How bout everything else on the engines like timing belts, water pumps, headgaskets, etc. How do they compare?
But also the opposite can be done to improve MPG and reduce emissions. Slowing both tip in and throttle response creates a software imposed restriction to limit jack rabbit starts or stomping the throttle to the floor.
Iāve read posts on other boards with people speculating how electronic throttle is causing the delays due to signal lag. Give me a break! A properly design DBW system could actually improve response over a cable based system. A uP can see not only the displacement of the pedal but the RATE at which it is being displaced. It can then predict where it is going to be in the future and start adjusting the throttle position based on that projection. But doing that is not in the interest of the vehicle manufacturer. Reducing emissions, increasing fuel efficiency and limiting mechanical stress are things they value more than providing uber fast throttle responseā¦ Given a choice, Iām on the latter end of that spectrum 
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Not sure where that question comes from . They are made by different suppliers and I seriously doubt if there is any difference at all .
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more modern
more accurate
less moving parts
slightly better fuel economy
I could go on . . .
Not that common
far more common to have to replace the iac and/or throttle cable, if driving an older vehicle . . . at least in my experience
None of those GM engines you mentioned have timing belts
Please go on! I meant chain not belt, sorry
Since you seem to be interested in the older trucks with the 4.3, 5.7 and 7.4 . . .
They definitely had problems with the lower intake gaskets deteriorating
The 4.3 and 5.7 were especially bad
Not many problems with the head gaskets
Most of the time that coolant got into the crankcase, it was the lower intake gaskets crumbling, which sometimes allowed coolant to literally gush into the crankcase
pretty much all of them eventually had leaking engine oil cooler lines or trans cooler lines
water pumps are cast iron, no plastic impeller to worry about, but they only last so many years, then they start leaking. no big deal
every once in awhile, the distributor drive gear would wear out, resulting in no spark and no start. you can replace just the gear if you want to be a real cheapskate
the 4.3 and 5.7 had a few variations of csfi . . . central sequential fuel injection. The early version had a central injector body, nylon lines going to poppets at the end. Sometimes the poppets would get stuck or the lines would break. The newer ones had mini injectors at the end.
The 7.4 had true efi, but you have to remove the plenum to get to it. Slightly more reliable than csfi, in my opinion
On the 7.4 the egr pipe tends to develop a hole, which in turn can damage the engine wiring harness
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Thanks thatās the stuff i want to know. I replaced a few of the oil cooler lines on the 4.3, Real fun. Now how about the vortec problems?
I hope that was meant to be a joke
Itās pretty difficult to replace engine oil cooler lines on a 4x4 Jimmy/Blazer with the 4.3 . . .
Youāre going to have be a LOT more specific
As @FoDaddy mentioned, āVortecā could almost mean anything
How about you tell me exactly what engine, what truck, and what model year youāre talking about . . .
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Yeah it was a joke 91 blazer and 91 jimmy 4wd lol
The 90s 4.3 vortec in the jimmy or blazer and the 99 350 vortec in an escalade
Db, in fairness, the last half ton with a 350 was built 20 years ago. So itās a given youāll get trans cooler and oil cooler line leaks eventually. Heck, my wifeās 2013 Toyota seeps a little oil somewhere at 120k miles. Not enough to be a concern yet though.
I donāt know what people are doing to throttle cables to warrant needing replacement. They generally last longer than I want to keep the vehicle. I replaced one that was binding on a truck I bought with over 200k miles. But it had been used as a mud toy.
I agree that since the vehicle is older more things will need replaced. I took that as a given. Whether itāll need more replaced in as many miles as a drive by wire truck, I donāt know. I figure itāll work out about the same in most cases.
I think what youāre saying is any 1/2 ton truck with a 350 era motor (tbi or vortec) is going to be either worn out, already rebuilt, or so old (even if low miles), everythingās going to be prone to leaks. Which I agree with.
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From the posts we get here electronic multi-port injection seems to be more reliable & easier for diy diagnosis and repair than tbi. Iād prefer a car w/a carburetor to one w/tbi.
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Well, thatās hard core old school thinking. Iāve owned too many TBI systems to recall. Very few ever had any real problems. When they did, it was easy to repair. FAR easier than any carburetor I ever owned. I even tore the carb and ignition system off a Wrangler and installed a Chevy TBI system. That thing ran trouble free for a decade before it was traded in on a new Rubicon. As opposed to the carb which was a frequent source of frustrationā¦
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The TBI on my '95 Suburban gave me no problems for 12 years, up to when we got rid of it. Much better than Iād expect a carb to do.
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FoDaddy has the best comment about TBI engines ever.
āFor the 350 the Vortec engine has about 45 more horsepower and more torque, it also doesnāt fall flat on itās face above 3500 RPM.ā
I currently am running a 130,000 mile 95 Silverado with the 5.0 TBI. Itās super reliable, and does extremely well off the line - has good torque - can pull a fully loaded trailer no problem - but the top end is MISERABLE on the highway. The truck canāt pull itās own weight out of the way to pass on the highway. It has a 4500rpm redline even!!! Its a PIG on the highway turning rpms.
Iāve owned a few TBIās 305&350, a 350 āVortecā, and one older 5.3 cable LS. While I applaud the simplicity and reliability of the TBI setup - and itās a major selling point to me on that alone, I find myself wishing for the more refined and better flowing Vortec or LS engines constantly.
Add to that the miserable old 4l60e that canāt keep a gear on the highway since the engine cant pull the vehicle once up to speed. Constant down up down up shifting if thereās the slightest grade.