which 4.3 to get?

[Trevor]

Trevor,

How do you reprogram the computer to eliminate the post cat o2's and the egr and such.

I don't. If you throw a scanner on it, it thows EGR codes, and tranny codes, but no rear O2 codes. I don't hook up the egr, that way it can't do anything about it. The computer for my motor came from a truck with a manual tranny, so the only code I get is the EGR.

 

[sucmah]

Thanks,
Ok, what is the difference between the 96-97 automatic or manual ecm's. I find this out before i make my purchase. It will cost me an extra $100 to get a manual tranny model through my source.

 

[sucmah]

never mind, answered my own question. The only difference will be that i will get some extra error codes(8 i think) without the tranny hooked up in the auto version.

 

[mike d]

90% of the rigs we build here get the SCPI 4.3 in them. IMHO, one of the best motors ever built to put into an offroad rig. Good power, GREAT reliability, cheap/common parts. With the exception of one motor, we've never had any issues at all with any of them. No problems on the trails or at comps. Never had any sensors go bad, never had computer issues, never had wiring issues. GM started using a VATS module (chipped key) in 98. If you go this route, you need a computer from 96 or 97. You can use a motor from 96-2001 though. In 98 they changed a couple of pin locations in the computer, so if the harness is 98 or newer, you need to move 3 wires for it to work with the 96-97 computer. In 2000, they changed a handful of things on the motor (including the balancing), which makes it more expensive for parts, and the interchangability of a few items goes away. In other words, stick with 96-99 for the motor. 96-97 for the computer, and try to get a harness from 96-97, but you can use a harness from 98-2001 if you move 3 pins at the computer plug.

Just my .02

Im putting in a 98 4.3 vortec in my 95 4runner, ive got the original wiring harness, and computer. Can i get that chipped key thing flashed from my computer or some way of zeroing out that security feature. If so do you know where i can get it done. Also Ive got a suit case full of the wires from the chev, what do i really want to keep. and also what do i want to keep on the toyota. Im using the tranny from the chevy so that should just plug right in. But as far as the million others wire coming out of that harness I really dont need all of them do I? I guess I need to turn to both chev and toyota wire diagram and just start to intergrate them some how.?

 

[sucmah]

The most affordable place i have found to work on the 96 and later motors is Jims Performance. www.jimsperformance.com. I had him do a 5.7 vortec harness and ecm cleanup about a year ago for me and he was about 1/2 the price of anyone else for harness and reflash work, and my harness looked better than any "painless" harness ive seen when i got it back. And he will talk to you and answer all your questions. Probably one of the best vendors ive ever dealt with. I am not sure if i am sending him my 4.3 harness though. I might take this one on so i am more familiar with my motor. Well see. You have to atleast do something with the ecm though. It might be worth your trouble to see if a junk yard will let you trade your 98 for an earlier(96-97) ecm that was used with the same tranny as yours. I dont think you can find someone to delete VATS for less than $150. And i know you can buy a ecm for $75.

 

[highood]

i have 4.3 in my 52 and the thing is driving me nuts runs great until about 2 miles down the road and then just falls on its face runs crappy no power stumbles and so on i have put just about all sensors on it new computer fuel pump any thoughts would be nice i am at the point now were i want to unleash my arsenal on it and blow the fawker sky hi sorry for thread robbery

 

[sucmah]

Have you monitered your fuel pressure while driving? I know both my vortec motors(97 and 99) have a guage port on the fuel line on top of the motor. It has a black rubber tire valve cap. Just an uneducated guess.