Performance Issues

hey everyone, i have an 89 caprice, 305 fuel injected with 127K miles on it. in the mornings when running the car, it runs with no problems. only in mid-day and after it has ran for a while it's would begin to hesitate and eventually die. needless to say this would take place at anytime, in some cases i would have to drive with both feet in order to get where i was headed. in my attempt to remedy the problem i have had the ignition module replace, fuel filter and fuel pump replace, muffler is about 2 years old, catalytic converter is clear. ignition coil checked out. I'm all out possibilites as to what it would be. i've been told it maybe the ignition coil shorting out or pick up coil or 02 sensor. if anyone has had this problem and found out how to remedy this problem. please hit me back. all ideas and recommendations are appreciated. thanks. :)

i just used a jumper to get the code and it gave
12,23,42,43

hopes this helps

Code 12 is just a code telling you the diagnostic terminal is grounded out, and the diagnostic codes will be displayed. I'm not sure what code 23 is on your car. On a carbureted car its the mixture control solenoid, so it could possibly be something to do with fuel on your car. Code 42 is an issue with the spark timing control. Odds are its a malfunctioning HEI module. Code 43 is the electronic spark control unit (ESC). This is caused by the ESC retard signal being on for too long, or the system failed the computer's function check.

So it looks like its the electric module thats on the distrubutor, mounted underneith the distributor cap. Its a black computer chip-looking thing, sometimes labeled. Theres a few plugs coming out of it.

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

isnt that electic module you're talkin bout the same as the ignition module? whatever the case it'll come off tomorrow and get tested. i'll keep you guys posted. thanks.

well went to auto store to have the electric module tested. they ran the test 10 times and it past all 10 times. the guy did advise me that sometimes if it test ok, it could still be bad. he said on his car he tested his module and it test fine but when he replaced it fired right up without a problem since. any ever heard of that before? and if not also check the coil which tested fine. any other ideas?

well..tried replacing the ignition module and i'm still having the sample problem. havent checked the codes again yet. anyone have any other recommendations?

You know it sounds to me like your knock sensor is failing...

Read this, I know it's about Astro vans but it seems relevent to me.

http://www.obdii.com/ubb/Forum1/HTML/001357.html

aiight i'll give that a try. i understand that it's located on the block in front of the starter. is replacing the knock sensor something that can be accomplished myself, or requires some specialty tools or procedure to accomplish. i'm just asking before i go out and buy one if it's best i have a shope replace it.

okay.

replaced knock senor, started it..ran great. let it run for a few minute. took it for a drive. probly got a mile at best and it cut out on me again as it has been doin, check engine light on and everything. get the car back home, use the jumper again, still get the same codes 42 and 43. i'm really clueless as to what's goin on. what else should i try. replacing distributor cap? what's next?

i've also heard that it can be ignition pick up, i beleive that's what it's called. it's located under the distributor cap, it plug into the ignition module but it's from within the distributor cap. could that possibly be it? i've also heard that the push rods might be clogged and that could be the problem. other thing i notice it when i took the knock sensor off it leaked antifreeze from the whole, is that something to be concerned about?

here's something i notice. i started to the car in park tryin to see if i see any movement from the egr valve (the lil pin or whatever you call it) while the car is running, i dont notice any movement however the car quits...after the car quits i'm hearing a series of "clicks" that sound like it's coming from the throttle body and the inside of vapor canister it sounded as if something was bubbling on the inside of it. hook up the jumper to get the error codes. i got 23, 42 and 43 again...so i place the bottom of the air filter back one and plug in that air sensor and started the car again..after a couple minutes..it died again..still doin the same clicking noise and bubbling noise from the vapor canister. check the codes again..still got 42 and 43. what could those noise be indicating?

here's another addition to the mystery, when the runs in park (as well
as when in traffics) there's a noise, something like a rattle but more
like a moving part that's not lubricated ( ball bearing is what comes
to mind) but when i disconnect the est (brown wire with black stripe)
that noise goes away. is that an indication of anything?

also tested the EGR. started car this morning let it run idle for a few minutes. pushed in the diaphram and the car began to run rough and just about quit. after i let it go and ran smooth and began to idle up again.