Engine Codes
 

I recently plugged the Snap-On computer onto the FD to check the system (won't start, has good compression, good spark, fuel).

Here is the list of problems the computer displayed.

Engine codes:
09 Atmospheric pressure sensor circuit
11 Intake air temp sensor problem
12 Throttle sensor or circuit problem
13 Vaccum sensor or circuit problem
20 Metering oil pump position senor
23 Fuel thermosensor open or short circuit

.... I don't even know where to start, for #20 I think I need a new oil sender. But I don't know what the others are about...

Any ideas?

BTW this is my first time owning an FD...

Anybody know a good Rotary Shop close to Havelock, NC???

I've dealt with two of those issues.
Intake Air Thermosensor is easy enough, but you'll have to pull the upper intake manifold to access the sensor. The Metering Oil Pump sensor is part of the metering oil pump assembly and, as far as I could tell it's more practical to change out the whole thing.
----> https://www.rx7club.com/3rd-generation-specific-1993-2002-16/changing-oil-metering-pump-omp-while-car-my-how-675341/

Have you first disconnected the battery to reset the codes, and then restarted the engine and verified that they do come back? The PCME will remember the codes forever once stored, even if the problem has gone away, unless it is de-powered.

Yup, disconnected the positive terminal on the battery and press the brake a couple of times before I test it.

Thanks! Got 2 down and now those stupid "circuit" problems...I will have to go through the wiring diagrams...what a pain.

Anybody have any clue on where I should start looking for these engine codes:

09 Atmospheric pressure sensor circuit
12 Throttle sensor or circuit problem
13 Vaccum sensor or circuit problem
23 Fuel thermosensor open or short circuit

Anyone?

9 - Water thermosensor is the upper sensor on the back of the water pump housing.

12 - Throttle sensor is going to be the TPS on the throttle body

13 - Pressure sensor is going to be the MAP/BOOST sensor located on the firewall on the drivers side.

23 - Fuel thermosensor is the sensor on the secondary fuel rail

Thanks Mahjik for the info.

Should I just replace these items? I'm going to try and pull the wiring harness, and test everything this weekend.

But "14 Atmospheric pressure sensor (built in ECU)" how the heck I test that? Should I just bring my ECU to Autozone and have it checked out?

Sorry I'm such a noob to the FD, but this is my first car.

with my experiences with OBD-I cars, is that engine codes are usually popped up when there's a short or open in the sensor's circuits. i could be wrong, but that's only me speaking through experience :dunno:

You aren't getting code 14. Most likely the Snap-On reader doesn't have the proper labels for the codes. You were getting code 9 which is Water Thermosensor. You are also getting Fuel Thermosensor. Those two sensors are identical sensors, just used in two different locations for two different liquids.

What you should do is:

Check the plug to the Water Thermosensor. If its not connected onto the sensor all the way, then you found your problem. If it is, you need to test the connector to see if voltage is getting to the sensor (use a multimeter). If that passes, then you need to test the sensor (procedures are in the FSM). If that passes, then you most likely have a damaged wiring harness.

Just start with the one sensor first because if its a wiring harness problem, there is no sense in testing the others.

Ahh...thanks very much, will start the testing this weekend, got work and school this week...