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Opinions needed, car getting worse

Old 03-28-2013, 07:21 PM
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Opinions needed, car getting worse

So in my last thread, which generated no replies, I was having problems with poor idle and hesitation. Now it won't drive period, and when starting it up it will bog down and die within seconds regardless of its cold or warmed up.. I have an '84 turbo if that's any help, and it has been suggested to me that it could be one of a few things:

1) cts or more likely chts
2) fuel pump (its running rich with thick black smoke and smells of gas)
3) TVS (nothing changes when I pull it off)

I don't consider myself mechanically inclined enough to run ecu tests so if a few people could tell me where they would start I'll be satisfied.
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Old 03-28-2013, 09:51 PM
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Get the FSM

Here's a link to the service manual for your car. XenonZ31 Reference

This should give you some help in figuring out what might be wrong. On these older cars its important to clean all the connections, from the ECU to the MAF, etc. A proper ground is very important, you might consider a star or bar grounding setup to stabilize the old system. Good solid connections will allow you to trouble shoot any additional problems that might still exist. There are many great posts on restoring your car. Use google to search for these topics on zdriver and follow they're advice.
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Old 03-29-2013, 10:04 AM
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check your fuel pressure. (maybe bad fpr) TPS (TVS?). not your problem.
CHTS most likely cause. Vacuum gage to detect possible vacuum leak the bane of the FI engine but probably not the problem here as unmetered air causes a lean condition not rich. Disconnect O2 sensor (low down driver side aft) If she runs then you discovered at least one problem. I would ohm out the CHTS (procedure in the FSM that you are going to download and READ). You don't need to be mechanically inclined to do an ecu test. you need to be electrically inclined. If you can't do the simple stuff I suggest you buy a newer Honda accord and sell the Z to someone who can work on it. If in the Seattle area I would take it off your hands.
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Old 04-29-2013, 08:01 AM
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Check your MAF, also. I've had an issue alot like that, and it was just a bad MAF. I don't know about your intake setup, but the aftermarket intakes that use the charge spray will coat the wire inside the MAF and render it useless.
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Old 05-03-2013, 04:12 AM
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On a z31 when stuff goes wrong and u just cant figure it out for the life of you, check or change your o2 sensor this is what tells the pc in your car to run right this is overlooked a lot. Trust me! Check it 85z31 greddy blue drift car!
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