just a quick question can the rotor be pointed to the left or right of this picture? httTp://s11.photobucket.com/albums/a187/swartlkk/2000%20Bravada/distributor_align2.gif
which way would advanced be?
Thanks

 

Should be right on the alignment mark.

The rotor spins clockwise so you would be advancing the timing if you were to the right of the mark and retarding it if you were to the left.

 

I put an ad on craigslist for anyone with a scan tool with diagnostic capabilities lol and amazingly had replies..anyways i met up with a guy scanned it and read sensors and everything fuel etc..everything checked out ok except the timing was jumping all over the place...checked timing marks and all lines up exact! called his buddy who is a master gm ase certified mechanic he said anytime the distributer is pulled it has to be re-synched..the scan tool we had was not capable of doing this..ummm i thought it had to be synched only if the crank and cam sensors were replaced?

 

Never heard that before. I know it is required whenever the CMP or CKP are replaced because the purpose of the CKP/CMP Correlation value is to correct for manufacturing tolerances on these two sensors and the rest of the system. But if nothing has been replaced, you should not need to relearn this value.

 

While this is usually the case for most instances, something that I don't believe has been considered is the fact that this is a replacement engine in this truck. That being the case, if the computer in the truck is the original to the truck and not the one that belongs to the engine that was put into the vehicle. Then these stored values would indeed be incorrect and need to be relearned since as far as the computer is concerned those sensors HAVE been replaced.

 

Definitely, if the motor was replaced and a CASE relearn not performed, then it must be done. As I said, if the CMP or CKP sensors are replaced, or any other component in the system (the components that link cylinder compression timing to distributor timing - crank, timing set, cam, distributor gear, and/or the complete distributor), a CASE relearn is required. Just did not read back to the top to see that the engine was replaced...

 

Today i had the Blazer in the shop they performed ignition tests and everything passed spark plugs wires cap rotor & coil all fine even a noid test all ok..checked compression and did cylinder leak down all passed with flying colors..they even tested the fuel system and all tests passed. they told me it may be the spider unit may be bad (poppet #4)...well i went and got a Brand new one today under warranty and installed it. Guess what! Still P0304 misfire lol.. so i did some research and my new buddy
(who had the scan tool) found a service bulletin specifically for the 1995 4.3L Vin code W ...The crank sensor if not installed correctly and torqued correctly will result in a p0300 code OR an individual p0301 to p0306 cylinder misfire. i Guess I learn something new everyday lol.. gonna buy a new crank sensor if you guys think its worth a try...anyways the dealers around here are idiots because they told me i dont need to have it relearned or synched..Thanks Kyle for the info above...now all i need to do is find someone to do this that KNOWS what they are doing lol..(any idea how much a relearn costs)? I can't wait to find the root of this problem!! I hope who ever is following this Thread gets some use of it lol..
ThankYou everybody for the support..

 

Found this post do you think it will work?

Re: How do I reset my computer?
Yeah, at least 10 minutes. If you'd like to speed up the learning process, you can take it through a complete driving cycle.

Cold Start. In order to be classified as a cold start the engine coolant temperature must be below 122°F (50°C) and within 11°F (6°C) of the ambient air temperature at startup. Do not leave the key on prior to the cold start or the heated oxygen sensor diagnostic may not run.

Idle. The engine must be run for two and a half minutes with the air conditioner on and rear defroster on. The more electrical load you can apply the better. This will test the O2 heater, Passive Air, Purge "No Flow", Misfire and if closed loop is achieved, Fuel Trim.

Accelerate. Turn off the air conditioner and all the other loads and apply half throttle until 55mph (88km/hr) is reached. During this time the Misfire, Fuel Trim, and Purge Flow diagnostics will be performed.

Hold Steady Speed. Hold a steady speed of 55mph (88km/hr) for 3 minutes. During this time the O2 response, air Intrusive, EGR, Purge, Misfire, and Fuel Trim diagnostics will be performed.

Decelerate. Let off the accelerator pedal. Do not shift, touch the brake or clutch. It is important to let the vehicle coast along gradually slowing down to 20 mph (32km/hr). During this time the EGR, Purge and Fuel Trim diagnostics will be performed.

Accelerate. Accelerate at 3/4 throttle until 55-60mph (88-96 km/hr). This will perform the same diagnostics as in step 3.

Hold Steady Speed. Hold a steady speed of 55mph (88km/hr) for five minutes. During this time, in addition to the diagnostics performed in step 4, the catalyst monitor diagnostics will be performed. If the catalyst is marginal or the battery has been disconnected, it may take 5 complete driving cycles to determine the state of the catalyst.

Decelerate. This will perform the same diagnostics as in step 5. Again, don't press the clutch or brakes or shift gears.

 

I still have the annoying P0304 code! I called 3 different GM dealerships and asked about having the computer reflashed each one said i don't need to, even after explaining everything i have done. I called my repair shop and told them that changing the Injector unit didn't change anything and the service manager wants me to bring it back in for more testing FREE of charge... Cant beat that lol so i will post any results when i find something out.
Could the knock sensor cause this? its right above the #4 spark plug

 

I doubt the knock sensor is causing this problem, but someone that knows what they are doing with the proper scan tool can know for sure.

And flashing your computer is different than doing a CASE relearn.