My Camaro is a 1989 RS in which I recently had a 5.7 block installed. It's an automatic (regrettably, but I get by) and it stalls at a stop when in drive. Putting it in neutral or park usually avoids stalling even though the idle is still rough.

It had been accelerating in a choppy way, but I learned this week that using higher octane gas fixes that because the engine can time itself better, and it did. Driving up or down hills has no effect on engine performance; I want to say that being stopped while facing uphill makes stalling more likely (or happen more quickly) but I may be imagining that.

Recent repairs made:
New 5.7 block
New radiator
New water pump
Throttle body cleaned (or replaced, I will clarify when I contact the mechanic that did the work)

I'm unsure as to whether the distributor had any part of it replaced while they were rebuilding my engine. Again, I'll clarify when I can contact the mechanic.

I have adjusted the idle up and down; it only slightly affects the problem. A very low idle causes it to stall much more quickly if not in neutral or park, and an unreasonably high idle prevents it from stalling at all.

So if anyone could advise at all on this, I'd appreciate it.

 

Welcome to the Club, enjoy the cruise.
First thing the mechanic needs to do is set basic timing and idle, then you should drive the Camaro rather hard, for the OBD I ECM to learn how to 'tune' its engine.

There is a procedure and its pretty simple, but you have to start with basics first.

 

Well the idle is set to a normal idle, and I know for a fact that he did the timing. So what you're suggesting is just keep driving it with the high grade gas in it, and it should learn how to sort itself out in time?

If it doesn't improve, from what I'd read before it could be the fuel pump or IAC; though the engine does increase RPM automatically before it stalls which prevents it from stalling about half of the time, so I would bet the IAC is doing that and that seems like it would mean it's working, correct?

 

Take the Camaro to Advance Auto and have them read the diagnostic codes, if any.
Doesn't hurt, and probably none as you have not mentioned CEL is not on.
Has the O2 sensor been replaced? Doesn't hurt.
EGR valve closing correctly? Some times some grit gets stuck in the pintle valve and holds open the valve. A quick check is reach underneath the diaphragm and lift up and engine will make a change - if so, EGR good mechanically.

Setting the basic ignition timing and idle RPM means adjusting these without ECM control in the picture.
Basic idle RPM adjust is jumper ALDL connector pins 1 & 2 together, turn on IGN, eng off, unplug IAC, IGN off, remove jumper, start engine and adjust idle for 500 rpm with curb idle screw, Torx #20 driver. Engine off, plug in IAC, disconnect ECM fuse #1 & #2 for clearing diagnostic code for about 15 seconds, then replace fuses, IGN on for 15 seconds as ECM is setting IAC for idle, turn IGN off. Now start engine and let it stabilize.

Passenger kick panel is a single wire connector - engine off, disconnect, start engine, time ignition for 6° BTDC, stop engine, connect connector, erase diagnostic code, drive Camaro. You could do this step with the above step after setting basic idle.

A test of IAC is with any load applied, engine rpm remains the same, auto trans in gear, A/C on, lights on, etc.

Sometimes, a total reset of the ECM is needed - kill power to it and start over.
Ensure all vacuum lines are in good shape, first.

 

I'll try those things then. It's interesting what you say about the IAC because I do notice a drop in RPM when I put it in gear versus neutral. If that's the determinant of IAC being good or bad, then that could be the problem.

I don't have any experience adjusting timing; I'll give it a try.

 

is the new engine new? have the lifters been set with engine running.

 

Follow the book as it would be more correct, I'm going from memory and I'm over 40.

 

Did you install a new Chip in the ECM??? If not , this could be your driveability problem.

 

Well I'll say this much, I believe the idling and stalling problems did exist before the engine was replaced. However, I did not have working AC, and so I didn't notice the stalling very much until after I started using the AC (fixed at the same time as the engine) which of course put more load on the engine.

 

It has been a full week since adding the higher grade fuel, and still no change with the idle.

Also, clicking which syncs with the engine revving is a sign of a healthy fuel injector, correct?