. I also try with a solid state relay but it's the same thing.


Anyone ever had this problem ?
What solid-state relay did you try? I've used that setup for many years, and it is still working well.

 

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I tried with this solid state relay. When I don't plug anything on the output i have continuity between the two output pins.
But when I put the green cable ou the ground on output, i doesn't work.
The voltage at input pins (ground and yellow wire) drops to 4-5 volts. Can the problem come from the car wiring harness or the ECU ?
1629573
 

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I tried with this solid state relay. When I don't plug anything on the output i have continuity between the two output pins.
But when I put the green cable ou the ground on output, i doesn't work.
The voltage at input pins (ground and yellow wire) drops to 4-5 volts. Can the problem come from the car wiring harness or the ECU ? View attachment 1629573
When no wires are connected, there should be an open circuit between the output terminals (1 and 2). If you have continuity between those terminals with nothing connected, then it may be a bad relay. Separately, the relay you have has a very high current rating (80A), which may have some impact on the operation (a guess--I don't know). What I do know is that the standard electromechanical relays (Bosch-type) I tried for this application did not work because the triggering current was insufficient to trigger the relay. The SSR I used had a rated current of just 10A.

Can you confirm that you have 12V on the green wire (unconnected to relay)?
 

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To follow up on this, I found another 10A solid state relay I had put away, so I did some testing to show how it works in my car. Below are the wiring diagram for how mine is connected, a photo showing an open circuit on the output when no voltage is applied across the input terminals, and a photo showing minimal resistance (closed circuit) on the output when a voltage is applied across the input terminals.

1631505

1631506
1631507
 
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