OK so I have a 90 camaro rs with a 305 timing is dead on no miss firing compression is good fuel pressure is good everything is good to the best of my knowledge car runs perfect on short drives, let's say up to 20 miles, until the car reaches about 220 degrees and the I try to put the pedal down and I have no Power what's so ever like sometimes its hard to get it into second having no power to get to a high enough rpm so again the engines runs perfect until it reaches 180 to 220 my thoughts where its over heating and my gauge isn't working properly but it seems to be about right I know that around 160 to 180 the car goes into a closed loop and some things open some things close. I'm pretty mechanically handy I've done a lot of work on various Chevy motors in the past but this has put me into a funk please help me get my sanity back cause its causing problems in my daily life seeing as I've screwed things up at work trying to think of the problem and if I were married it would most definitely cause problems in my marriage so thanks for the help ahead of time

 

My guess is the fuel system is dirty / clogged and or the fuel pump is old and tired.
Either way the fuel pump is getting close to retirement.

Have you replaced the fuel filter? inspected the fuel lines /tank for debris? how old is the fuel pump? If you answer No / I don't know, this is a good place to start.


These cars are made to run at 190-230 degrees, if you overheated you would know because the overflow would have "boiled over"

you say the fuel pressure is good, how do you know that? is it good at idle only?
How about when you give it throttle? how about after the car warmed up?

TPI cars have a Schrader valve on the fuel rail to connect a fuel gage, Throttle body cars you will have to cut the rubber line and install a "tee" fitting to test the fuel pressure.

Have you checked fuel pressure after you have this problem?

 

I haven't checked the fuel pressure except at idle so thanks for the feedback it looks like I'm going to invest in a fuel pressure gauge. I changed the fuel pump about 8 months ago and you think temperature would really affect my fuel pressure?

Any recommendations on a decent fuel pressure gauge that best suit my tbir

 

As the car runs & warm up... so does the fuel pump.. if the lines are clogged /restricted (supply return or both) the fuel pump works harder to overcome the restrictions.

The pump works harder and overheats (it is submerged in fuel but worked hard enough it will still overheat) when over heated it runs slower and fuel pressure drops.


quick test: if you checked fuel pressure at idle.. rev up the engine by hand and watch your test gage.. fuel pressure should remain steady.. if pressure begins to drop you have a faulty pump or restriction in the lines. Did you replace the fuel filter when you replace the pump?


I use an autometer pro-comp mechanical fuel pressure gage mounted to the cowl with a gage cup, but I have cowl induction hood and carb.

You could do this with the stock hood but may not like how that looks.

if you install the gage on the a-pillar with a pod you need to use an electronic gage or a mechanical gage with isolator.

For an otherwise stock car I would not bother, just do your diagnostics...

but don't say fuel pressure is good, if you did not test it. Pressure at idle means nothing if it drops the second you give it throttle...

 

I see thanks for the info I'll let you know what happens