Thought i'd give TBI a try on the ole 2f
- Thread starter badass
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This should be the same only it's from a 4.3 conversion ......https://forum.ih8mud.com/40-55-series-tech/43710-4-3-tbi-40-a.html
start at post #24
Throttle cable
Here are the components you will need, throttle cable 88 C1500 350 PU, LC pedal and an old GM pedal.....I used an older cable type LC pedal, but you can use the type that goes thru the firewall, just cut it and weld the GM end on......the GM has a plastic grommet that snaps into the hole, you could fabricate the hole and slot but this is easy
Next position the pedal and mark where you need the hole for the cable, it is a rectangular hole, I drill 4 1/8" holes at the corners then a 1/2" in the center, using a die grinder I connect the dots........first pic is the engine side, other 2 are under the dash
First pic shows the cable snapped into the firewall....then the engine connection, don't get smart and try and find one without the loop, it don't work well......don't ask how I know.......last one is all hooked up under the dash.....
start at post #24
Throttle cable
Here are the components you will need, throttle cable 88 C1500 350 PU, LC pedal and an old GM pedal.....I used an older cable type LC pedal, but you can use the type that goes thru the firewall, just cut it and weld the GM end on......the GM has a plastic grommet that snaps into the hole, you could fabricate the hole and slot but this is easy
Next position the pedal and mark where you need the hole for the cable, it is a rectangular hole, I drill 4 1/8" holes at the corners then a 1/2" in the center, using a die grinder I connect the dots........first pic is the engine side, other 2 are under the dash
First pic shows the cable snapped into the firewall....then the engine connection, don't get smart and try and find one without the loop, it don't work well......don't ask how I know.......last one is all hooked up under the dash.....
- Thread starter
- #143
Alright guys, here's an update, made my stock pedal work with the tbi, converted it from mechanical to cable. will post pics later.
MPG RESULTS, not anywhere near what i thought i was going to get. I though i should get much more.
Truck: Stock 2f everything, 4:88 gears, 35 inch mtrs, soa rear with 4 inch sr front, VERY tall truck. Too tall for my liking.
Before: averaged about 6-8 mpgs
After tbi: I'm getting 11.5 which is half city and half highway. On highway i'm running at 65 turning 3000 rpms.
Not the happiest but, i wasn't expecting 22 mpgs, in my opinion that is impossibe with the 2f. BUT, i was expecting around 15 mpgs to be honest. Throttle response is great though.
Now few things to consider, still not timed properly, i believe timing could be much more advanced than it is currently. Also plug wires are more than 5 years old. Plugs are ngk, but are s***ty cause they have been abused. Rotor is old. Front two tires are both extremely aired down to cover up a horrible death wobble. Rear tires also are not fully aired. These are most likely contributing to the bad mpg. But don't think it would make much of a difference.
2 Problems i have. Alternator is dead and has been dieing for some time now, but tbi killed it, truck doesnt idle with lights and other accessories on. haha So i'm planning on a new alternator within the next week. Also after shutting truck off, then recranking it, exhaust smoke shows that engine has been flooded. So my injectors leak after shut down. Also i have been suspecting that she is still running a bit rich based off of the smell of exhast.. Could this be caused by the bad injectors?
Thanks for everyones help, so far have been sucessful, i've put almost 1000 miles on her since completion and she has done great.
MPG RESULTS, not anywhere near what i thought i was going to get. I though i should get much more.
Truck: Stock 2f everything, 4:88 gears, 35 inch mtrs, soa rear with 4 inch sr front, VERY tall truck. Too tall for my liking.
Before: averaged about 6-8 mpgs
After tbi: I'm getting 11.5 which is half city and half highway. On highway i'm running at 65 turning 3000 rpms.
Not the happiest but, i wasn't expecting 22 mpgs, in my opinion that is impossibe with the 2f. BUT, i was expecting around 15 mpgs to be honest. Throttle response is great though.
Now few things to consider, still not timed properly, i believe timing could be much more advanced than it is currently. Also plug wires are more than 5 years old. Plugs are ngk, but are s***ty cause they have been abused. Rotor is old. Front two tires are both extremely aired down to cover up a horrible death wobble. Rear tires also are not fully aired. These are most likely contributing to the bad mpg. But don't think it would make much of a difference.
2 Problems i have. Alternator is dead and has been dieing for some time now, but tbi killed it, truck doesnt idle with lights and other accessories on. haha So i'm planning on a new alternator within the next week. Also after shutting truck off, then recranking it, exhaust smoke shows that engine has been flooded. So my injectors leak after shut down. Also i have been suspecting that she is still running a bit rich based off of the smell of exhast.. Could this be caused by the bad injectors?
Thanks for everyones help, so far have been sucessful, i've put almost 1000 miles on her since completion and she has done great.
- Thread starter
- #144
I installed a new alternator last week. I put a reman cs-130 in there so i got 105 amps now.
BUT, it still idles funny. Always misfiring. when you turn on any accessory it still stumbles and eventually will stall sometimes. When i'm driving on highway for example, i am turning 3000 rpms, lights are on, and when i turn heater on or wipers, the lights dim. If my charging system is working properly, then why would lights dim??? hmm...
These are minor problems, i've probably put about 1500 miles on her so far and i'm just pointing out some problems. Advice is appreciated.
BUT, it still idles funny. Always misfiring. when you turn on any accessory it still stumbles and eventually will stall sometimes. When i'm driving on highway for example, i am turning 3000 rpms, lights are on, and when i turn heater on or wipers, the lights dim. If my charging system is working properly, then why would lights dim??? hmm...
These are minor problems, i've probably put about 1500 miles on her so far and i'm just pointing out some problems. Advice is appreciated.
From what ive read about the whole tbi thing, everytime you add something different to your engine setup, the ecu will have to relearn itself and it will stumble for a while until it is solid. Im thinking could be what is happening since you added that alt. that is my best guess.
glad to hear you got like an almost full 5mpg better, thats a big deal!
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Yes all that can make horrible fuel mileage. Why not just fix your death wobble? What are the condition of the spark plugs? What is the gap?
Have you checked the pattern on the injectors with a timing light? Have you done any data logging?
Have you rebuilt your injectors?
How did you wire the alt up? How is the power run to the ECU?
Your using your stock distributor? Have you adjusted the pickup to be as close as it can to the trigger? It needs to be as close as it can without touching.
Get your battery and alt checked. ECU has to see 12v when it starts seeing volts lower than 10 it will go into limp mode. At this point it thinks your battery is dead and just wants you to get to safety.
Also check all grounds. There is a ground from the ECU that needs to be attached to the engine in a very well gounded spot. The engine als need to be grounded as well as the body. DO not run your main power to the ECU through the OE fuse block. It also needs a good connection and the proper size wire.
Have you gone through the procedures for resetting the IAC?. You sure you don't have any vacuum leaks?
- Thread starter
- #151
I finally replaced all bushings tonight and tightened all nuts and bolts, so no more death wobble. tires are aired up
what should gap be on ngk plugs?
haven't checked pattern of injectors, but i took the advice of someone here and basically advanced the timing until the starter "jumped" and then backed off a bit. no data logging,
havent rebuilt injectors, the truck i got the tbi off of was really clean but had well over 200k on the clock. I just ordered this from ebay. eBay Motors: 86-95 CHEVY S10 ASTRO 4.3 V6 TBI FUEL INJECTORS (item 350140117668 end time Dec-14-08 15:46:08 PST)
- Thread starter
- #152
How did you wire the alt up? How is the power run to the ECU?
i don't think it wired correctly, all i did is ran a wire straight to battery, thats it.
Your using your stock distributor? Have you adjusted the pickup to be as close as it can to the trigger? It needs to be as close as it can without touching.
Its pretty close but i'll see if i can get it closer.
Get your battery and alt checked. ECU has to see 12v when it starts seeing volts lower than 10 it will go into limp mode. At this point it thinks your battery is dead and just wants you to get to safety.
i checked it with a volt meter and at idle (500rpms and rough) she barley has above 12v, rev up a bit and easily hits over 14v.
Also check all grounds. There is a ground from the ECU that needs to be attached to the engine in a very well gounded spot. The engine als need to be grounded as well as the body. DO not run your main power to the ECU through the OE fuse block. It also needs a good connection and the proper size wire.
power for ecu run directly to battery, i have a few wires grounded, is there one in particular that is very important, if so which?
i don't think it wired correctly, all i did is ran a wire straight to battery, thats it.
Your using your stock distributor? Have you adjusted the pickup to be as close as it can to the trigger? It needs to be as close as it can without touching.
Its pretty close but i'll see if i can get it closer.
Get your battery and alt checked. ECU has to see 12v when it starts seeing volts lower than 10 it will go into limp mode. At this point it thinks your battery is dead and just wants you to get to safety.
i checked it with a volt meter and at idle (500rpms and rough) she barley has above 12v, rev up a bit and easily hits over 14v.
Also check all grounds. There is a ground from the ECU that needs to be attached to the engine in a very well gounded spot. The engine als need to be grounded as well as the body. DO not run your main power to the ECU through the OE fuse block. It also needs a good connection and the proper size wire.
power for ecu run directly to battery, i have a few wires grounded, is there one in particular that is very important, if so which?
- Thread starter
- #153
new day new problem.
replaced the dizzy cause the other one went bad. Started up fine the first time. Now for the 3rd time, after sitting overnight outside, it won't crank, the first two times it did this i fiddled with it for a few minutes and managed to get it started but this morning it won't fire. It is pretty humid outside if that makes a difference.
No spark at all. Pickup in dizzy looks pretty new and is set in the right spot, but i'm suspecting bad coil or ignitor. wtf. any ideas??
replaced the dizzy cause the other one went bad. Started up fine the first time. Now for the 3rd time, after sitting overnight outside, it won't crank, the first two times it did this i fiddled with it for a few minutes and managed to get it started but this morning it won't fire. It is pretty humid outside if that makes a difference.
No spark at all. Pickup in dizzy looks pretty new and is set in the right spot, but i'm suspecting bad coil or ignitor. wtf. any ideas??
Do you have water tight connections to the ignition module? I use to have problems when it would rain (more than once here in Western Washington) or splash through a puddle. Siliconed up the non weatherpac connectors AND the seams of the ignitor. Remember, it was designed to sit under the distributor cap.
- Thread starter
- #155
there are three plugs on ignition module, 2 of them are from the harness and have the squishy rubber grommet type stuff in them. the other one that runs to the dizzy is not part of the harness and is not weather sealed. Is there a way of telling if it is the coil vs the ignition module?
When i leave the ignition on for about 20 min, the module gets "farily" warm. Don't know if that means its working or not. Coil from store is 20 bux vs module at 40 and are non refundable, so i'd like to buy the right thing the first time.
Another thing to consider, for the last few starts it has turned over many more times than it used to before it fired... Don't know if that means anything, plugs and wires are old, but were working fine. Thanks.
When i leave the ignition on for about 20 min, the module gets "farily" warm. Don't know if that means its working or not. Coil from store is 20 bux vs module at 40 and are non refundable, so i'd like to buy the right thing the first time.
Another thing to consider, for the last few starts it has turned over many more times than it used to before it fired... Don't know if that means anything, plugs and wires are old, but were working fine. Thanks.
- Thread starter
- #156
ok, so i just tried somethin, turned the dizzy fully advanced and hit the starter jerked, so i have spark,
i kept retarding dizzy until no jerk, but still won't fire... why is it at full advance engine shows signs of having spark?? but when retarded spark dissappears... hmmm.... maybe not strong enough spark?
i kept retarding dizzy until no jerk, but still won't fire... why is it at full advance engine shows signs of having spark?? but when retarded spark dissappears... hmmm.... maybe not strong enough spark?
get a damn timing light, disconnect the tan wire to set base timing and be done with your "timing" issues. timing is not your primiary problem. Its a problem in the fact you never set it properly, but not the underlying issue.
Get someone(beg, or whatever) to set you up with a correct prom with the right .bin file on it. this will make things alot easier to troubleshoot.
Youre playing darts in the dark.
Get someone(beg, or whatever) to set you up with a correct prom with the right .bin file on it. this will make things alot easier to troubleshoot.
Youre playing darts in the dark.
- Thread starter
- #158
dude are you serious, i this has nothing to do with timing, i've driven almost 3000 miles on this conversion with the timing set the way it was and all of a sudden when it doesn't crank the problems is timing huh?
dude are you serious, i this has nothing to do with timing, i've driven almost 3000 miles on this conversion with the timing set the way it was and all of a sudden when it doesn't crank the problems is timing huh?
?!?!?!
You said that you replaced the distributor. You cannot replace a distributor and expect the engine to run properly without setting the timing.
Do you have any kind of heat sink for the ignitor? The distributor is the heat sink when installed as designed. I used an ingitor heat sink from a VW. Not that this is your current problem, but if the ignitor isn't cooled you will shorten it's life a bit.