First off I'm new to the forums obviously and actually new to camaro's generally and I hate to introduce myself by asking questions but I need a little help. I recently bought a 91 Camaro Rs with a 305, by no means do I expect this car to haul any type of *** at this point in time but it seems to have a absolute lack of Hp at all, also it's hard starting pretty bad on a cold engine, it takes 5-6 times to finally start, when I took the breather off it seemed the injectors were spraying okay when the car actually started but didn't seem to really spray when it was being started, also an engine service light popped up (don't know if it was related) and it appeared to be 23 code or a MAT sensor. I was thinking fuel regulator? I really don't know. Sorry if this is a novice question but I wanted someones opinion who knows more then me.

 

Does the fuel pump prime for 1-2 seconds when you turn the key to ON? You can usually hear it - might get someone to turn the key on while you have ear against gas tank (or the hump in the rear cargo area) and listen. If not, you need to look at the fuel pump relay.

The fuel pump relay is located on the driver side firewall, between the brake booster and the fender. There is a bracket there, with two 10mm bolts holding the bracket to the firewall. On the 'inner' side of that bracket, there will be 2 relays, one is for the fan (it will have a large black wire with red stripe), the other is for the fuel pump. You should be able to hold the relay in your hand and feel it 'click' when the key is turned on. If not, Mark the fuel pump relay with a sharpie, then swap it with the fan relay and see if it works then. If so, then replace relay. If not, then check the wiring and the connector for the relay to make sure no frays, scorched marks, etc.

In your car, the ECM controls the fuel pump. It sends a 12v+ signal on the green with white stripe wire to the relay that "activates" it - the ECM sends this for 2 seconds when key turned to ON to 'prime the fuel pump (ie send fuel to the injectors to start with). Then, after the car is started, the ECM detects a constant ignition signal from the distributor and constantly sends out that 12v+ signal to the relay, making the pump run always.

IN THE EVENT that the ECM or fuel pump relay isn't working, the Oil Pressure Sending Unit (OPSU) takes over fuel pump operation. When the OPSU senses oil pressure (takes 10-30 seconds) it will start running the fuel pump and thus bypass the bad ECM or relay. That's why it often takes several starts, or a long cranking period, to get the car started. Make sense?

On the slowness - might just be the 305. These 305 TBI motors only make 170hp - they are definitely no speed demons!

https://www.thirdgen.org/service-eng...ht-error-codes

Code 23 might also be a TPS issue. The TPS is adjustable to a degree, and there's a way to test it with a digital VOM. I don't know all that stuff off top of my head, but if you TPS you'll find alot of threads discussing the TPS, it's adjustment, and voltage checking.

Good Luck! And welcome aboard!