No idea what the heck is going on. Im having some very audible knocking under medium load/boost. Also having some spark blowout (try to gas it, it enters boost and falls on its face). My wideband reads 10.5-11 AFR when the pinging occurs.

I switched to COPS after my stock coils failed me. When diagnosing the failed coils, I made many attempts to crank the car. Consequently, I believe I have quite a bit of carbon buildup, as the tailpipe coughed out a sooty carbon slurry when I was finally able to crank it up. I believe this is also what necessitated a spark plug swap, since one plug was caked in carbon.

Here are the things that have changed:

• Toyota COPS
• 10kuF capacitor
• changed trigger angle to 89 (seems outrageous, its the closest I could use to get to 10 degrees BTDC when setting timing, could honestly use some more, 91-93)
• changed spark plugs
• car sat for about a week with a half tank, filled the rest of the way with 93.

The tune remains the same. I am using a MS1 3.0 board with the mkPullup mod. I ran about two bottles of water through the intake via a vacuum hose to try to clean some carbon (too cheap for seafoam). And currently have a whole bottle of some lucas octane booster/carbon cleaner solution in my gas tank. Yet the pinging still occurs.

Could this pinging be related to carbon buildup? or some fault with the coils? Maybe bad gas? Something else?

 

Bump! Still giving me problems

 

maybe you need to find out why your trigger angle has to be set so high to get to 10 btdc first. fix that first?

 

I actually replaced my 10kuF capacitor rated at 10v today with two 4700uF capacitors rated at 35v. Timing changed from needing 90+ to only needing ~87 to be at 10 degrees BTDC. Even 87 seems ridiculous, though. What could cause a high needed trigger angle?

 

1. Having too high of a trigger angle limits the amount of advance that can actually be generated. In other words, the MS may not be able to comply with your spark map in reality because it is "pegged." To change, you'll need to reposition your CAS or whatever the ignition system is using to detect crank angle.

2. You mentioned changing spark plugs. Same heat range? You might be encountering pre-ignition rather than detonation.

Having enough carbon build-up to materially change the compression ratio is unlikely.

 

Retarded my timing tonight, and was able to run 79 trigger angle. Still having what feels like spark blowout, though. Took the car for a short drive, not sure if I had any det or not. will report back tomorrow

Thinking spark plugs may be my next step. I think I replaced my NGK BRK7E's with NGK platinums. The electrode on the platinums is miniscule.

 

I reviewed my MSPNP documentation. I think I had it backwards. It says that too low of a trigger angle (i.e., < 40) limits advance. The MS1 recommendation is a trigger angle around 55-60 degrees. I'm guessing MS3 would be similar? I wonder if this affects the MS's ability to create proper dwell?

Are new plugs NGK heat range 7 like the old ones?

Is the "blowout/det/whatever?" related only to boost or RPM? Or both? If both, you may still need to gap down a bit on the plugs. Regapping platinums is tricky because the tips are so hard.

A sig with details would help. For example, I'm wondering how much boost you're running.

 

ms3 trigger angle it'sdifferent. mines -6.

 

The plugs were heat range 5, went out today and replaced them with some BRK7E's (what I had used before I replaced them) Took it out for a run, and still had the same problem. Ran a little better, I suppose, but still had det/blowout.

blowout and det seems to only be related to boost. I can rev or give light throttle and reach higher RPMs just fine, but boost seems to bring on the det and blowout.

Ill update my sig momentarily

 

Have you verified that your actual spark advance matches your table with a timing light? If you're really getting det (and it sounds like you're pretty sure you are), you need to be pulling back your timing.

 

Hmm... Updated my sig, but it doesnt appear to have updated.

Anywho. Any time I've made a change to the car, I've went back and checked my timing (set fixed angle to 10, adjusted accordingly, etc) its currently set correctly, with trigger angle set at 79. Ill try to retard using the CAS here in a few to try to lower my trigger angle again to see if this helps. Ill report back when I do.

JIC my sig doesnt update:

96 1.8. MS1 v3.0. T25 13 PSI (using the MSPNP base spark map for a 1.8, 94 I believe)

 

I was able to squeeze 68 trigger angle out of it by fully retarding using my CAS. (Ive gone full retard. heh)

Didnt get blowout unless I went WOT, but still have pinging at ~10 PSI at ~11.5 AFR.

Attached is a log of my run.

edit: also, I verified that my timing advances when I rev at idle (timing mark moved when I revved). So its not stuck at a fixed 10 degrees

 

is your timing (belt wise) set correctly?

 

Brain has his trigger angle set to -6. The huge mismatch between his angle and yours makes me nervous. Do you have a reference that describes how this should be setup with MS3? It seems like there is something basic missing.

Also, by verify timing, I meant go to a target MAP and RPM where there is a fair amount of advance and make sure you've got a match. Would require a dial indicator type timing light.

That's an excellent question about the timing belt. If the cam is off, it would affect the CAS. Also, verify that 0° at the timing mark corresponds to TDC on cylinder #1. I usually do that by pulling the spark plug and inserting the oil dipstick into the spark plug hole so I can see when TDC is reached.

Did you post your timing map? Anything unusual about it?

 

i've dealt with 3 ms3's and a diypnp and i've never had an offset of more than +/-8 on all of them. that huge offset you have is not normal. I would pull off the valve cover and timing belt cover and get your crank to 0 btdc (check your #1 cylinder to see if it's at the top) and check the markings on the CAM gears. Personally I'd spend the time to do it just in case to eliminate it as a possibility

 

Im using MS1, with a 3.0 board, not MS3. Should I be able to find TDC on cylinder 1 by just viewing my timing mark? Then take the valvecover off and check my cam alignment via tick marks, correct?

Ill give this a check in the morning (it technically is morning now I guess) and report back.

edit: basemap contained in this tune file: http://www.megasquirtpnp.com/downloa....8%20Turbo.msq

 

just trying to say that the ms3, which is based on the same pcb as your ms1, and even a diypnp, which is a microsquirt using ms2/extra firmware, doesn't sync with the CAS using a crazy offset as you've encountered

 

I would definitely detect TDC either from piston position or from the notch in the crank gear. The timing mark depends upon the condition of the rubber in your harmonic balancer, and they've known to be off, especially with age. If it's off, it could explain a lot of your issues.

You're getting det. I'd leave nothing to chance at this point.

 

ms3 firmware ms1 firmware

 

Just checked my marks... Here are the results

TDC Piston:



TDC Crank mark (looks a bit off in the picture, but I think its because of the angle, looked correct in person.





cam marks:



Looks like the right side is a little lower, but again, it may just be the angle. it looked about 1/2 tooth off in person