Alright I got my new engine in got about 120 miles on it, 350 cam,headers,holley tbi, manifold, and a 350 cop car chip! Anyways i think i have a timing problem first off i am using my harmonic balancer off of my 305 engine big no no i know! so the timing mark is off so i located top dead center by the keyway on the crank and put a screwdriver in the #1 cylinder, and from previous post i read that it about two inches to the left is were the timing mark should be. did that and installed my distributor by that, so i got a timing light and timed the ****, and from what i have read set it on 0 degrees with the est unplugged, did that the motor idled fine, so i give it some gas and i get a backfire so i turn the distirbutor counter-clock wise the and give it gas no back fire and and the motor runs strong so i put the light back on it to see where it is at the mark on the vd is way past the timing marks practically in the center of the timing cover i unplugg the est wire and it does nothing the timing stays where it is! Now where the timing is now(probably like 20*) the motor pulls real good no back fire but when i am idiling at a light the rpms stay at about 1200rpms and slowey comes down after like 30 seconds and then the idle bounces around and feels like the motor is missing, so do u guys and girls if there are any in here think that i am off by like a tooth on the cam, i have adjusted my valves per the cylinder 1/2 past ....So are there any recommendations as to what i should do.Should i have installed the distributor by the keyway on the crank? and why am i getting a backfire when i set it to 0 degrees for the timing i am really stumped

 

Come on now did i really stump you on this question,am i really the only one who has un-heard of problems??

 

After you time it with the EST disconnected you have to shut off the engine for a minimum of 10 seconds, reconnect the EST, then restart the engine.

With the EST open (actually the EST bypass line) the ECM will lock in the code 42 malfunction until the ECM is power cycled. With the code 42 malfunction locked in the ECM will not control the timing.

RBob.

 

i'm having a similar problem, have yet to solve it, but i can help on the "tooth off" issue.

I'd always heard you installed the distributor with the rotor facing the number one cylinder. that's incorrect. there are 13 teeth on the distributor gear, so there are 14 possible positions in which you can install the distributor. the engine will run correctly in any of those 14 positions AS LONG AS the rotor is pointed at the #1 plug wire terminal on the distributor cap. trust me, i argued over this one and got seriously flamed in the general engine board. finally, we checked it on a friend's car and found it to be true.

i don't believe your problem is in where the distributor is installed.

on my car, the engine ran perfectly, i parked it, got back in several hours later and it had no fire. plenty of gas, but no spark.

coil checked out fine

replaced ignition module ... no fire

replaced distributor ... ran, but terribly. had to advance timing off the scale just to get it to run. surmised distributor was "one tooth off"

pulled #1 plug, rotated engine till end of compression stroke and piston at tdc. timing mark was on "0" reinstalled distributor. still ran terribly.

repeated process more times than i care to remember. moved distributor forward and backward in every possible position. no help.

pulled front cover and checked timing chain. engine was in time. chain was a little slack, so replaced anyway. no help.

car runs, but only with timing way advanced. i'm sure it's not just out of time. it spark rattles and make white smoke, it's obvious that the timing is too far advanced, but it will not run when timing is turned back.

am at wits end.

right now we're trying to figure out if it's a problem with the msd unit. the car runs with it plugged in, but won't if it's bypassed. according to the installation instructions, it should run.

anyone have any ideas?

 

MY car does not run rich or ne thing like that ,but tongiht i am going to pull the timing cover make sure i am on the compression strock and mark my vd so i actually no i am on true tdc, the engine runs smooth at idle when it is on 0* like it should be, but when i give it gas back fires out the exhaust then i advance it to run right and the motor idles like crap , so i am just going to try and see if i am off tdc......plus like i said i will feel more confident that i am on true tdc......i will post to update yea on the info, if it is not that then i will next suspect my egr valve is leaking i am probably going to pull it and put a block off plate on it, ow well if it throws a code.////

 

don't make the same mistake i did. if you get to tdc and the timing mark is on 0, your timing has not slipped.

the piston comes to the top twice on a 4-stroke engine. you want it to be at the top immediately after the compression stroke.

take # 1 pulg out

rotate the engine manually with your finger over the #1 spark plug hole.

when you feel air pushing against your finger, you're on the compression stroke. both valves are closed.

carefully put a long screwdriver into the #1 cylinder

slowly rotate the engine till the piston is at the top.

check the timing mark on the harmonic balancer. if it's at 0, your engine is in time.

if you really need to make sure, pull the valve cover. when the engine is at tdc and you continue to rotate it, the exhaust valve will begin to open. if the intake valve begins to open, you're on the wrong stroke.