I thought I'd be able to figure this out on my own, but I'm stuck. I recently picked up a 1989 Convertible for my girl. It has just over 100,000 miles. When we got it, it was flooded. I pulled the plugs and unflooded it. If you slightly depress the gas, it will start up, but you have to stay on the gas to keep it running.... it will rev, but seems constipated. It is running very rich. I've searched the site for a full week. What I've done so far is this: Learned how to test the compression... it's good.... Drained the old gas, changed the plugs and wires, found the oxygen sensor wire was broken, replaced that, found a cruise control cable was not hooked up and hooked it up.

Any thoughts or suggestions?? Thanks for any input

 

Checked for any hoses that are off?.It sounds like a vacuum leak.

 

You have an S5. Test for error codes.

http://www.banzai-racing.com/FD&S5_error_codes.htm

 

It's not giving any codes. It won't idle cold or once it's warmed up. Forgot to mention, it's n/a

 

Yes, I have been all over it.

 

What specifically do you mean by it "won't idle cold or warm." Does the idle bounce, and what is the rpm of the idling? And does the error code light flash once when you turn the key to on as it should?

 

I have 93 it 's doing the the same.my car is in the shop they say it the ecm because they can't pull the codes l did all the steps u mentioned.

Sent from my N860 using RX7Club

 

If i go to start it by just cranking it, like you would any fuel injected car, without touching the gas..it just cranks and cranks... nothing. If I open the throttle up.... by depressing the gas a little...it will start. At this point, still cold...if I let off the gas it doses not idle or go into any kind of "warm up".... I have to continue feathering the gas keep it running... once it's up to temp.... let off the gas and it still won't idle.

 

And yes, the light flashes once, then goes away. It does the exact same if I ground out the green connector by the battery also.

 

Sounds like you need to address the fuel supply aspect of things to help narrow down the cause of your problem. Could be a clogged fuel sock in the gas tank, clogged fuel filter, faulty fuel pump, faulty wiring to the pump, clogged injectors or even perhaps a faulty Fuel Pressure Regulator. Measuring the fuel pressure should probably be on your agenda.

 

I'm with you there.... just pulled the plugs, front 2 are dry, rear 2 are black....

 

Satch, I think he is saying if you let off the pedal it stalls but if you have it just slightly down it will stay running.

Pokesfan, have you checked the air filter or the tps? sounds like it might not be getting enough air or too much fuel. won't idle, sluggish/bogged throttle response.

I had similar experience on a piston engine, rodents had packed the intake and air box full of acorns, dog food and cat food. All the debris restricted the air flow so much that in order to get it running I had to keep the pedal at about half throttle and once it started I could let off *almost* all the way. As soon as I let off all the way it would sputter and die.

Good luck hope you figure it out.

 

Checked the air filter, it's good. I'm going to check the TPS and fuel pressure next.

 

And have you checked if you have spark from both coils? Also, after you check the logical things you might want to verify that the AFM flapper door is not sticking. And the Green/Red wire of the TPS should measure 1 volt w/key to on after the engine is as warmed up as possible.

When placed inline, the fuel pressure ought to be close to 40 psi w/the fuel check connector jumpered and key to on.

 

Yes, I have spark from both coils. I'll go check on the flapper door and TPS. Thanks for all your input.

 

For some odd reason, this time, I got it to give me a code: 18 - Throttle Sensor (TPS) Narrow Range - Fixed at full-open

Now what? Is this an "adjust" problem or a "replace" problem? Could this be the root of my main problem??

 

And now the fun begins.... I went to double check the code and it gave me these... in this order:

1 - Ignition Coil - Trailing ignition pulse cut
12 - Throttle Position Sensor full range fixed at 20%
18 - Throttle Position Sensor narrow range fixed at full open
8 - Airflow Meter - Basic fuel injection and fixed timing ( cripple mode )

 

It's going to be either a poor connection as the plug mates to the sensor or a fault in the wiring between the plug and the ECU or a fault in an intermediate connector between the ECU and the sensor/component or a pulled back wire in the ECU plug.

One of the best things to do is to gain access to the ECU and read the voltage signal from the proper pins and then compare them to the FSM spec. Most of the codes you listed are input signals to the ECU so the ECU is not receiving the proper signals for one reason or another.

EDIT: Pin 2's are in the smallest ECU plug, Pin 1's are in the second largest ECU plug.
Pin 2G - Full Range- Black/Green wire, .8 volts w/key to on,fully warmed engine.
Pin 2F- Narrow Range- Green/Red wire, 1 volt w/key to on,fully warmed engine.
Pin 2B- Air flow Meter- Green wire, 4 volts w/key to on.
Pin 1V- Blue/Green wire, 2 volts w/key to on, trailing coil.
Pin 1G- Blue/Yellow wire, 0 volts w/key to on, trailing coil.
Pin 1J- Brown/Yellow wire, 4.4 volts w/key to on, trailing coil.

https://www.rx7club.com/2nd-generati...wires-1013741/

 

Thanks Satch, that'll give me a starting point. I really thought one thing would be "bad" and there was a correlation between it and the others.... hopefully I can tace it down.

 

Satch.... if I don't figure this out, I may have to put you on the payroll.

 

Ok, I made a noob mistake with the codes above. I started thinking over my steps up to the point of getting the codes.... I ran the car, pulled the maf.... it died... then I ran it and pulled the TPS and it died.... but I never pulled the neg bat cable and reset everything. So, I just went out, pulled the neg bat cable and started all over. Now I have no codes and is still in the same shape.

 

Does your car have the emissions equipment (the BAC in particular) or was it "Deleted"?
Has it had the throttle body been tinkered with?

Sounds like the throttle butterflies are out of adjustment because it will stay running as long as you press the gas pedal. And the thermowax won't hold the idle up when it's cold.

 

Yes, this car is bone stock and all there. I don't know what the pervious owner did.... adjustment wise. I looked at the thermowax....standing on my head, with a mirror and it is in the exact same position...cold or warm.

 

When you mention reving the car is this in neutral or punching it while driving. Look at the piston which protrudes from the thermowax while the engine is stone cold and compare the pistons position to when the engine is warmed. Is there any difference between the two or is it in the same position regardless?

 

It dosen't run well enough to drive at all. Everything I've done has been sitting in park. The car is an auto. Yes, the piston looks the same.... cold or warm. I get no kind of "warm up"