I have an a 89 vert. Car is completely stock. Was running good but now has some twilight zone stuff happening. Its an n/a manual.

so I drive the car on the highway going 70 and my check engine light comes on then the fc won't accelerate passed 70. Then I start losing power and the car becomes jerky. So I pull over turn car off. Check wat I can without tools and turn it back on. It runs good after that....for 12 minutes then it does it all over again. The idle is weird because it doesn't stay constant instead it fluctuates back and forth ffrom 1000-2000

 

so I was 2 hours from home when this happened and every 12 minutes id have to put the car in neutral, turn it off then back on again. In between that I had no issues. The check engine was coming on randomly before when id take my foot off the gas and the slightest depression would turn it off. That problem occurred at random intervals and did not happen at all today

 

For starters check for error codes, No? Chances are it's OMP related.

 

Haven't checked error codes because it hasn't happened consistently until now.

 

Even if it occured just once you would check for error codes as it takes maybe a minute of time.

 

?I can't afford one to own

 

Car isn't obd1/2

RX7 FD & Series 5 Error Codes

do the procedure for "S5" since yours is an 89.

-M

 

Will error codes come up after the light is off?

 

All you have to do is ground the single Orange colored wire check connector near the lead coil and w/key to on it will display any error codes.

 

I don't need an external device??

 

All you have to do is ground the single Orange colored wire check connector near the lead coil and w/key to on it will display any error codes. Making people repeat themselves is rather disrespectful.

 

I don't think he gets where the code will be displayed satch.

The check engine light will flash a pattern/multiple patterns, (series of short and long illuminations) write it down, check the link I gave you.

It isn't going to get more clear than that over the internet. Go do it and you'll see.

 

Thanks I we'll be back with an update.

 

I have error codes 27 and 12.

27 is the oil metering pump like satch said and 12 is something with the TPS. Should I replace these parts? Start premixing? I guess ill start looking for broken wires and connectors because both of these codes indicate electrical failure

 

Before replacing parts, test them to see if they have actually failed. Nothing worse than finding out after waiting a week of waiting for a part that it wasn't the issue. The S5 OMP uses the signal from the full range TPS, so crack out the FSM (fuel/emissions section) and read up on how to test it.

 

i would try adjusting the TPS, and unplugging the Metering pump, and making sure the connector looks good, and plugging it back in.

with code 27, the car will go into limp home, and the only fix is to replace the pump, or have the ECU chipped

 

damn I have a long drive tonight. I'm Oscar mike to test the parts now. Will update in a few

 

I tested the tps and it tested out okay.
http://www.johnr.com/tps.html using this page. It registered 12v on one side. I used the test connector by the airbox. Tps is good

 

So now that I've been driving and I go into limp home mode. Since the omp is toast should I premix now or what? Don't wanna cause engine failure

 

The full range wire to the TPS, Black/Green wire, should measure .8 volts at idle w/key to on and 4.3 volts at full throttle w/key to on. And of course the engine should be fully warmed and plug connected to the TPS.

You can drive w/o oil for a period of time w/o doing damage to the engine internals.

 

Damn well I still haven't been able to test the Tps in the way you explained. But for planning ahead, if I have to replace this part I'm looking at one for 500 bucks, anyone have any experience getting a used one? I've noticed my CEL is almost fully manipulated
by the gas pedal.

 

Time for a new ecu and mop. Or new ecu wirth rtek and premix.

 

A used OMP should not cost $500. Testing the TPS is easy so just do it and then when you have something of substance to talk about then others will talk.

 

I would advise against an used mop. It will fail in the same way. It's just a matter of time. And yes, running premix is a bit of a pain. I would open the ecu and look at the power transistor that controls the stepper motor. I bet it's cooked.

 

I gave up and took it to the shop. They tell me to replace the OMP now and fix the possible vacuum leaks before changing the tps. They didn't test the TPS though. I just gave them codes. The omp they have is used.