rbrewers

I have a Service Engine Check light coming on. When I checked it I got two codes 02 and 03 which is the CAS, on both codes. I found one CAS, could someone tell me where the other one is on a 1990 Mazda RX7 non turbo.

diabolical1

iTrader: (3)

welcome to the board.

there is only one CAS. i'm not sure what led to believe there were two, but for what it's worth, it handles both Ne and G circuits.

rbrewers

The engine trouble code shows 02 and 03 and says

o 01 - Ignition Coil (Trailing) - Trailing ignition pulse cut
o 02 - Crank Angle Sensor (Ne) - Fuel Injection and ignition cut
o 03 - Crank Angle Sensor (G) - Fuel Injection and ignition cut
o 08 - Airflow Meter (AFM) - Basic Fuel Injection and fixed timing (Cripple mode)
o 09 - Water Thermosensor - Coolant temp fixed at 176F
o 10 - Intake Air Thermosensor (AFM) - Intake air fixed at 68F

So there is just one, but it shows two different codes? Like above?

satch

iTrader: (1)

Because the CAS is responsible for creating two signals which means you can get as many as two error codes total. Check the condition of the plug connection. Clean if necessary and make sure each wire in the plug is not pulled back which could cause a faulty connection.

And has the car always had these codes since you owned it or did it pop up just recently? And have you performed any work on the engine recently.

rbrewers

Thanks so much for the ifo, when I got the car the engine light was coming on. It goes off when I drive it, but comes on during idle. I haven't done any work on it at all. It also puts out a lot of white smoke when I try to start it.

rbrewers

I need to put the cas in and I see that I need to align the yellow mark on the pulley, is there an easy way to do that? Do I need to take the belts off to line up the yellow mark? How easy is it to turn the pulley without removing the belts?

satch

iTrader: (1)

You can use the alternator pulley to rotate the engine to the proper timing marks.

rbrewers

thanks I'll give it a try

rbrewers

Worked good, now the lines aren't colored. It the one on the right yellow?

satch

iTrader: (1)

Yes.

https://www.rx7club.com/2nd-generati...estion-978911/

rbrewers

Sorry but I have looked and looked, do I need to replace the, It's called blind cap on the diagram, and if so what is the size of the bolt and cap nut?

satch

iTrader: (1)

Why do you need to replace the cap for?

NoddE

Somewhat related.. Ive noticed that both the rx7 and the toyotas uses the same names for the cas signals (NE and G) and i believe that the rx7 has 24 teeth on the cas right? So is it the same kind of cas or signal on the rx7 as it is on the 24t toyota 3sgte engines with distributors?

rbrewers

Folks I feel dumb asking this question but here goes, I tried to unhook the wiring on the cas and it wouldn't come loose so I tried a screw diver under the front side. The casing on the connector cracked. I don't want to destroy it any more. Can someone tell me how to unhook the wires without destroying the connector?

diabolical1

iTrader: (3)

there's a tab that you need to pry up away from the clip itself (finger, screwdriver, etc.), then just pull the two sides apart.

EDIT: oops ... just realized that you said you want to unhook the wires. well, you'll need to separate the clips to do that.

rbrewers

I got the CAS changed out and the engine light is still coming on. I checked the old one and it is fine so I'm putting the old one back in. I'm wanting to check the timing. Could someone tell me how I find the number one plug to hook the light to?

diabolical1

iTrader: (3)

the number one rotor is the front, and you'll want to use the lead (L) spark plug.

do you have a copy of the FSM or some other technical/repair reference?

for ideas on why you're still getting the codes, hopefully Satch will provide some insights. I currently have none.

rbrewers

No, I don't have any idea's. I put the cart in front of the horse when it gave me the 02 and 03 engine code reading, which said the CAS was bad, I bought one. Then, thanks to the rx7 site here I found out how to check the old CAS. It said I should get a reading of between 110 and 210 ohms across the connectors and I get 150 to 160 with a shaky hand. 8-) I'm going to hook a timing light to it after while, the battery went dead while it has been setting, and now it's on the charger. I don't have any manuals, the ones I find online don't really tell me about the number one plug.

satch

iTrader: (1)

Did you measure the ohms at the CAS or at the ECU? The wires from the CAS run to the ECU so the readings there are more relevant than a reading at the sensor connection, especially since the sensor sends signals to the ECU. You would pull the largest plug from the ECU which houses the CAS wires before ohming the individual wires. And when looking at the ECU plug you could also determine if any of the CAS wires are pulled back in the plug and not making a good connection w/the ECU. And close to the ECU is a Grey wire which is the CAS shielding. This wire should be grounded.

rbrewers

Well I'm back to work on my 1990 Mazda RX7. I've been traveling and now back home wanting to work on my Mazda. I'm still having the service engine soon light problems, see above, and now to start it I have to pump, and pump the gas. Now the add coolant light is coming on for no reason. Just wondering if anyone has any ideas what to try next?

rbrewers

Ok then.. I guess not....

diabolical1

iTrader: (3)

the coolant light thing is probably a broken/breaking sensor wire.

for your CEL, did you do all of what Satch suggested in his last post? also, where is your timing?