TBI to Carb...

[Cricket]

So to date you've checked the following: Problem no fuel from injectors.

1. I have replaced my ignition module.
2. tried a new working TBI
3. computer diag. the computer is getting power all codes are working properly.
4. swaped out my computer for my bro's working computer.
5. no cuts in the wires anywhere.
6. fuel pumping to the back of the carb.
7. i've checked the fuses and the ground at the tstat.
8. replaced pick-up coil.

 

[stockk5]

yes and no.... see i replaced the igniton module with one from a friends... not positive if it was good or not, wasnt in a truck when i tested it w/ my bros computer., i bought a new module, and a new coil, put both of them in, and it still doesnt run. the power is getting to the computer, and im not sure about the codes, i didnt personally check them. So tmrow i am getting my bros computer again and trying that again. Ill really need some help cuz my dads hell bent on on putting a carb on it after trmow if the computer doesnt work.

Basically i am starting from square one again with my check list now that i have a new module, and coil cuz i wasnt sure b4 on them. But few things i know for sure.. fuel to carb, fuses are good and grounds on the firewall/wire harness/tstat are all good and properly grounded. Thanks for trying to help. I am gonna prob go to the dealer if i cant figure it out... i def. dont wanna swap to carb, so much work and stuff, not worth it for me. i'd rather pay someone to make it work than spend all the money on a full carb set up.

 

[Cricket]

Carbs are no good off-road on any serious angles IMO. Some guys are very successful running them but not many. Just get the TBI fixed, Your looking at maybe one or two hundred to get it diagnosed and repaired. A carb will cost you more than that by itself.

 

[stockk5]

well we put the new computer in it today... didnt work... so i guess the injectors are getting power.. just no pulse... and really? a few hundred to fix it? i was thinking like 600 at least.

 

[Col_Sanders]

Mine did similar and it was the wires going from the coil to the ignition module.

My buddy said it did the same thing to him after he put the motor in and it was the battery cables. For some reason everything would work but the fuel pump. He cleaned the bettery terminals and cables and said it fired right up.

 

[stockk5]

ok... so
1. Fuel pump works, pumps plenty of fuel up
2. Power to the injector wires.. just no pulse
3. New ignition module/coil and tried a new computer/tbi carb
4. Computer has power, everything else has power just still no pulse..
5. Cut into the injector wires right near the carb and grounded them off of that.. still doesnt send a pulse..

My dad and i are stuck a wall... still no clue on what to do.. still starts up when gas goes into carb, runs fine then for a few secs. Atleast 5 mech's have looked at it.. called a few other friends.. no one has a clue at this point.

If i was to go w/ a carb... what are the exact parts i need? New intake/carb... and fuel pressure regulator? I can leave the computer and stuff in to run the tranny right? thanks for all ur time guys trying to help me w/ this.

 

[sandawgk5]

ok... so
1. Fuel pump works, pumps plenty of fuel up
2. Power to the injector wires.. just no pulse
3. New ignition module/coil and tried a new computer/tbi carb
4. Computer has power, everything else has power just still no pulse..
5. Cut into the injector wires right near the carb and grounded them off of that.. still doesnt send a pulse..

My dad and i are stuck a wall... still no clue on what to do.. still starts up when gas goes into carb, runs fine then for a few secs. Atleast 5 mech's have looked at it.. called a few other friends.. no one has a clue at this point.

If i was to go w/ a carb... what are the exact parts i need? New intake/carb... and fuel pressure regulator? I can leave the computer and stuff in to run the tranny right? thanks for all ur time guys trying to help me w/ this.

How are you checking the injectors? Do you just see if there is fuel spraying out of them or do you have the noid to plug in to see if a firing signal is being sent.

If I missed this in a previous post I appologize.

Ira

 

[Thunder]

So did you ever check the pick up coil.??????
Not the ignition coil. It has nothing to do with your problem. The magenetic pick up coil is the round thingy in the center of your distributor with 2 wires coming off it. Your injrectors will not fire if you have a bad pick up coil.

 

[5kerblaz]

I've had two pick-up coils go bad - one in an '82 K10 with carb and one in current '87 K5 w/TBI. In both cases the engine would crank intermittently. If it cranked, it would start and run. No codes. Replaced with reman. distributors and both worked perfectly (K5 still does).

I'm not trying to poo poo Thunder's suggestion; just my experience. Maybe you can swap your friend's distributor (the friend with the computer) and eliminate that piece of the puzzle.

Hang in there.