still wont start

put new sender unit fuel pump, set # 1 tdc and rotor to # 1 in the cap. backfierd thu the tbi, took oil filer cap off and smoke came out. could it be egr? or could i have distributor out?

Was the distributor out? If so, when you aligned the rotor to #1 and with the engine at TDC, did you verify the engine was on the compression stroke? It sounds like your distributor maybe off 180 degrees. If the distributor was just reinstalled and you didn't make sure it was on compression stroke, there's a good chance you can solve your problem by getting the engine back to TDC with the rotor rotated 180 from #1. Then pull the distributor and reinstall it pointing at #1. Better still check to make sure it's on TDC compression stroke when the rotor is at #1. I'm not sure how to check whether it's on exaust or compression stroke other than by pulling a valve cover and looking at the valves, maybe somebody here knows another way.

Good luck.

Also when being timed, the ECM has to be disconnected from the distributor..Firing order is 165432

Sounds like your 180 out also do you have the cross fire cap ?? if so make sure your on number 1

Sounds like your 180 out also do you have the cross fire cap ?? if so make sure your on number 1
i tryed to start it and it blew the corners of the valve covers up an inch. so i removed the valve covers and there is no carbon of any kind.the man at the parts store said it must be carboned up prety bad for it to back fire. this truck was runing excelent no pings or knocks, or misses. it just satarted runing out of gas. i put 5 galons in it to be sure i had gas and when i tryed to start it it back fired thru the exhust,and black smok and kept backfireing . i replaced entire dist, coil wires cap timing chain. i need to time it with a lite but i cant find the wire to unhook. this is a tbi couldnt i just remove the 2 plugs from the dist.could the tbi be geting to much fuel how would i check. it. the egr seems to be working. what else could it be. thanks

It would have been helpful to keep all this in one thread:

http://www.automotiveforums.com/vbulletin/showthread.php?t=401806

http://www.automotiveforums.com/vbulletin/showthread.php?t=405918

Carbon cause a backfire no
Backing fireing is caused by the wrong ign timing or a very lean fuel problem, worn cam ,broken valve spring just to name a few things.
If this problem just started out of the blue and you had al ready replaced the timing chain recheck that you are on number 1 cylinder compression stroke at top dead center and pull the dist cap and see where the rotor is pointing.

Carbon cause a backfire no
Backing fireing is caused by the wrong ign timing or a very lean fuel problem, worn cam ,broken valve spring just to name a few things.
If this problem just started out of the blue and you had al ready replaced the timing chain recheck that you are on number 1 cylinder compression stroke at top dead center and pull the dist cap and see where the rotor is pointing.
fireplug do you think my engine is junk because of all the backfireing?I have the #1 piston on tdc... I try and line the rotor with # 1 in the cap. on that plug wire in the cap is going to # 1 spark plug.. i think if anything i am not geting the distriburtor i right .. i have # 1 wire in the cap from the hold down screw in the cap its the 3 rd terminal. i have rotor pointing to this terminal.then in a clock wise motion #6 ,#5#4,#3#2. when i start it it backfies and the tbi caches a fire.. could it be in the tbi.. i would like to time it with a light i do have a timing light, but i cant find the so called wire from the computor to unhook.. the man at the parts store said the timing for this truck is on the radiator shroud. i dont see nothing..... what i need to know is hou to hook this timing light up and where the wire is i unplug.. and what the timing sets on this engine... thanks..

Recheck your firing order, how did to align the dots on the cam and carnk sprockets, do you have a manual if so does it show where to put the marks.
What engine do you have?? does it run at all if it does run then slowly turn the dist (with the engine running) and see if the rpms pick up . try both ways untill you find the spot where the engine idles best.

Recheck your firing order, how did to align the dots on the cam and carnk sprockets, do you have a manual if so does it show where to put the marks.
What engine do you have?? does it run at all if it does run then slowly turn the dist (with the engine running) and see if the rpms pick up . try both ways untill you find the spot where the engine idles best.

yeah, the firing order he read off from his cap doesnt sound right. they do not go in that order. if you had a 2.8 that would be right but your #1 would be at 7oclock position.

fireplug do you think my engine is junk because of all the backfireing?I have the #1 piston on tdc... I try and line the rotor with # 1 in the cap. on that plug wire in the cap is going to # 1 spark plug.. i think if anything i am not geting the distriburtor i right .. i have # 1 wire in the cap from the hold down screw in the cap its the 3 rd terminal. i have rotor pointing to this terminal.then in a clock wise motion #6 ,#5#4,#3#2. when i start it it backfies and the tbi caches a fire.. could it be in the tbi.. i would like to time it with a light i do have a timing light, but i cant find the so called wire from the computor to unhook.. the man at the parts store said the timing for this truck is on the radiator shroud. i dont see nothing..... what i need to know is hou to hook this timing light up and where the wire is i unplug.. and what the timing sets on this engine... thanks..

You #1 plug on the cap is at the 5 o'clock position. the rest will be 65432 clockwise. That said, the ecm disconnect wire is behind the passenger side carpet coming out of the firewall grommet. It's a tan wire with a spade connector. Disconnect it before timing it. When setting TDC make sure you are on the COMPRESSION stroke, NOT the exaust stroke.. For the timing light, clamp the #1 wire and ground the ground wire at the bat, shine it against the timing mark on the timing chain cover.

you have a 93 4.3, so the firing order is 1,6,5,4,3,2 with #1 at 5oclock position. cylinder # front to rear, drivers side are 1,3,5. pass. side is 2,4,6.firing clock wise on distributor, #1 at 5oclock position than 6 then 5 then 4 then 3 then 2 then all should be well there. then make sure #1 piston is all the way up, when it is take cap off( leave plug wires attacched) make sure rotor is pointing to #1 or at 5oclockposition. then youre good there. use the manual to the timing light to use it. the wire youre looking for is in the cap behind or under glove box, it is brown. no you cant just unhook both connectors from distributor. time the truck. and if it still doesnt start please dont start a new thread about it.

He has a half ton pick-up. Will the timing wire be in the same place?

http://www.image-hosting.ws/direct/1361.jpg

He has a half ton pick-up. Will the timing wire be in the same place?

http://www.image-hosting.ws/direct/1361.jpg
jackass was right i had the rotor pointing at the 7 oclock position... heres what i did.. took # 1 spark plug out turned the engine untill i felt air expell from hole.. put a pencile in the hole and felt that piston was up . was up.. put distributor in and looking at distributor from the front of engine put rotor at 5 oclock.. put cap on with # 1 wire in line with the rotor.. turned engine a few times and double checked.. in a clockwise motion looking at the dist. put#6 wire next to # 1 wire then wire 5,432... now on the engine from left bank 246wires.. right bank drivers side 135.. iremoved the carpet and there was no wire, i do see a big harness of wire up behind the glove box, i will remove the glove box later.. after i take a brake and eat i will try and start the truck.. i do have a chilton manual, but it dont say where the wire is.. i do have a timing light and i know how to use it. i have worked on 318 and 305 engins way back but all this computor and emision stuff confuses me. if i cant get it runing this time i will leave it set,untill i get money to tow it into town and pay a mechanic.. thanks all you guys for your help.. ken

sorry i thought you had an s10. the wire to the tcm might not be same place or color.

sorry i thought you had an s10. the wire to the tcm might not be same place or color.
jackass.. had engine runing breifly with out back fireing, was missing bad so time is still off, still cant find the wire to unhook. on the timing cover the pointer had three points on it i cant see any lines or before or after marks.. i am going to try and set the vibration damper line to the midle point and that should be right on tdc, and i will make sure rotor is at 5oclock and #1 wire is right over rotor,, this truck run , so i know i am close if i can get it runing so i can get out and turn the distibutor i will put it on the money by ear..

yeah lining up the rotor to the right plug is just in ballpark, it still needs timed and fine tuned. glad to hear there is progress. good luck.

yeah lining up the rotor to the right plug is just in ballpark, it still needs timed and fine tuned. glad to hear there is progress. good luck.
jackass.. could the cam be bad? i had a couple 305 did this, but they at least run.. i am going to find the wire so i can put a light on it.. there no sticker on the shroud that tell me what the timing sets at.. the chilton book refers to the sticker. my sons 91 sets at tdc//

jackass.. could the cam be bad? i had a couple 305 did this, but they at least run.. i am going to find the wire so i can put a light on it.. there no sticker on the shroud that tell me what the timing sets at.. the chilton book refers to the sticker. my sons 91 sets at tdc//
got the old truck runing... i kept grting out and turning the distibutor a hair and it took off enough i could keep it runing and turn the dist.. check engine light came on for a while, then went off.. oil pressure is good... drove around the farm in it and has a slight miss.. starts up everytime.. i called the shop in town and they want 100 bucks to time it..if i bring it in.. they wouldnt tell me what the timing sets at.. do you know? one guy said the wire should be coming out of the harness by the dist.. ill keep looking for the wire..

if is a s10, it should be set 0deg(tdc). the wire ispluged into the computer. all it is is the spark advance. on the s10 it is brown.
glad you got it going.

Yep, 0 degrees TDC and here is a pic of the wire...Passenger side firewall

http://img.s10forum.com/album2091/aab.sized.jpg

good pic. that should help you out greatly. good luck.

dont forget when you set timming, and hook it (the wire) back togther, unhook your battery for a few min. to zero out your computer. when you unhook it your check engine light will come on(normal).

dont forget when you set timming, and hook it (the wire) back togther, unhook your battery for a few min. to zero out your computer. when you unhook it your check engine light will come on(normal).
thanks guys.. i didnt do any thing to day,got kind of a chest cold so i stayed inside.. i will find that wire tommorrow and time this truck, at 0.. my truck is full size work truck, but i think all the 4.3 are about the same.. yea the old truck sounds good except for a slight miss,, no valves noise or rod noise as soon as i time it i will change the oil.. thanks

how is everything? have you had a chance to mess with it? hope youre feeling better.

how is everything? have you had a chance to mess with it? hope youre feeling better.
jackass.. thanks for the reply, i have been down with pneumonia,everything better now as soon as i feel up to it i will try and get the truck runing, i borrowd a car so i can get back and forth to town.i found the wire that i am to unhook to time it. it in the engine compartment by the fire wall close to the distributor, this is a full size pick up.before i got sick i had it running with the valve coner off and oxgen sensor out of the exaust and it run good all over the farm and up the road no problems. then i put the cover on and the sensor in and now it wont start,, i think its a cam.