Agh! Please tell me that I'm not the only one that's experiencing the same problems with this motor.. My dad rebuilt a '68 Chevy Short-Step, which can be seen in my avatar, and he put a 4.3 Liter V6 in it, which makes no sense because he's owned a Big Block '55 Chevy, a '59 Apache with a 327-4 speed, and even a '71 Trans Am 455 H.O., plenty of Camaros, Novas, Chevelles, Impalas, and he stuck this excuse for a motor in a '68 Chevy? Well, ever since I got that truck as a Graduation gift 4 years ago, it's been acting up. I've blown enough money on it keeping it running, including new heads, head gaskets, injectors, exhaust manifolds, spark plugs, ignition wires, just about everything, including a brand new radiator last year, and a whole new transmission, so it's definitely not the transmission that's causing something. I'm surprised we haven't taken the dang motor out for a complete overhaul! Well, this morning, driving to school on the I-27 South, it died a couple times, and I pulled into the next parking lot, which was a Hastings, and looked it over.. it didn't make sense, my injectors were delivering, i checked around the heads and I couldn't feel anything that would signify a head-gasket leak. Nothing is leaking out of the bottom, and it isn't even time for a oil change. Is it just me that's cursed, or is this problem associated with other 4.3 Liter V6s? Oh, and anyone with a free V8-stick trans.. I'm all ears.
My first car ever was a s-10 with the 4.3! Great motor and the only problem I ever had with it was the oil sending unit. Its basicly a 350 sbc with 2 less cylinders.
As a dad/grandpa, I'm reading between the lines here. Dad did his part, it's been four years, and it's.......... I know a lot of kids that would give their left nut for a dad that furnished them with a truck. The first paragraph of your "problem" is about what you perceive that your dad did wrong with the choice of the motor. Grow up. It ain't the motor's fault, it's the diagnosis. Figuring out the cause of poor performance is the key. Changing the heads and injectors won't make it run better, if for instance there is a bad connection/cam position sensor/crossed wire/low fuel pressure, or what-not. In most cases it's only one thing that causes irratic performance. My advice would be for you, in the future, when you get a malfunction, is "duplicate the malfunction" and only change the component that is causing the irratic performance. Any good mechanics manual, Haynes, for instance, gives you all the information you need to systematically eliminate components that might be contributing to the problem.
I think I missed something. It quits, so you look for oil and coolant leaks? I'd look for a wiring problem first.
I agree. It runs, and dies sometimes. Very well could be as simple as a poor connection to one of about 20 at sensors etc. I would first do a ohms test on the ignition components(Haynes), and make sure all the vac hoses are intact, , and consider low fuel pressure as a place to start checking.
And grounds. And while we are on the subject, does it sputter and farrtt and choke and then die, or does it JUST SHUT OFF??? inquiring minds and all that.,..
If you dont like the engine pull it out and go with a 350 carburated and old school ignition. All easy to trouble shoot and not ever a parts problem if you need something. Some of your problem is lack of diagnosis experience.
It will not make any difference even if put in a killer big block. If you do not understand how a car works you'll have problems. It's expensive, time consuming and frustrating to throw parts at something you don't understand. Make friends with a professional mechanic or learn how each system of an automobile works. Thank your father for his efforts to give you something special. Good luck. Alden
I'll read between the lines here too and guess that your Dad remembers what he used to do with those kinds of cars when he was your age is just one reason he put that 4.3 in the truck for you. I'll also agree with with others in saying it's probably a sensor or other electrical problem. My Dad has an '89 Chevy truck with TBI and it'll just plain shut off while you're going down the freeway sometimes. Turns out it was a fuse.
Correct. As I said before, it ain't the motor. A different motor would not help you learn to think like a mechanic. It's also hard to find a mechanic that knows anything beyond following the instructions in a troubleshooting chart. Most of those will be put off with the fact is's a motor swap anyhow. So it's time you sat down and put that HS education to work for you and read/study/learn, and then apply that knowledge. Public library has all the books you need for motor troubles. My very first test would be to measure the fuel pressure with a gauge and compare that to what it was supposed to be in the vehicle that motor came out of. Good luck.
Granted, I do need to grow up a bit.. I do seem immature when it comes to hot rodding, but I'm young, and dumb, and eager to learn. I probably seem ungrateful, but I just don't want to muck around with V6's.. I do understand how a car works, I just prefer the faster kind. I've been driving for going on 5 years, I've only gotten one ticket, and that was 3 months after getting my license, so that's a lesson well learned (although my first ticket is framed and hung on my bedroom wall). I've never had a wreck. Never raced on the streets. Never had any trouble with Johnny Law. I think that's significant proof that I'm a very mature driver. If I'm going to get into the hot rod business, I need to start learning more about these kinda cars and stuff. And how can I understand what my customer wants if I have no idea or experience of what they're looking for? Yes, it is a TBI, and it just plain shuts off. Yeah, I'm pretty sure it's a fuse too. I found a similar problem last night, and so I went to replace a couple that were having problems to do with my taillights (neutral and stop lights), blinkers, and dash light. Then after replacing two, my dad and I figured that there was probably a short in the fuse box and decided to do that later today after school. So this morning, I had to use hand signals to get my way to school, then I will again on the way home. So.. probably.
he didn't build this truck for me. he built this in the mid 90's and i got it.. maybe 8 years or 9 years after he finished.
So, you're upset that the truck, a gift to you from your Dad, who built it, used it, and thought enough of you to GIVE it to you, needs periodic maintainece after you've used it daily for 4 years? I'd be upset and badmouth him and the truck too if I were you.
I know, I know, I sound ungrateful and stuff. I'm not badmouthing my dad, all I'm saying is, I'm frustrated with this motor. That's it. Please don't make me out to be something I'm trying not to be. I love that my dad gave me a truck, I LOVE that truck, but it's just in such bad shape that it affects me.
You're in college, so you probably know how to read. Maybe you could read a book about cars? Seriously you might get farther with this question on hotrodders.com or another forum that's more specific to that motor.
being a mature driver doesn't make you a better mechanic. i have an inline six and is good enough for me. 4.3's are one of the best v6's out there. only thing i hate are the computers and useless sensors that keep it from runnin fine. could be, if all the electronics are used in the truck, an oxygen sensor or the god forbid catalytic convertor. they can bog down a motor and kill it while runnin.
The rusted truck my father gave me was so worn out it would bend push rods at 55 mph, and to way many other problems to list. Use your truck to haul parts and build your own. There is no better way to learn.
texasred.. When I come to this web site, I look towards to hearing from the more experienced people, hot rodders, and whatnot. I love seeing the encouragement these people have to offer, and I go through this web site several times a week. I'm frustrated, and that's probably why I sound this way, I'm normally happy when there aren't problems, but I guess I just vented on this message board and didn't realize how bad I sound. But your attitude certainly doesn't help. At all. I'm sorry I sound like some ungrateful jerk for a son, but I'm still growing up, I'm still learning stuff. What all of these people have just said are all very useful advice, and I like that. I like all of their separate opinions, and what they're willing to say. I'm surprised they all took time to leave me a message on my topic, and show me that what I'm saying, and how I'm presenting it is what is making me sound ungrateful and immature. And what I'm taking from this is all valuable knowledge and I'm seeing the choices I could make when I get home in trying to fix my truck. As well as advice I can apply in my life in the future when I'm a father of my own, and I realize how bad I was back then. In life, I've learned that even the 80-year old people never stop learning. And what better source to learn from than a bunch of people that's been doing it all their lives? THAT is why I love this web site, and what YOU are saying is not helping that at all. You've got one shot at life, that's it. Do you really want to die knowing that I don't like you because of your remark? I would understand you saying something like "You sound ungrateful and you should be appreciative of your father for giving you a truck. What I would advise is to blah, blah, blah.." but not that remark. That remark was really unnecessary. Sorry, but that was just not right at all. If you don't have anything nice to say, or any advice to offer, then don't say anything at all.
gotta start with the basics. an engine needs 3 things to run, fuel, spark and air. air is pretty easy. fuel - filter good? in tank pickup clogged, etc, etc. Regarding still using the TBI, was it installed properly in the first place? Do you still have a diagnostic plug to the computer to pull error codes (some parts stores will do for free) Get into the problem solving mode.
CherryBomb - I think your getting some good advise here about chasing down the wiring. I also think your follow up posts have a pretty mature attitude for a young guy. You will come out of this more educated, and probably without spending $$$. Best of luck, and disregard Texas Red's BS.
Mechanic parts aren't a big part of my hobby right now.. I'm more of a body-mod guy, and fabrication. I haven't had much of a chance to learn about the mechanics of a motor or trans except for what I read in Rod and Custom, Hot Rod Magazine, Hot Rod Deluxe, Street Rodder, et cetera, so I'm not implying that I am the mechanic. My dad is. I've only done as much as help my dad rebuild a Ford 351. That's about it. I didn't change all of those parts on a guess. I blew out the first gear in my 700-R4 recently and got the new trans to replace that, then a little over a year ago, a co-worker backed our boss' truck into mine, thus damaging the radiator and caused a leak that we couldn't fix til it blew the head gasket, so we got new heads and gaskets to fix that, plus we replaced the radiator. Then the injectors were acting up back in November, so we had to change those out, and the spark plugs, wires, et cetera, were all just replacing the worn ones out. There's just a lot of work I've done to it to simply keep it running. I'm probably just not impressed with my V6, I'm sure there's tons of them out there that would impress me, it's just I haven't seen one yet. And the V6 I have right now never left that good first impression on me. A scar on my mind, probably. You guys probably would have to show me that there's more to a V6 than what I have right now. I'm just a stubborn old school guy.. I would much rather have a simple carburetor V8 and a 4 speed than have a V6 with wires running around it, being really complicated, and a weird shaped intake manifold. But, this is the HAMB, you never know. Maybe I'll get proven wrong on here. I'd love to see that. One of my art professors said a quote I'll never forget.. I think this quote can relate to the hot rod industry very much.. "Simplification is your Best Friend"
Add a ground to the engine and trans. Change the fuel filter. The trouble in the turn signals and brake lites can be the turn signal switch. $0.02
Texas, The TBI system is really a simple setup. When you are troubleshooting you need to keep your thoughts simple. Always go back to the basics. Like someone else said 1. spark 2. fuel 3. air (in and out) Do not get hung up in the idea of the computer. It is imperative that it receive 14.5 volts and be well grounded. Grounds on engine, dash, computer, body. Fuel filters are the biggest "cause" of problems. They are doing their job but get plugged. Really it shouldn't be more difficult to keep running than if it had a carb. Another thing to check is the magnet on the shaft in the distributor. If you can see cracks radiating out from the rivets the signal will be weak, this affects the injector signal adversely. If you want to do this work you need to learn the basics and that includes electronics. They are here to stay and really are bullet proof. Good luck! Alden
If you sit around and look long enough, you'll notice there are only four kinds of poeple in this world, 1) You know, that you know. 2) You know, that you don't know. 3) You don't know, that you know. (That's you bud.) 4) You don't know, that you don't know. Think before you speak, as everything you say can and will be used against you. Fix your truck and quit boobin'!
ok i might be off base here but seeing as how i work on these things everyday you might want to pull the dist cap and check the wires coming from the pick up coil that go to the module they are know to corrode and cause intermittent connections...r
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