LosDoritos
Newbie
We’ve been at this since October so I’ll try my best to put every part number here
So I have a 1990 Chevy k1500 with the tbi setup stock.
Then added these
Chevrolet Performance 350 Vortec C.I.D. 330 HP Crate Engines 19433030 Summit PN NAL-19433030
Long tube headers SPN HED-69440
Spark plugs SPN ADO-1 (wires are just part store wires)
Jegs intake manifold 555-513036 (with this we also did an EGR delete)
Trans dapt tbi adapter plate SPN TRD-2202 (we were in a hurry to get done before winter that’s why we didn’t just make one)
Holley 670cfm TBI SPN HLY-502-6
Jet Stage 2 prom chip SPN JET-29005S
Duralast Distributor AutoZonePN BDLG-GM04
Everything else is either stock or stock replacement.
Now with all that being said we’ve set the timing to a lot of things with ecm disconnected properly between 0degrees and as far up to 12 degrees (it seems to like 10 the best which is what the motor booklet says for a vacuum distributor) but no matter what it’ll hesitate, backfire out the throttle body and either stall or feel like it’s missing a good 100+ HP when it finally picks up we’ve tried different electronic distributors, even different gm ignition modules with different timing curves, and to make sure my esc module was good we took the one out of my dads truck, all of which we had laying around (money is an issue with this now so we’re trying to do everything as cheaply as possible)
Basically I’m asking if anyone else has ran into this issue with this motor/tbi combo or even may know tbi well enough to have some resolutions I also don’t really wanna do carburetor bc I live in Ohio and it’s my winter vehicle but winters can be pretty rough (plus I’m already invested deep in the tbi). we have came across a few potential solutions but it’d pretty much be me throwing $100+ at it every time I get paid, so here they are:
1. Ignition coil (I have a spare I just haven’t been able to get up to the shop to swap out)
2. Vacuum advance distributor (bear with me here) we did some research and found out you can wire up the vacuum distributor to the ignition module so the computer doesn’t throw any codes from not having the ignition module. (We don’t have an extra laying around or we’d just try it)
3. The computer is bad. (We highly doubt it’s this bc we had it on a scan tool and everything was reading great but it was something we kept seeing a lot of while researching)
We also VERY HIGHLY do not believe it is faulty wires bc when we have it at 10 degrees it WILL NOT backfire, hesitate, or act any sorts of funny IN PARK, as soon as it’s in gear it’ll hesitate and backfire, it also doesn’t want or even attempt to spin the tires. It also normally acts up more in park when it’s up to temp. I have not tried driving it cold to see if it is fine before it reaches operating temp. It’s very inconsistent
Between me (21) my grandpa who owns a shop and dad who works at said shop, we are all stumped.
If I forgot anything I’m sorry I’ll try to be keeping an eye on this and keep it updated to things I do.
So I have a 1990 Chevy k1500 with the tbi setup stock.
Then added these
Chevrolet Performance 350 Vortec C.I.D. 330 HP Crate Engines 19433030 Summit PN NAL-19433030
Long tube headers SPN HED-69440
Spark plugs SPN ADO-1 (wires are just part store wires)
Jegs intake manifold 555-513036 (with this we also did an EGR delete)
Trans dapt tbi adapter plate SPN TRD-2202 (we were in a hurry to get done before winter that’s why we didn’t just make one)
Holley 670cfm TBI SPN HLY-502-6
Jet Stage 2 prom chip SPN JET-29005S
Duralast Distributor AutoZonePN BDLG-GM04
Everything else is either stock or stock replacement.
Now with all that being said we’ve set the timing to a lot of things with ecm disconnected properly between 0degrees and as far up to 12 degrees (it seems to like 10 the best which is what the motor booklet says for a vacuum distributor) but no matter what it’ll hesitate, backfire out the throttle body and either stall or feel like it’s missing a good 100+ HP when it finally picks up we’ve tried different electronic distributors, even different gm ignition modules with different timing curves, and to make sure my esc module was good we took the one out of my dads truck, all of which we had laying around (money is an issue with this now so we’re trying to do everything as cheaply as possible)
Basically I’m asking if anyone else has ran into this issue with this motor/tbi combo or even may know tbi well enough to have some resolutions I also don’t really wanna do carburetor bc I live in Ohio and it’s my winter vehicle but winters can be pretty rough (plus I’m already invested deep in the tbi). we have came across a few potential solutions but it’d pretty much be me throwing $100+ at it every time I get paid, so here they are:
1. Ignition coil (I have a spare I just haven’t been able to get up to the shop to swap out)
2. Vacuum advance distributor (bear with me here) we did some research and found out you can wire up the vacuum distributor to the ignition module so the computer doesn’t throw any codes from not having the ignition module. (We don’t have an extra laying around or we’d just try it)
3. The computer is bad. (We highly doubt it’s this bc we had it on a scan tool and everything was reading great but it was something we kept seeing a lot of while researching)
We also VERY HIGHLY do not believe it is faulty wires bc when we have it at 10 degrees it WILL NOT backfire, hesitate, or act any sorts of funny IN PARK, as soon as it’s in gear it’ll hesitate and backfire, it also doesn’t want or even attempt to spin the tires. It also normally acts up more in park when it’s up to temp. I have not tried driving it cold to see if it is fine before it reaches operating temp. It’s very inconsistent
Between me (21) my grandpa who owns a shop and dad who works at said shop, we are all stumped.
If I forgot anything I’m sorry I’ll try to be keeping an eye on this and keep it updated to things I do.