16 yr old in need of help with motor

[16yroldguy]

Hey, whats up?...im a 16 yr old guy from texas...i have a 89 chevy long wheel base reg cab, with a 350 and a 700r4 (I believe) automatic transmission...
ok
what my problem is....is that in the mornings it takes forever to start...i have drained the battery a few times trying to get it to start, and when you finally do get it started...it is always back firing and popping...and running real rough..your lucky if you can do 65-70......down hill! and its always dieing...and if you kill it after driving it 10 miles..you will never get it started again untill it cools off and you drain the battery...well...i have been told that the timing was off..and i have also been told that the timing chain could be worn..or the cam..but it is almost a new motor..only like a year old...i dont know what to do..i have been told that if i put a performace chip in it...it will reset the timing..cause the computer controls the timing..does anyone know if that will work...and if so..where will i be able to get a chip..how much...and what will it take to put in..any help would be greatly appreciated..thank you very much
David

[tidalcock]

have you checked the fuel filter? Does your truck have a carburetor or fuel injection? Does it have electronic ignition or a distributor? More information may be helpful.

You may have a serious problem with the timing chain, but do't overlook simple things like fuel filters, spark plug wires, distributor caps, points, etc.

Good Luck!

[16yroldguy]

hey, i have changed the fuel filter, and my dad bought a little thing that is a decoder or something...it is throwing a code 12, 14, and a 43...
12-Diagnostic mode;no distributor signal to Electronic Control Module;System PASS
14-Coolant sensor or circut fault - signal voltage low or shorted
43-Electronic spark timing (EST) circuit - low voltage detected----Electronic spark contorl (ESC) - circuit problems
it has a throtel body fuel injection, we have replaced the fuel filter, the distrubiter cap, the ECM, plugs, wires. i dont know what else to do...so please help. if you need anything else just let me know and i will try to get it...sorry i forgot to put that information on there...

[tidalcock]

Sounds like you have several possibilities. That stuff is way over my head. You may want to take it to Autozone - they can possibly analyze the engines and codes for free. If you don't want to take it to a dealer, you might try some place like Precision Tune. Sorry I can't be of more help. See if you can get GM Merlin to help you. He is very knowledgeable.

[tidalcock]

GM Merlin posts on mychevytruck.com. Post your problem over there and try to get his attention. Best of luck. Hope you get it figured out soon!

[99ssconv]

the code 12 is normal, don't worry about that one, the code 14 is the one that is causing your problem, the coolant sensor tells the computer the engine temperature, if the computer sees the wrong temp, lets say its seeing that the engine is -40 degrees then the computer will pulse the injectors with a ton of fuel thinking it needs it when it really doesn't. without a scan tool to actually read the temperature you can do this. the sensor is mounted on the front of the intake manifold, it has a black and a yellow wire. disconnect the sensor, inspect for corrosion or terminal damage, next measure the black and yellow wires with a voltmeter, key on engine off you should see close to 5 volts across the circuit, if this is good then you probably have a bad coolant sensor. good luck. I wouldn't worry about the code 43 until you get this going.

[16yroldguy]

thanks for all the help...i just got in from a fire call..and as soon as i wake up im going to check the collant senser...and im going to post at my chevy truck right now..thanks for all the help.......

[16yroldguy]

hey, i checked out the sensor, it was right about 5...and no corrosion or anything...so what do i do next...i have heard if i put a different chip in it...that it will reset the timing..or is there any way i can change the timing...or should i just buy a new computer..a friend of mine wrecked his truck..and he said i could have his computer..do you think that replacing the computer would fix it?

[covvy]

If you are certain that your firing order is correct and that the state of tune is good then look towards possibly an intake leak or defective MAP sensor. Check for an intake leak by spraying carb clean around the inkake manifold, with the air cleaner installed to avoid a possible false signal, and watch for the idle to smoothen out or pickup. If either happens then there is a leak in that location. If you think it may be the MAP sensor then unhook it and try to start the truck. If it starts better then before then probably its faulty. Starting the truck with it unhooked sets the computer to a base map based upon engine RPM. How far off is your timing? From the backfiring it sounds like you've got a few plugs out of order but I may be wrong. When you said you replaced the ECM (electronic control module) did you mean PCM(powertrain control module) and if not which ECM did you replace? Terminology is a pain. Good Luck.