need knew ideas for what could be wrong

I have a 1986 305 caprice, bought it about 2 months ago it barley started and was running on 7 cylinders, since then i have changed the spark plugs, plug wires, oxygen sensor, air filter, fuel fillter, oil filter, oil, distributor cap, valve cover gaskets, changed the timing, and almost every other basic thing you can think of except the rotor (which didnt look to bad) But for some reason still have a pile of problems.

first it still missfires and when i put it in gear it jumps, also the check engine light will not go off. does any body know what might be wrong, if so let me know. please!!!!!!

i would also like to know how to use a papper clip to chek for codes in the computer.

How do I read my computer codes?

Tools needed:
Your car keys
A paper clip or a three(3) inch long piece of safety wire.

First thing you need to do is find your Assembly Line Diagnostic Link or ALDL. It s small black plastic piece about two (2) inches wide by one half(0.5) inch tall. It has twelve (12) female connector inside. The ALDL can be found under the driver's side of the dash, usually attached with two (2) screws to the bottom side of the dash.

The ALDL :

Now that you've found the ALDL, bend the paper clip or the piece of wire into a U shape. With the ignition in the OFF position. Insert one end into the A slot and one into the B slot. Now turn the the ignition to the ON position. DO NOT start the car. As the ECM begins it's self-test if will begin to flash the SES light to provide the codes. The flashes will appear like this : *flash* short pause *flash* *flash* long pause then repeat. Each code will be displayed three(3) times. Code 12 will be repeated to indicate the end of the set codes. If you all you get is Code 12 then you have no codes set in your ECM.

An example of a sequence for a common code :
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* *flash* *flash* short pause *flash* *flash* long pause = Code 32, EGR
*flash* *flash* *flash* short pause *flash* *flash* long pause = Code 32, EGR
*flash* *flash* *flash* short pause *flash* *flash* long pause = Code 32, EGR
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM
*flash* short pause *flash* *flash* long pause = Code 12, Testing the ECM


Clearing the codes is really quite easy. Unhook your battery for about 2-3 minutes and then hook it back up.

These codes cover the OBD-I computers only.....
All currently listed codes are from the 1989 B-car Service Manual. Why? Because that's what I have. If you have others that aren't listed or need to be added, just let me know.


CODE AND CIRCUIT POSSIBLE CAUSE

CODE 12 = System check
Indicates that the ECM is functioning.

CODE 12 = No Engine Speed Reference - VIN 'Y' CARB
Indicates an open or ground in the distributor reference circuit.

CODE 13 = OPEN Oxygen Sensor (O2)
Indicates that the oxygen sensor circuit circuit or sensor was open for one minute while off idle.

CODE 14 = Coolant Sensor (CTS)
Sets if the sensor or signal line are grounded for 3 seconds. HIGH Temperature indication.

CODE 15 = Coolant Sensor (CTS)
Sets if the sensor wires or connections are open for 3 seconds. LOW Temperature indication.

CODE 21 = Throttle Position Sensor (TPS)
TPS voltage of more than 2.5 volts for 3 seconds at an engine speed less than 1200 rpm. HIGH Voltage Signal.

CODE 22 = Throttle Position Sensor (TPS)
A shorted to ground or open signal circuit will set code in 3 seconds. LOW Voltage Signal.

CODE 23 = Manifold Air Temperature Sensor (MAT)
Sets if the sensor wires or connections are open for 3 seconds or Intake Air Temperature (IAT) LOW Temperature indication.

CODE 24 = Vehicle Speed Sensor (VSS)
No vehicle speed present during road/load deceleration. NO Vehicle Speed Indication.

CODE 25 = Manifold Air Temperature Sensor (MAT)
Sets if the sensor or signal line are grounded for 3 seconds. Or Intake Air Temperature (IAT)
HIGH Temperature indication.

CODE 32 = Exhaust Gas Recirculation (EGR)
OR Vacuum switch shorted to ground on start up. Switch not closed after the ECM has commanded EGR for a specified period of time OR EGR solenoid circuit open for a specified period of time.

CODE 33 = Manifold Absolute Pressure (MAP)
MAP sensor output too high for 5 seconds or an open circuit. LOW Vacuum.

CODE 34 = Manifold Absolute Pressure (MAP)
Low or no output from sensor with engine running. HIGH Vacuum.
CODE 35 = Idle Air Control (IAC)
IAC error.

CODE 42 = Electronic Spark Timing (EST)
ECM has seen an open or grounded EST or Bypass circuit.

CODE 43 = Electronic Spark Control (ESC)
Signal to the ECM has remained low for too long or the system has failed a functional check.

CODE 44 = LEAN Exhaust Indication
If voltage to oxygen sensor remains BELOW .2v for more than 20 seconds code is set.

CODE 45 = RICH Exhaust Indication
If voltage to oxygen sensor remains ABOVE .7v for more than 1 minute code is set.

CODE 51 = PROM - Faulty MEM-CAL or ECM.

CODE 52 = Faulty or missing CAL-PACK.

CODE 53 = System overvoltage
Indication of a faulty alternator or regulator. Camaro/Firebird uses a Code 53 for Vehicle Anti-Theft System (VATS).

CODE 54 = Low Voltage To Fuel Pump
Sets when the fuel pump voltage is less than 2 volts when reference pulses are being received.

CODE 55 = Faulty ECM

Damn CD,

I think that is the most comprehensive post that I've ever seen to cover code reading for OBD-1....

Would someone PLEASE sticky that at the top? There's always someone who needs to know how to do that.

I've asked and asked to get a sticky with this info in it but can't get it done. It's a file that I keep on the Files page of my yahoo group for 77-90 B-body owners. W worked it up when we used to be over at GMForums.com, before it went under.

I just post it when ever someone asks. I've posted it enough times that I would think a simple search could find it multiple times....

Here is a link to a site that goes along with what CD posted. It has a picture of the ALDL and shows the "A" and "B" slot locations for reference.http://www.geocities.com/dann8785/serviceenginesoon.html

thanks...:)

ok, i tried the papper clip thing and when i did it nothing happened, i put it in the slots showed by the diagram turned on the switch and got nothing but a ticking sound and it wasnt the fuel pump.
What does that mean?
oh yeah i looked at the diagram again and saw that the ports arent the same on my car, on my car port one is occupide then port two is empty then the rest are filled on the top and the whole bottom row is empty.
What do i do next?

Think you might not be there it's under steering wheel with about 12 wires hooked to it the openings are in your face looking at you

i know what it is and where it is, what i did just didnt work i'll take a picture of it or something and post it when i get time.

[EDIT] ok maybe i wont post a pic, (my comp. is under construction).
But its right under the steering wheel on the bottom of the dash to the left a little bit. it only has wires going to the top row and only five of them up there, why i dont know. Can somebody post a link to a real pic. of one,,,Thanx ;)

If the paper clip thing just does not work, spend the $25 or so to buy yourself a code reader from Autozone or Advanced Auto Parts. It plugs right up to the slot and comes complete with an instruction manual and code definitions. Yeah, you have to spend some money, but its not that much and takes all the hassle out of it.

that was the plan at first but i herd about the papper clip thing and was curious, thanks anyway.

(since i already have a thread open) Does anybody have any tricks or anything to ad a little horsepower to a small block 5.0 305 v8 besides the dual exhaust and cold intake, something like the ring and pinion gears or somethin with the drivetrain. thanks..