Thought i'd give TBI a try on the ole 2f

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Do you have any way of monitoring the ALDL data? If I remember correctly, you should have about 15 steps at warm idle on the IAC. If you can read the data, just turn the screw in or out to achieve 15 steps. I don't remember now what tables I had to change, but I did have to make changes to get a good start in the colder months.
 
When I did the last one I used the stock gm cable bracket and an accelerator cable from a van(longest one avail) then I cut the pedal from the same van for the proper attachment and welded it to the stock cruiser pedal . Then I made an adjuster for the cable which mounted to the lower part of the firewall . If you can't figure out the downey setup I could get you a few pics if you want to go this route. Mines been working good for about 6 years like this . Not sure about the low idle thing though , I've built four FI systems for landcruisers using gm tbi's and have never experienced that issue . I have always used gm distributors though. (don't know how that would have any affect? ) What does downey say about it?
 
OlympiaFJ60 said:
Do you have any way of monitoring the ALDL data? If I remember correctly, you should have about 15 steps at warm idle on the IAC. If you can read the data, just turn the screw in or out to achieve 15 steps. I don't remember now what tables I had to change, but I did have to make changes to get a good start in the colder months.
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Please elaborate, i don't know what 15 steps means. Which screw???

Also, i got the gas pedal working so no more problem there, all i have to do now is route the new return line and take her for a test drive tomorrow. :bounce::bounce:
 
This is how I hooked mine up. I used the stock bracket that was on the TB and flipped it. and drilled two new holes. Works great.

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My EPROM is custom for a 2F. Did you set the timing correctly? Have you reset the IAC? You sure you have the wire for the cold start connected correctly?
 
So i took the truck out for test drive and it was HORRIBLE, backfiring through tbi, NO POWER, driving like s***. No longer running rich though after i drove it so that's a good thing, then......























I got out and advanced the timing a bit and HOLY LANDCRUISER GOD, runs beautiful, no misfiring, REDICULOUS POWER, THROTTLE RESPONSE. So timing was the culprit. However, still need replace IAC VALVE cause i'm pretty sure that is the problem with my no idle and no cold start. Will replace that and let yall know what happens. Regardless she's taking a 120 mile round trip tonight to tuscalooosa. Later.
 
Another update, drove about 20 miles and as i pulled into the driveway, started to run rich again real bad, misfiring, and idle got horrible, even with the idle speed screw turned in. WTF. Codes are map sensor, running rich, and no signal from knock sensor. Tbi is making a whistling sound if i turn the idle speed screw down, almost like it has a vaccum leak.

Right when i thought she was running great this happens.

I still have not set timing correctly.
 
badass said:
Another update, drove about 20 miles and as i pulled into the driveway, started to run rich again real bad, misfiring, and idle got horrible, even with the idle speed screw turned in. WTF. Codes are map sensor, running rich, and no signal from knock sensor. Tbi is making a whistling sound if i turn the idle speed screw down, almost like it has a vaccum leak.

Right when i thought she was running great this happens.

I still have not set timing correctly.
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MAP needs max vacuum, make sure you have it plumbed to the correct port.
Knock Sensor on the 2F if it's working should NOT be mounted into the engine block, as the solid lifters will set it off all the time, I would mount it in a bracket and mount the bracket in rubber.
There is one port on the TBI unit that OEM was the PCV it is a "design" vacuum leak, I plugged it on one of my conversions and almost never traced that down.
Are you going into closed loop?
Do you have a way to monitor live data or just a code reader?
Was the truck running absolutely perfect with the carb?
 
Timing.........advance until it "kicks" against the starter, then back it off a few degrees . you will be within a couple of degrees
 
too tall said:
When I did the last one I used the stock gm cable bracket and an accelerator cable from a van(longest one avail) then I cut the pedal from the same van for the proper attachment and welded it to the stock cruiser pedal . Then I made an adjuster for the cable which mounted to the lower part of the firewall . If you can't figure out the downey setup I could get you a few pics if you want to go this route. Mines been working good for about 6 years like this .
Click to expand...
too tall,
Could you post a couple pictures of your set up, including the distributor?
Thanks
 
Texican said:
MAP needs max vacuum, make sure you have it plumbed to the correct port.
Knock Sensor on the 2F if it's working should NOT be mounted into the engine block, as the solid lifters will set it off all the time, I would mount it in a bracket and mount the bracket in rubber.
There is one port on the TBI unit that OEM was the PCV it is a "design" vacuum leak, I plugged it on one of my conversions and almost never traced that down.
Are you going into closed loop?
Do you have a way to monitor live data or just a code reader?
Was the truck running absolutely perfect with the carb?
Click to expand...

Don't know what closed loop means, don't have a way to monitor live data, was running perfect with carb.

Good idea with the timing. Thanks.

However it is still running rich as s***, when i downshift and floor it, it billows black smoke.:censor:
 
badass said:
Don't know what closed loop means,
Click to expand...


I'm going against my better judgment, getting into this........
seeing that you are friends with Bodean:eek::doh:

A cold engine needs help to run, the ECM does this, when the O2 sensor and the CTS get warm.......to a pre programmed set of parameters, then the system goes into closed loop, this means the various sensors have taken over the running engine and make adjustments based on throttle input etc.

You are flying a plane in a blinding snowstorm with no instruments without a way to see live data.

Fuel pump pressure?
The TBI will not tolerate way too much pressure, the regulator can't compensate if the pressure is way too high, found this out when a customer accidentally installed a Vortec pump in TBI truck.....

Of course if ya don't get it going, you can Bodean the event, he brought pictures of his ride forever, we almost decided he did not own a rig.
Butch
 
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Probably not a help to Badass but I was wondering about the idle screw on the GM TBI. Does it just set the butterfly open a little?

I struggled with the megasquirt system (running ignition only) and a newly fitted Weber DGMS38, ran well but rich at first then ran bad and missed, thought it was the ignition failing but the rich running had fouled the plugs.

Also a thought on fault finding, if you can find who the IAC valve works you could force the inputs and check for correct operation and polarity.
 
badass said:
so clean out plugs or just replace em, cause it is misfiring too.
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I had an good clean old set from another engine, fouled ones were fancy platinum things that a vendor had sent in error.

Haven't done anything with them yet, don't really know what I can do, perhaps I will refit and see if a properly tuned engine can burn the fouling off or put them in the dishwasher while :princess: isn't looking?

Sort of put me off buying fancy plugs if I happened to feel like wasting money.
 
so i went to start her this morning, and nothing, no spark and as a result of that the ecm doesn't allow any fuel to come out of injectors.

It did this twice when i drove it yesterday, after i shut it off, it wouldn't start.

I have power going to my coil, dizzy, and module, wtf. How does it just lose spark overnight??
 
Need to make sure the pickup in the distributor is as close as you can get it to the star wheel.

Think about it. If it doesn't know your cranking it won't send fuel. Check you wires for good connections.
 
Hey, great thread.

I plan on installing a GM TBI this winter so I am following your progress with great interest.
You have received a great deal of input from guys with a lot of first hand experience so I am a little hesitant to butt in.
But for what its worth.
Downey's installation manual and other sources state that the speed sensor must be functioning properly to control idle speed and mixture. The altered speed sensor you are using may not be.

Thanks for the insight Heron Jefferson State Cruisers
 
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