My check engine light comes on only when drivning on Freeway for 5 min or so...
But when I come to a stop and turn off the car and start it right back up, the check engine light always goes off... But will come back on when driving back on freeway. It doesnt seem to come on when driving in city... What could this be??

Thanks guys..

 

Find out what code the engine is pulling by turning off your car, then turn the key to acc the spot right before start. Watch the cel every long blink is a number in the tens digit and every short blink is in the ones digit. For example you get 3 long blinks and 7 short blinks that is code 37. Look at this link for more detail and the codes that you pull.
http://www.scuderiaciriani.com/rx7/engine_codes.html

 

Some of the CEL code lists don't show code 13 which is the EGR valve and most likley (because it is so common) could be the problem. I had the same symptoms and that is what it was. I have been told it's not worth the fix because it will fail again. I recently put in the PFC and I think that is a wire that is cut so it no longer works anyway. Definately check it ASAP to remedy the problem. Anyone have any other knowledge about any problems with not replaceing the EGR other than the CEL being on?

 

gbomb91, I've got the CEL 13 on my car and would like to know how to fix it, or at least get the car running again. Any thoughts? Thanks

 

first of all, I was referring to 16 not 13. My mistake, 13 is the pressure sensor on the intake manifold. I also had this and Rocky @ rx7.com was the only person who gave any insight. you either have a bad sensor or it could just be loose at the connection like mine was. My car never stopped running,l i just fiddled with it and made sure the conncetion was on correctly. By the it is located on the back side of the UIM. I would check the shop manual for it's exact location and make sure it's connected tight. It may need to be replaced and it seems to be a common problem. Search for CEL 13. Again sorry about the mistake, the EGR is 16 and that is what I was refering to fd3s RX7

 

gbomb91, thanks for the quick reply. I will check out the workshop manual. Thank you

 

I had a check engine light and it was the o2 sensor wire loose, check your codes

 

I just got a stupid check engine light and it's 23 Fuel thermosensor. What's the deal with that one? Does it actually go bad?

Amel

 

SES light can be anything lol. However it does sound like the EGR is malfunctioning. Since normally it will only open during cruising speeds (highway).

 

Yeah that's what I'm thinking too.
The EGR., CAuse it only comes on during cruising on Highway. for 5 min. or so..

 

How do you do the dianosis. Because I turn the key to the accel. and no CEL blink??

I'm confuse. What does this mean??
With the car turned off, open this box and bridge the terminals named "TEN" and "GND" ( i think the terminals are labeled under the cover of this box) with some wire.

Thanks

 

Never mind,
I had figure it out...

I pulled a code of

15 and 17

15 was Oxygen Sensor, and
17 was Feedback System for O2 Sensor...

What is 17... What is the Feedback System???

 

okay,
never mind, it was the O2 Sensor itself.
I installed it, and disconnect the negative batterie and wolla. No more code error.
I'll test drive the car tomorrow morning and see what happens. Hopefully my gas mileage will be back to normal. Because right now, I'm pulling 9 MPG...

 

If it comes back then you have an intake leak. Too much O while at vacuum and the O2 sensor will read above 1 volt triggering the 17.

 

it is because the o2 sensor is not switching. maybe old maybe wiring. i hate to prescribe the shotgun approach but a new o2 and an ecu reset would be simple and fast. look at the connectors. you can look at the o2 voltage do you have a multimeter

 

I got this same exact problem; only get a CEL while I drive on the freeway for over 10 minutes. If I turn off the car,and start it back up, the CEL would go away.

I tried to do the diag test. By hooking up the TEN and GROUND positions. I didn't get a code. I did this when there is no CEL on.

I can't get the CEL *anytime* after I restart the car. I am guessing this is why I am not getting a code.

Any ideas?

TIA.