HELP 86 maxima only idles

[cmarr]

This 1986 maxima 3.0L only runs at idle. While running, black smoke comes out ot the exhaust. When i step on the accelerator the car will die. I checked the computer and pulled three codes: throttle position sensor, engine coolant temp sensor, and air flow meter. I have replaced all these parts and the car runs the same. Thinking the ECM was bad I replaced it with another from a wrecking yard. Still runs the same! I have done a complete tune up, plugs,wires,cap,rotor, fuel filter,and coil. I have also checked for corrosion on all connectors. Got anymore Ideas???

[Nahkapohjola]

Originally Posted by cmarr

This 1986 maxima 3.0L only runs at idle. While running, black smoke comes out ot the exhaust. When i step on the accelerator the car will die. I checked the computer and pulled three codes: throttle position sensor, engine coolant temp sensor, and air flow meter. I have replaced all these parts and the car runs the same. Thinking the ECM was bad I replaced it with another from a wrecking yard. Still runs the same! I have done a complete tune up, plugs,wires,cap,rotor, fuel filter,and coil. I have also checked for corrosion on all connectors. Got anymore Ideas???

ECM is a lotteru machine.

Tst other sensors also: rev sensor, O2, Gas pressure (filter)

I suppose most sensors are equal to 3gen.

check out http://www.cardomain.com/memberpage/748507/9


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[flatire]

Originally Posted by cmarr

This 1986 maxima 3.0L only runs at idle. While running, black smoke comes out ot the exhaust. When i step on the accelerator the car will die. I checked the computer and pulled three codes: throttle position sensor, engine coolant temp sensor, and air flow meter. I have replaced all these parts and the car runs the same. Thinking the ECM was bad I replaced it with another from a wrecking yard. Still runs the same! I have done a complete tune up, plugs,wires,cap,rotor, fuel filter,and coil. I have also checked for corrosion on all connectors. Got anymore Ideas???

how many miles are on the car?it could need a overhaul.

[cmarr]

Thanks for the suggestions. Fuel pressure test good(35psi). will test O2 sensor. What does the rev sensor do???

[Nahkapohjola]

Originally Posted by cmarr

Thanks for the suggestions. Fuel pressure test good(35psi). will test O2 sensor. What does the rev sensor do???

Pressure is quite high, 3gen says around 30. Too high might cause injectors to leak...

First thin anyways is to do maintenace to ign: replace spark plugs, wires, cap.

Rev sensor gives ECU the timing pulse to figure out engine rpm and postion when to inject and ignite etc.

TPS may be gving faulty readings due to soot, clean, see how:
check out http://www.cardomain.com/memberpage/748507/6



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[cmarr]

This car has 160,000 miles. I suspect leaking injectors. I have done all tune up components. The car idles burning rich. The exhaust is black and the new plugs are already fouled. When i try to step on the accelerator and increase rpms the car dies out. Feels like flooding out. The car will restart fine. Your site is awesome!

[Nahkapohjola]

Originally Posted by cmarr

This car has 160,000 miles. I suspect leaking injectors. I have done all tune up components. The car idles burning rich. The exhaust is black and the new plugs are already fouled. When i try to step on the accelerator and increase rpms the car dies out. Feels like flooding out. The car will restart fine. Your site is awesome!

I suppose u have the service manual, online manual might be for u at www.autozone.com

Have u cleaned Throttle Body and Idle Adj CValve?

Is cold air valve working?

To die, all six injectors should behave equally. Quite unlikely...

Is ECU getting true +12V?

If the thing does not vary in cold/warm conditions, TPS is not the key.

The things common to all are MAF, distributor transistor & dist grounding, cam sensor (inside distr).

Suggest add distr gnd wire, and then get spares from junkyard.