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Make sure you have the thermotime plugged into the thermotime harness and the temp sensor plugged into the temp sensor harness.


You wrote down 54 3.3
I assume this means a temp of 50f and 3.3k or 3,300 ohms when reading pin 13 to ground at the 35pin connector. thats pretty close


but then you have 150 2.3
again assuming you mean 150f 2.3k or 2300 thats way off should be in the hundreds not thousands of ohms.


You should remove the temp sensor and to a more controlled test. Also make sure you have it plugged in right and then do the test again at the 35pin. A new one is a good way to go, as you can compare them side by side.


True the thermotime switch is not cheap, but owning a 40yr old car is going to cost so you may as well get used to it.
Yes it only operates the cold start during the "start" position of the key but what the heck if you take care of the little details as they come up it will be less variables to consider when you do have an issue. You should have already pulled the CSV valve out placed in it a container and confirmed its operation including leaking or not.


pressure should be 36psi when the pump is on but the engine is not running. running it should be closer to 30psi, and it should vary with the throttle position (engine vacuum).


Your leak down of pressure sounds the same as mine, it can vary but as far as being an issue, if the pressure comes up to full after a couple seconds of cranking, I doubt it is the issue.
 

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If those numbers are correct esp the 150f then that will cause very rich running, foul the plugs and most likely a major contributor if not the only problem with rough running. You should be getting the correct numbers AT the 35 pin connector. Until you get that sorted out no reason to move on with diagnostics.
 

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Discussion Starter #23
If those numbers are correct esp the 150f then that will cause very rich running, foul the plugs and most likely a major contributor if not the only problem with rough running. You should be getting the correct numbers AT the 35 pin connector. Until you get that sorted out no reason to move on with diagnostics.
Sorry for the delayed response, it has been a while until I could get back to my car but I have good news, its pretty much fixed.

The main source of my problem was that water temperature sensor that controls the fuel injection. I swapped that out and now the car starts right up and has no problem idling and I can rev it up right after I start it, no dieing. Its crazy how such a simple part can make an entire car un-driveable.

In case anyone else has a similar problem and is thinking about replacing the water temperature switch it is very affordable, it only costs $15 at Autozone.

For my situation, the old water temperature switch was causing the fuel mixture to go lean during start up and causing the car to die and back fire until it had warmed up. I believe it was also causing a rich fuel mixture after it was warmed up, indicated by the fouled sparkplugs and sensor test but that is yet to be seen. The car does still "putt" out the exhaust some so I might still have some rich issues is my guess.
 
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