jeepguy553

$61 stuff
1.) Fuel pump isn't working worth a crap. I know this isn't PROM related. :rantoff:
2.) HUGE knock counts for some reason or other. The engine has little or no power in certain RPM/MAP cells. Is the only way to tune SA tables trial and error? I got 1299 knock counts in 800rpm x 50MAP within a 10 minute run around the neighborhood. That's only one cell. Should I just zero out the Coolant Comp SA table and go from there? I already have the PE TPS Threshold set at 80%, so it probably isn't going into PE mode.
Grrrr.....

Ronny

iTrader: (1)

hmmmm. possible timing chain noise OR exhaust rattle. as a side note i just listened to a car yesterday that has forged pistions. bad cold rattle startup. sounds like it is pulling out timing. right?

Grumpy

Is it showing any actual knock retard?.
What is the timing actually doing?.

Remember if you 0 out the table, you also have a bias, depends on what editor your using.

dimented24x7

iTrader: (2)

Assuming your not having fueling problems,

1299 knock counts is a good of knock given that thats really actual knock counts/256. Does the ecm set any codes? Might check for an open circuit. If the input for the knock counter is left open the counter will basically jsut go crazy and cause all kinds of knock to be reported. If the ecm is on and the knock counter jsut keeps advancing then suspect a problem.

Zeroing out the coolant SA correction table is a good idea. Itll jsut get in the way. Dont use it untill the timing is set up. Basically its trial and error with some educated guessing and experimentation to see what works. The only way to tune it really is to look at performance while monitoring knock counts and making any necessary adjustments in fueling, although the knock sensor itself is far from fool proof. To see if it really is a timing problem, pull around 3 or 4 degrees out from the areas around where you get knock and see if it helps. Also look at the datalog and see where the knock is occuring. If it happens only on tip in or shortly after then maybe its a problem with not enough AE. I had to add a good deal of MAP AE and an s-load of TPS AE to keep my car from going lean and detonating when I got on it. Too much timing can also cause this as well as power loss. See if pulling some timing out around those areas helps.

jeepguy553

Now I did notice that it went lean when I opened the throttles up a little. I got a BLM of 131 once. I am about to zero out that Coolant SA table right now. Should I zero out the bias too?
I am also about to go outside and blow some compressed air through the fuel lines to see if the pump just can't get to the fuel. I know there's gas in it because I put $10 in it yesterday.

steve8586iroc

I'm just curious as to what type of knock sensor you are using on your AMC360ci engine.

And $10.00 of gas, isn't that about a gallon and a half these days.

Steve

jeepguy553

I am using an OEM knock sensor. It threaded right into the drain hole on the side of the block.

steve8586iroc

OEM as in GM knock sensor? I'm wondering if that might be part of the problem. The harmonics of your engine are defferent than that of any GM engine so it's not going be be as accurate as it would be in the application it was intended for.
Just a thought.

Steve

jeepguy553

Hmmm...I am listening...please go on, Steve.
Yes. OEM as in GM. I have seen them used before on AMC engines and they work fine. I am not using a gear timing set and my coolant system is very well sealed and burped. I'll get a screen shot of the Spark Counts table from WinALDL and post it for you guys to peruse.

jeepguy553

Here it is

Grumpy

Knock detectors are most heavily influenced by bore diameter. Then angle from the cylinder centerline, as evidenced by the mercruiser 45d offset to desensitize the K/S..

A long time ago, I played with optimizing ESC modules and K/S. As I recall there was less then 6 (proably more like 4) degrees difference between them. Wound up with the Buick 231 module and 350 K/S.

steve8586iroc

I was under the impression that each GM engine used a different knock sensor because each one has a different block. Even the 305 and 350 sensors are different because of the differences in there blocks due to bore size. If I understand correctly this causes the knock to have different frequencies so the knock sensor has to be tuned for each application.( ie... each size engine)

If I'm wrong I'm sure someone will set both of us straight.

Steve

jeepguy553

What you both are saying makes sense. Still, though, would the k/s cause me to see 1299 counts in the idle area? What about the knock in the other parts of the table? there are other numbers that are around 300-400 counts.

Low C1500

Is your valve lash set correctly, also an exhaust leak could give counts.

jeepguy553

There may just be a small exhaust leak. I think there is a pinhole leak in one of my pipes before the muffler.

Grumpy

They did.
Bore diameter is just one parameter, and once you change enough other items, they can overwelm that one parameter. Take the guys that just run the injectors static, and run on the K/S. They add so much fuel, that the combustion process is so different that it can mask the acoustic signature so as to not trigger the K/S. So by not triggering the K/S they think they are somehow safe. Until they yank the motor, and see the corners of the pistons are missing, or the rod bearing journals are oblong.

IMO, they should have called it the *Bad Noise Detector*, since it can miss some forms of detonation, pre-ignition, and falsely trigger on lots of mechanical problems.