Hi guys I have a problem I have a camaro iroc z fuel injection and I have 2 codes #23- and code 54 the car runs and I can drive it but the engine it shakes a lil bit and rpm doesn't stay also when I turn the key on position the electric fan come on when the car haven't being turn on I can drive it and my coolant tempeture stays on 0 if I disconnect the relay the fan turn off and tempeture raise up but relay is constant on I replaced the relay with a new one but problem keeps there please help

 

23 = Manifold Air Temperature (MAT) sensor
(1985 and later vehicles)
Faulty
MAT sensor.
Faulty
or loose wiring and/or connections to the MAT sensor.
54 = Fuel pump circuit
(1985 and later vehicles)
Voltage
at terminal B2 is less than 2 volts for 1.5 seconds since last
reference pulse was received.
Faulty
fuel pump relay, circuit and connections.
Faulty
oil pressure switch.

start by monitoring fuel pressure at fuel rail for stability.

 

Ok and the problem with my electric fan that never turns off and is on even when the car is in on position I put new relay but keeps on all the time

 

time to trace wires and test what you have to start with. if you want to start with the fan yo have to chase out he wires, based on your earlier posts you have alot of problems. if they all lead you back to the ECM then try another ECM. don't throw parts and hail Marys at it. the fan circuitry is easy get a meter and start there.

 

I have power to the fan relay but there is a sensor for the electric fan to kick on and off ?

 

its slightly difficult to understand, and i dont get it myself but its real. there is a fan pressure switch that could be a problem. it is located at the lower RH rear corner of the engine compartment on the AC line. there is an electrical plug that goes to something on the AC line, it should have a green white wire and a black wire, just unplug it to see if the fan stops.

 

just did cam and lifters in my 85 tpi and i cant get it to run right wont hold idle .i changed out the maf now still the same .plug my reader in and no response from ecm.looked inside and noticed it had a hypertech chip in there,spoke to blue stresk in concord they said i need original prom how the f*** am i going to find that?called dealership and they cant help just a shoot in the dark does anyone know what else i can try

 

85s and 86s the rad fan is strictly controlled by the ECM. there is no fan switch.

 

tuned performance,,,, he can supply you with the correct MEMCAL. and if I were you ,I would change the ECM as well.

 

Fan running may be a symptom of ECU. When you jumper the ALDL it may turn on fans as well.

Key on engine off does you CE light blink then solid? If so it is running off prom and may be OK.

Is your CE lit while running?

If you repeat that test wait 30 sec.

Cam requires a tune as you know. TP will need datalogs .

 

There is an ECM override switch mounted in the passenger side block. It has a fixed on/off temp. Its a failsafe for the comnputer. It will turn on the fan if for some reason the ECM does not.

 

I just got the ecm back it was puched..the pretty good there it's called blue. Streak they were a little worried because it had a hypertech chip in there. Unfortunately I didn't have original prom the previous owner never told me that it was swapped out but I'll let you know tomorrow if it was the computer when I plug it back in...keep your fingers crossed for me..

 

apparently that's on 87 and up v8 cars. theres no mention of that in my FSM.