1G Some electric doubts and code errors.

[Albardo97tg]

Hi everyone, two weeks ago I bought a 1G 1992 with some issues as a project car. Slowly my father and I have fixed everything we could, but now we are stuck. I have three problems.

1- The 1st one is that we found a connector that does not seem to fit in anything near to the battery. I don't know certainly if this is the ignition timing adjustment connector and if it is normal to be alone or not.

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2- We found a loose wire near to ISC if I'm not mistaken. I tried doing some research but I found nothing.

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3- I have 3 code errors from diagnostic port 13, 21 and 25. I know that 13 and 25 are from MAF. 21 is from CST and I've replaced it 2 times but still receive this code. I don't know if this errors could be related with 1st or 2nd problem. Before replacing MAF (if it indeed have any issues) I want to fix the 21 code error. In the electric manual I found that MAF and CTS are connected into the same sensor ground wire.

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On dashboard CEL is ON, cold start is difficult and idle is slow (about 500-700RPM) at first but after 15 minutes of driving idle is near 2000RPM and car starts without problems.

Thanks u for the help.

 

[pauleyman]

You are correct about ignition timing. Usually there is a cap on the connector. The 2nd wire looks like idle positionn switch since you have no wire to the switch. It's right next to the throttle body spring.
Last one check the codes again. 3 codes and 2 of them are mass air. This usually happens and all 3 are mas air because the car was ran without mas plugged in. You'll get mas air. Intake temp baro pressure. Make sure you didn't read a code wrong. You could still have a it's issue. I would clear it and check again.

I would expect 12, 13 and 25. I don't usually suggest throwing parts but CST is cheap enough you could just change it. Check harness too. Could be corroded, broken etc. There are also two CST. One for ECU, one for gauge.

 

[steve]

I notice on your throttle body you are missing the Idle Position Switch or the top half is broken off. That may be what your loose wire is for but I can't see the wire in your picture. If it's a solid green wire going back to ECU pin 14 that's likely it. Here's a 1G NA TB, the IPS is under the black boot.

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Once you get a new IPS and connect the wire you'll likely get idle surging if you idle when warm is 2000 rpm.

 

[Albardo97tg]

Thanks for the answers, I'll try to connect that loose wired into de IPS. About the error codes I'll do the scan again, clean MAF and check harness. The CTS I'm talking about is the ECU one, and have 2 pins in T form. I'll keep you up with any updates.