cosmick

So I still have my '86 Camaro that was a 2.8, I'm giving it to my new step-son. I'm still daily driving my '94 Camaro with 3.4L and 4L60E.
The entire 7-ish months I've had it, it has always had a dramatic misfire when warmed up, at lower RPM, at above roughly 1/3 throttle.
I tried the old trick of making it flash the trouble codes by paper-clip jumping the terminals in the ALDL connector, no dice. I tried going to Auto Zone, their code reader won't do this OBD1.5.
So I started throwing new parts at it, as they say.
I replaced both O2 sensors, the inlet air temp sensor, and the throttle position sensor. No great improvement. Because it'll sometimes give me full power when cold, above 3500 through 5300 in second, I've ruled out a lack of fuel or weak spark.
I tried driving with the coolant temp sensor disconnected, no change. I've spend dozens of hours Googling.
So next is going to be the knock sensor. Maybe overly sensitive, maybe in too tight.
Driving it this way has been an ongoing hell, but it hasn't hurt anything but acceleration. On a fast trip from SLC to St.George and back, it averaged 24 MPG.
Oh, and the more I drive it, and check the RPM vs MPH, the more I wonder if the 3.23:1 rear gears got swapped for 3.42:1.
The 3.4 would be adequate 95% of the time IF it ran right. Until then, no point in performance upgrades. Mine came with a 3" Magnaflow muffler intended for a Z28, it sounds mean, drones a little sometimes, but I'm keeping it.

58mark

iTrader: (3)

Why does your car even have a knock sensor? The 2.8 didn't have one at all.

cosmick

I'm posting this for guys considering the 3.4, or having trouble with 3.4 swaps. My 3.4 is still running in my '94, just as GM built it 309,000 miles ago.

58mark

iTrader: (3)

Duh, I read that wrong. I thought you were having problems with a 3.4 after you replaced the 2.8 with it

cosmick

Well, if anyone else does a 3.4 swap then has symptoms like mine, they'll know what doesn't help. I'm not 100% sure there's a knock sensor on mine, but if there is one, and if it is causing the PCM to pull timing, then that might explain it. I'm finding it difficult to care about a 3.4, or invest any money / labor into a 3.4, especially since getting my 4.8L LSx into my '87 S-10 is proving so much more hassle than an LT1 would be, and my '94 Camaro would love my 4.8
3500 heads and a turbo should make a 3.4 adequate, but I haven't had a chance to drive any such thing.

58mark

iTrader: (3)

If it's still in 4rh gen, it could be a number of things wrong with it that wouldn't carry over to a swap into a third gen. Coils, ecm, ect

cosmick

Why would you want to keep a dizzy? Especially since you can't keep it with a 3500 top-end!

58mark

iTrader: (3)

because it's a good reliable system, and keeping everything from the 3rd Gen except for the block means it's a very easy swap.

cosmick

The reason for swapping a 3.4 is power without a V8 or a turbo, and for that it needs better airflow to go along with the bigger bores. The 3500 top-end is reason enough, in theory.
I've driven an '87 2.8, an '86 3.4 swap with ported '95 heads and ported '86 intake, and a '90 3.1, both the '87 and '90 had idle problems, and the '90 had VATS problems. My stock 3.4 has none of those problems.
As soon as I find what's been holding it back, I'll have mine as good as an iron-head 3.4 can be, which it already is on rare occasion anyway, and even at it's best, it still isn't adequate power 100% of the time. Maybe 95% at best, and that's intolerable.

cosmick

Car didn't sell, registration expires April 1, gonna pull the running 3.4 out, anyone want a known-good, stock 3.4 around northern UT? Needs valve seals, the misfire is either the ICM ( DIS ) or a fuel pressure issue. On cold mornings it usually gives me one good WOT pull through 1st and 2nd, so there's nothing wrong inside the 3.4

project89

iTrader: (1)

hit me with a price im about 3 hours south of u.how many miles on the motor
got a trans to go with it ?

cosmick

I'm planning trying to adapt the 4L60E to my 4.8 until I can afford a 4L80E from Pick-N-Pull, but for an extra $120 I'll include that, too. It shifts great, all gears work, no slippage, you can drive it.
Not sure what the 3.4 is worth, you may be planning 3500 heads, so me pulling a complete engine with PCM, harness, manifolds and Y-pipe may be more than is helpful, but I don't really have a set dollar amount in mind. Hoping for at least $150.

project89

iTrader: (1)

yeah not interested in the 4l60 , id be interested in the complete engine though
dont need the pcm , but if u have the harness that would be great

how many miles on it ?

cosmick

The car is about to reach 311,000 miles, but the engine didn't smoke at all when I got it with roughly 304,000 miles last spring, so it may not be original, or may have been freshened. Just a little blue smoke on cold start now, so it needs valve seals.

project89

iTrader: (1)

ill let ya know , part of the problem is i wont be able to pick it up till mid/late april

cosmick

3 weeks until I have to park it, if anyone near northern Utah is serious about buying it next month, please PM me to schedule a test drive in SLC this month. $150 cash, firm, complete with manifolds, accessories, y-pipe, PCM, harness, coils, etc.

project89

iTrader: (1)

ill keep u posted , id come and get it for sure but i gota wait for my friend to be around with his truck and he lives in nevada and comes back on the weekends , except him comming back is on hold cause his wife is about 1-2 weeks away form having there second baby , so not sure how soon hes going to get back to utah on the weekends