Hey thirdgen'ers, I've got another one for ya. on My 89 pontiac firebird, today I was on my way to the shop and was stopped at a red light, turns green go to take of and went NO WHERE! It was pretty embarrassing, I had people behind me and it was like I had little to no power. If I stomp on it it will take off, but on normal acceleration I lose power. This happens for about 10 minutes or so until it warms up all the way, after that everything seems fine. What's happening here? I just replaced one injecotor, there both spraying great, nice even cones on both. Fuel pumps new, new spark plugs. It isles fine, nothing out of the ordinary. Thanks in advance for any and all replys... -Matt

OH! And I have no thermostat in it right now, but I don't think that would cause it, right?

 

No thermostat in an EFI car? Yes it will have a severe affect on performance. Why is the t-stat out? Is there a cooling sys problem? Put a thermostat in it. Also, how are your ignition wires?

 

I had a thermostat in it, but I had this weird problem where the gauge would say it was running HOT after only a couple minutes of running, the needle would be in the red. So I took the thermostat out just to be safe, didn't want to over heat the motor. And it seemed fine ever since, never had the gauge problem again.

 

Just put in a new thermostat, still havin the acceleration problem, not as drastic now that the weather is a little warmer. It seems like it only really happens when its cold outside.

 

Check out your inlet air temperature sensor. It should be in the air cleaner. It measures the temperature of the air being drawn into the engine. Cooler air contains more oxygen, therefore requiring more fuel to maintain AFR. If the sensor is misreading the temp of cool air, it can cause the engine to run lean or rich at cooler temps. This will cause a loss of power. See if the sensor's dirty or otherwise obstructed. The sensor can be tested for resistance. It should read 7,500ohms at 40degreesF, and 3,400 at 70degreesF.

You should really have a scanner for issues like this. There are a few possible causes of this type of issue. ECM data would likely reveal the cause very quickly.

As far as your temp gauge is concerned, they are notorious for becoming inaccurate with age. It may be the sending unit, which is installed in the driver's side head, between #1 & #3 spark plugs. Or it may be the gauge itself, more likely the gauge. They can be rebuilt. Yo can also fix them with the right resistor.