I dont know if this is normal or not. when I switch the key to on position without engine running, engine light stays on and and the red light that say check gauges stays on. but when i start the car all the way, no lights comes on... drives good except when I drive it long like 100 miles or so continuously and stuck on traffic, my fuel pressure gauge goes less than 20 maybe 18 or so, and the cars tries to accelerate slightly when even my foot is on the break (maybe trying to raise the fuel pressure). This problem been talked before but no one seems to know what the problem is, i thought ISO solved mine lol,, but it came back today. thanks

 

It's normal for your dash lights to come on with the key in the "on" but not "start" position.

By you saying that it tries to accelerate - do you mean when you're stopped or moving?

 

Are you talking about your oil pressure gauge? Your car wouldn't run with 20 psi of fuel pressure.

 

for the first question, it tries to accelerate while on stop.
for the second question, sorry for the confusion, i think im refering to the oil pressure gauge.. the one on the left right? yeah it is like belowe the 20. whats the deal.

 

another thing, i knwo the lights should come one when the key is on "on" position but everything comes on right and then everything goes off "except" for the engine light and check gauge light... is that still normal?

 

so the check guages light stays on? could be a slipping belt or bad alternator

 

My lights do the same thing. As soon as you start the car, they should go away. As far as the surging goes, you might want to look into a new fuel filter and maybe running some injector cleaner through the fuel system. My friend's auto car did the same thing, and after a new filter and some cleaner, it works perfectly now.

 

BTW my 94 Z have 76K miles on her as of rightnow. What kind of injector cleaner did your friend use? Last question, how hard is it to change the fuel filter,, or how much labor (dollar) is going to cost. thanks

 

Less that $20 bucks if you do it yourself. It's really easy. Just park the car for about an hour with the gas cap unscrewed to relieve the fuel pressure. Then jack up the driver side rear and scoot under there. The fuel filter will be the shiny tin can with hoses running to it. Simply remove the one hose that's bolted to one side and unclip the other. Then put the new filter in in reverse order.

I believe he used STP for a 16 gallon tank. You have to pour in the cleaner and fill the tank completely when you use it. You might check with some service stations, they have a treatment to flush the injectors that might help as well.

 

Thanks a lot man, im going to replace my fuel filter tommorow. any part number for the fuel filter or simply go to autozone and tell them fuel filter for 94 Z?

 

ACDelco #GF578

GM Part # 25121293

 

Thanks again man, also is my oil pressure normal to be at 20 when just normal driving (2 - 20 miles) at idle and then after driving for a lilttle while (about 100 mile continuously) oil pressure goes down to like 18 or 17ish at idle. And then this is when it starts to fluctuate in RPMs.. (RPM fluctuates from 600 - 800 to 1K and back and again) it seems like the car is trying to restore the oil pressure back to 20ish and it also seems like the car is trying to accelerate. One time when I was driving (since automatic) when I slow down I let off the gas, but when i let off the gas after two seconds, the gas pedal push it self down.. (not the whole way down but i felt it pushed down a lilttle bit and tried to accelarate on its own... ) what the hell is going on...lol

 

Spooky. Yeah, losing a little bit of oil pressure after the car heats up isn't a big deal, the oil is getting a bit thinner as it heats up. You might try going to a heavier weight oil next time you change it. I'm not sure why the car is surging like that, have you done any modifications to the intake like a bigger throttlebody or have you had the tranny rebuilt/replaced?

An example on the oil, I had a 77 Z28 that I built and I got a high pressure/high volume oil pump (was supposed to be just high volume). Anyway, when I first started it, it would have close to 100 psi of oil pressure, and after it warmed up, I would generally see between 60 and 70 psi. It made finding oil leaks really easy.

 

oh yeah man, I just bought this car like two months ago, and the ex owner said he has some professional rebuilt the tranny and install a shift kit while there at it. the engine is completely stock except for the K&N filter replacement. I use mobile 1 10W30

 

man something got worse today,,, I filled up my gas and im thinking its the tranny this time, but hell, i dont know. when i go to the highway and hit the gas, my rpm likes really sluggish on 1500 to 2500 its like having a hard time going up,, making the car stubmle until i floor this car and hit about 3000 rpm and then its fine,,, the ex owner told me that he rebuilt the transmission cause something was going wrong with it,, whats the deal.. any help is greatly appreciated. (it feels like it shifts out of first then stays on second and trying to shift to third,, the rpm on 1500 to 2500 is like bouncy not going straight up) PLEASE HELP.. I might have to go to the dealer for this one. thanks