he said it's bad compression on cylinder 3 others are okay
Bad compression or ZERO compress. Big difference.
He was able to start the card by advancing distributor timing and holding accelerator to floor.
...suggesting a flooded out engine for whatever reason.
He suggests to put a new engine.
They all do...
Initially was getting P1505, put a new IAC. Now I am getting P0505. Based on forum search, I put new distributor cap and shaft.
Quite the stretch going from an IAC to a new distributor, when both codes are for the IAC.
Still same issue, car cranks but no start.
Any possible help from you guys? Regards and thanks a lot.[/QUOTE]
If your IAC is bad, it'll be tough to start, much less idle, but it should start and maintain a steady rpm with you holding the throttle open a bit, if the IAC is actually malfunctioning in such a way that the ECM can't control the idle.
I'd put the old distributor back in, put the old IAC back in, make double sure the rotor is screwed down in place and use lock tight on it (common thing for that screw to fall out and the rotor to spin freely on the distributor shaft causing the engine to die).
Put in a set of NEW NGK plugs, reset the base idle, reset the base timing, according to the proper procedure (see the stickies), and see what happens.
But that's only if you've got low compression on cylinder #3. Low compression won't necessarily make an engine NOT run. Might run just fine, maybe burn a bit extra oil or be a bit down on power, maybe have a bit of a stumble at idle, otherwise, probably wouldn't notice it.
If you've actually got ZERO compression on cylinder #3, then you're probably going to have to pull the head and see what's up. If the timing chain jumped more than one tooth, ya, could've smacked #3 valves causing zero compression there. Possible, but not likely on a 123K engine with otherwise good components, unless the upper tensioner has never been changed, which is also likely as the upper tensioner tends to wear out around 100K+ miles causing the engine to sound sorta like a diesel or a loud sewing machine. Next question is what were you doing when it happened? Accelerating? Decelerating? Steady speed? Timing chains tend to jump when rapidly changing RPMs, generally not at a steady RPM. And all three times the rotor hold down screw has fallen out on my GA16DEs has been during steady RPM operation.
What I'm guessing happened is that the rotor hold-down screw fell out, causing the rotor to spin as described above, and the engine died. After awhile of dicking around, trying to get it started, maybe the rotor got 'stuck' in a position where it stayed put. The 'mechanic' turned the distributor cap to reposition it somewhere close to the correct timing setting...which is further more why it'll only start if it's floored.
But I'm just guessing...