I was driving my '90 to work this morning after having done some changes, and got the "Full Engine Power" light as well as the SES and Service Ride Control. Here is a list of what I did.

1) Removed AC condenser, pump, lines, but still have the box on the firewall. This involved switching to the clockwise rotation water pump and shorter belt.

2) Installed oil cooler via sandwich adapter, and accusump in the return line.

3) I mounted the accusump in the location of the battery and removed the cruise control servo and plugged/removed the vacuum lines.

4)Relocated the battery to the compartment behind the driver's seat.

Now the only connectors I delt with were the cruise control servo and the connector on the AC pump. I did not unplug or touch anything else on the engine. Since I had to drain the coolant I assume( I havent had a chance to run the codes) the SES light is a code 15 because I fought that code for weeks when I replaced the temp sensor and had a bubble by the sensor that caused the code. It went away after a few coolant burps and refilling. Now the "Full Engine Power" light I have never seen before. What does it mean? Have I been racing all this time without all of my power?

The only running the engine did before today was to check for leaks and such while it was on jackstands. Anyone know what the issue may be?

 

Is this an L98?

 

Its an L98 with a ZZ4 cam, 30lb injectors, Headers and 3" duel exhaust. All those mods were done a while back and a chip was burned for them. The only things I did now were listed in the first post. Nothing was done to the engine though but water pump, oil cooler and accumulator. Nothing with sensors.

 

Strange one...

That light is for ZR1 LT5 cars when the key is in the "Full" position that light is supposed to come on.

Why it is coming on for an L98 car is a good mystery.

 

This is weird then... I guess they use the same light cluster in the Z? So even when this light is on in the Z its not a bad thing?


Im almost certain the SES light is from the coolant being drained but I will check tonight. The car is showing the same characteristics, ie rough idle when cold, as when I replaced the sensor and had to burp the coolant. Once warm the car seems to be running great with no issues.

 

hmmm...check the VIN, think the Zs had a J in the 8th digit.
Wonder if at one time someone seriously changed that car you have.
Shot in the dark.

 

Are you saying someone would go through the trouble of narrowing a Z and installing an L98? The back wheels are the GS offset and work well. The RPO codes under the storage lid make it seem like it should be an L98 car. I think it would be too much trouble to go backwards, but now you have me thinking... I will check when I get a chance.

 

Well the DIC does have some overlap. For example all LT1 cars came with a PKE light in the DIC even though the early ones didn't come with PKE hardware installed. (And some non-FX3 cars have SRC lights too.)

It is just possible that the DIC was swapped at some point. Maybe some L98 and LT5 cars got the same DIC and yours is just now exhibiting some crossed wires?

Maybe someone else with a '90 L98 will shine a flashlight at his DIC and look for the light?

 

I hope wires arent crossed. I only unplugged the cruise servo and AC pump.

If anyone would do that the light is in the middle column at the top. If you go from the SES on the bottom of the column all the way to the top light, thats it.

EDIT: Also, mine does have the FX3 controller and I get the service ride control when the car runs on jackstands and the suspension is unloaded. However this time it stayed on.

 

See if your SRC light goes out after you drive the car a couple of times. IIRC three starts without moving the car can set the light.

 

I have the full power in my DIC. The interior is the same for the ZR-1 and the L98 with the exception of the full power key in the dash. This is a strange one!

 

If it is the stock 90 DIC whats happening is impossible. here is why, this is the DIC out of my 1990 as you can see with all bulbs removed some spaces will not show anything because the back screen is blacked out in those areas anyways. So even if a bulb was present and a electrical short occured it still would not show anything anyways. Here is my DIC with all bulbs removed and against light notice the area you say illuminates full power light cant possibly do that if its a L-98 DIC.

also if the car didnt have LTPWS there is no printed circuit for it anyways .... You would have to have a ZR1 DIC

 

That would make sense

 

What is the Vin engine digit?

 

Just double checked my DIC and I also have the Full Power indicator, top row, third from the right. It is possible, as even the circuit board above shows power going to that location. Possibly all 90's up to a certain build had the same DIC as the ZR-1s...

 

Sorry guys I have not had the chance to be at a computer for a while. The car is in fact not a Z, and for a little while when driving yesterday I had no lights at all, and then they all came on again. Normally they all come on when I start it. The SES light is in fact a code 15, water temp sensor, as I suspected so there is nothing faulty with the engine to give the Full Power light. At least nothing that would throw a SES code. I have tried unplugging the battery to reset the lights but they come back on.

On another note, I was out driving and the seal on the back of the waterpump (brand new just put on) broke. So now I have to fix that before I look into other things with the lights.

 

I have driven it several times with, and the light comes on every time. I am thinking the SRC and Full Engine Power are somehow related to a single problem? A new secret coding system maybe...