A little back story first. This is my fourth F-Body. Priors include: 1986 Camaro Coupe (V6), 1987 Z28 (305 4bbl), 1995 T/A. I love these cars. I am now the fifth or sixth owner of a 1986 LB9 IROC-Z 305 TPI Auto. Not sure on the exact specs of the transmission. I've worked on cars a little, done a lot of brake jobs, oil changes and plugs and wire. Nothing more major then changing a master cylinder, and nothing involving a multi-meter, so I haven't ventured there for solutions yet.

I bought the car from a friend of a friend for $1500.00. He bought it from a co-worker and when he got it, the engine was in pieces. He put the engine back together, put a new water pump on it, all new belts and hoses a new MAF and air filters and got the thing running. From there, it sat in his back yard for a few months until I scooped it up from him.

First off, the car runs. I drive it daily. But, it's tempermental. It takes a second for it to start, and fires up kind of rough. Once it's running, I have to keep my foot on the gas to keep it from stalling out. After its warmed up a bit, I can gently remove my foot from the gas and can usually let it idle. When it's hot outside (100 degree+), it idles around 500-600 RPM and dies very easily if I try to move it. Once I get out of my complex and on the road for a 1/4 mile or so, it usually won't stall out again. When I come home from work and it's around 80 degrees it idles closer to 700-750 RPM.

I've replaced the rotor, plugs, wires and fuel filter so far. I'll be replacing the distributer, ignition coil and O2 sensor next. Should I look into replacing the TPS and the IAC? Does any of this sound like those are going bad?

When I'm driving, I can hear kind of a fluttering coming from the engine, almost a chirping. I've also noticed that the injectors seem to be somewhat noisy. Is this a sign of the injectors going out or perhaps not getting enough fuel? Are the injectors easy to change? Once I get the chance I'll check the fuel pressure, just to try and rule that out.

I can also hear a whine coming from the rear of the car, which I'm pretty sure is the fuel pump. It's been less noticeable since I've replaced the fuel filter and filled the car with gas, perhaps the pump is going bad or should I be able to hear it? I kind of want to replace the pump and sending unit anyways.

I replaced the rotor, and would have replaced the distributer but the genious at Checker gave me the wrong one. There were three sets of wires going into the distributer. Two of which hooked up towards the end of the distributer where it said "Tach" for one and "Bat" for the other. In my eagerness to work on the car, I disconnected those two wires without noting where they were installed. Now, my tach seems to work fine, and when its hot out, my voltage gauge for the battery seems fine too. But at night, when its cooler, the voltage seems to be kind of odd. While the car is idling, the voltage will drop all the way into the red and the dash lights will dim slighty. When I start moving, the voltage will come up a bit, not quite into the 12volt range, and the dash lights will come back up to full brightness. Now, does it sound like I hooked up the wires backwards? Is that even possible and would switching them potentially cause any kind of damage?

Finally, when at low RPMS when my lights are on, if I turn on my blinker, the RPM gauge will tick about 100rpms in sync with the blinker.

Any help on any of these issues would be greatly appreciated. I know this car has a ton of potential, and I want her to run her best. I don't have much discretionary income, but am willing to invest what I can to bring out its full potential.

Thanks in advance!

 

The dim lights at idle is def an alternator issue. They get hot with the extra load and don't put as much out at idle... give them some RPM and it starts to work again.

IT could probabaly use a rebuild kit. I always like rebuilding my own alternators because it's much cheaper... and there really isn't much to them.


The whine at the back of the car is semi normal. Mine does it, and most of them do. If you are concerned about the pump, throw a fuel pressure gauge on it. should be ~40PSI

For the injectors, test the impedance of each one. It should be over 14 ohms optimally. Anything lower then 12 should be replaced.


Good luck!

 

first off I think you are missing out on the home page

check out the tech data and technical articals

I could retype it but why

you need to set your Iac and your tps

when you get to the tps I have a short cut

find the lead from the computer and check it from there

 

I think I'll just replace the IAC and the TPS for good measure. At least it'll be something I won't have to think about for a while, and they both seem relatively easy installs and aren't expensive. As far as the home page and the tech articles, I've been scanning through them fairly frequently. It was through these, and message board posts, that brought my attention to the TPS and IAC in the first place.

Anyone else have any ideas? Thanks!