SERIOUS issues....
dk05
09-21-2005, 03:05 AM
OK, I have no idea what could be wrong with my car. It is a 1985 IROC-Z with the 5.0 H.O. TPI. First off, it is randomly starting hard, then all the lights/guages flicker all crazy and jump around and the car misfires alot while it is doing it. Every time it misfires the lights dim or go out completely. Then there is a random loss of power/hesitation/bogging down, and the car sounds like a wet fart (sorry, no better description) when you try and accelerate. Also when I let off the gas the car jumps back hard, then when I step on it again it jumps forward hard. Then I also noticed there is a random loss of exhaust sound.... it's really odd cause the car normally is very noisy when it runs because of the headers on it. The car also randomly chokes off, sometimes while moving other times when I put it in gear and every now and then right after I start it. I know this is alot of info, but I wanted to be as detailed as I could. Seriously, any kind of info/suggestions you can give me (asside from junking the car, lol) would be greatly appreciated. Thanks.
ct91rs
09-21-2005, 11:11 AM
Given the randomness and multitude of problems, it sounds to me like an interruption in power/ground. I'd start by checking the battery cables for corrosion. The battery to engine block ground, and the grounds on the back of the motor (just behind the valve covers) on either side.
DaMoNe6969
09-22-2005, 01:02 AM
Just like CT said, check all your power/ground cables.. Ide also check all the plug wires for any spots that may be burnt or rubbed through.. and the cap and rotor for cracks, etc.
If they're old, replace them anyway..
If they're old, replace them anyway..
dk05
09-22-2005, 01:23 AM
Thanks for the replies. I was also thinking something electrical was the problem. Haven't checked the plug wires/distributor yet, but I did clean all the connections on the battery and the vehicle and alternator grounds. I had the alt tested and it was way above normal so that must not be the problem, also I replaced the belt on the alt and the bolt going into it because it was stripped out and not holding the alt to the correct tightness causing it to slip and squeal (which is the reason I actually replaced the belt in the first place). When I had the alt out I put the battery on a 12 hr charger also to make sure that was all good. I will try and post again after I check the plug wires and distributor. Hopefully I can figure out what the prob is because I really don't want to get rid of the car. Oh yeah, and does anyone know if this car is supposed to howl from the rear end when when you hit the gas pedal? I think it's either the fuel pump or the rear axle making the noise. Leaning toward the FP though because it only happens when I touch the gas. Can't really notice it when I get on it hard though cause the engine makes too much noise normally when it is running good. Thanks again for all the help.
ct91rs
09-22-2005, 09:50 AM
Oh yeah, and does anyone know if this car is supposed to howl from the rear end when when you hit the gas pedal? I think it's either the fuel pump or the rear axle making the noise. Leaning toward the FP though because it only happens when I touch the gas. Can't really notice it when I get on it hard though cause the engine makes too much noise normally when it is running good. Thanks again for all the help.
I believe the fuel pump makes a constant sound that doesn't vary with engine rpm (i.e. pump does not increase or decrease in speed, it's either on or off, but I may be wrong). Does it happen when the car is in neutral? If it does, then in's not a problem with the rear. If it doesn't make the howl in neutral, than I'd look for a bad wheel bearing or U-joint, possibly a bad carrier or pinion bearing, but that's not as likely.
I believe the fuel pump makes a constant sound that doesn't vary with engine rpm (i.e. pump does not increase or decrease in speed, it's either on or off, but I may be wrong). Does it happen when the car is in neutral? If it does, then in's not a problem with the rear. If it doesn't make the howl in neutral, than I'd look for a bad wheel bearing or U-joint, possibly a bad carrier or pinion bearing, but that's not as likely.
dk05
09-23-2005, 09:10 PM
OK, I replaced all the plug wires, and the distributor looks all good. Here is what I did notice though. There seems to be some sort of ticking noise that sounds like an arcing from under the car like right behind the front driver side tire and also a smell like burning plastic from the inside upper wheel well of the same wheel. No idea what this could be. I also found a broken vacuum hose under the TB and repaired that also. I did notice that the "short" in the electrical system seems to only happen or at least happens more often when I have all the accessories on, but it only happens when I put my foot on the gas. All I can say is I am seriously stumped. I hate to even try and drive the car because it keeps choking off on me while I am driving it. Thanks again for the help.
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