White Spark plugs a low vacuum at idle

[blackrosenova40]

i have a 1990 Gsx and I only pull 7 inches of vacuum and my spark plugs are pure white.

My Eclipse will not go past 3800-4000 rpm , it feels like a brick wall, I wont dare go past it , feels like I will kill the engine

I did a compression check the read as follows

#1 152
#2 154
#3 162
#4 164

My car currently has 13300 miles on it and it has been checked for vacuum leaks and there are none. It idles smoothly but low vacuum which I find odd.

I just replaced the fuel filter and when I took of the top hose on the filter there was barely pressure, in fact it just kinda dribbled.

Could my fuel pump be bad? I dont know what else could be wrong, perhaps my computer is malfunctioning. Please help i cant figure it out.

Thanks in advance -Chad

Ps: My valve timing and ignition timing are right on also.

 

[jhines]

Alright, that sounds like it would most likely be either fuel or ignition related, but you said you did wires and checked the ignition, right? WEll do you have good fuel pressure? Check it at the rail and make sure that you have a good pressure.....not sure on the spec., but I'm sure someone on here knows. You could have a ECU issue with the load also. Not sure what else it could be, those just seem to be the most likely to me. Someone else might have some better info, but I hope that may help narrow it down a little. Aight man, good luck to you.
-Hines

 

[blackrosenova40]

Yeah im gonna buy a fuel pressure gauge tommorow, if the fuel pressure reads bad , then im gonna check voltage to the fuel pump , if its good, then fuel pump is bad, otherwise im guessing the ecu is bad or something similar.

Is there a possibilty of a stock fuel pressure regulator bieng bad?

 

[jhines]

I haven't really heard a whole lot of the regulators going out, but I guess it could. But check your voltage supply and have you checked the filter to see if it is clogged? But yea, make sure that you have good fuel supply and then I would look towards getting another ECU from a known good car or something to try in it before I run out and buy a new ECU. But yea......definitely sounds like a probable fuel supply problem. Se what that rail pressure is and post your results.
-Hines

 

[blackrosenova40]

Ive put in a new fuel filter a couple days ago.

 

[blackrosenova40]

Werll I finally installed my fuel pressure gauge (B@M), and it is reading at around 32 at idle, and it reads up to 40 when I take the throttle slow to around 4000.

Anyone have any opinions?

 

[silvercoupe97]

Another thing to consider (fuel related) is that you could have some tank debris, kinks, or even a clog in the lines from the tank to the motor. With that amount of milage on stock equipment, you may want to consider the injectors to be clogged or getting clogged too.
You can try seafoam to clear possible clogs/debris in the motor area. That will also, possibly, clear/clean out your injectors if those are affecting your acceleration. If nothing at all, you've just cleaned out your throttle body/injectors/combustion chambers.
This just makes me think of your problems are fuel related, sorry.

Keep in mind too, that idle rpm acceleration is different than accelerating with a load on the motor. At least my car does.

I know you've stated that you don't have vacuum leaks but you may want to replace all your vacuum lines anyway. Like you stated above, you have 133xxx miles on your car. Oh and your BISS screw o-ring must be hard as a rock by now too.


...and here's a seafoam post... Seafoam works!

Hope that helps,
John

 

[bane3d]

Can I make a request of you? Please fill out your car's profile. I read this and was wondering if you are having an injector problem, fuel pump problem, or something unknown. I'm wondering if you have a gm maft setup or something that is giving you problems. I'm looking at it like this:

1. You either have too much air (doubt it) or not enough gas.
2. If it's not enough gas, then it's one of 3 reasons:
2a. System thinks it has less air than it really does
2b. System thinks it has more gas than it does
2c. System can't deliver enough gas.

So are we dealing with a bad 02 sensor, bad injectors, bad fuel pump, or bad maf/maft? Is there anything that I'm missing?

d

 

[blackrosenova40]

Everything is bone stock on the car

 

[blackrosenova40]

So I installed a Ari/Fuel Gauge........................ Useless