Misfire, or terrible tune? MS2E (Logs+Tunes included)
My car idles rough; it's been doing it for a while now, through different motors, two separate rebuilds, two throttle bodies, and a complete ignition+ECU swap.
I've checked my vacuum on the car, and while it's low, carb cleaner on all the intake areas are not yielding any clues to the problem.
99 Block+BP4W Head, 265cc injectors (skinny red/maroon tops)
Exhintake cam mod done
Toyota COPS put in last weekend (was running OEM coil packs before, did the same thing)
Reverant built MS2 Enhanced
ok, ran a simple cop disconnect check on the car this afternoon: Please bear in mind that this is at idle; car revs normally, seems to drive normally, etc... Engine smooths out above 1300 RPM's...
Pulling Cylinder 1 causes the engine to die.
Pulling Cylinder 2 doesn't change anything.
Pulling Cylinder 3 doesn't change anything.
Pulling Cylinder 4 causes the engine to die.
Swapped COPS from Cyl 1 to Cyl 2 and 3. Problem followed the Cylinders, not the coilpacks.
Pulled the plugs; Cyl 1 is fine, 2&3 are sooty. Didn't bother with 4, since we know it's firing.
Took plug 1 out of Cyl 1, and pulled the whole COP harness; resting plug+COP against the chassis, we checked for spark while turning the engine over:
All Coilpacks produced spark, so it isn't the signal wire from the loom for 2&3.
Will be doing a compression check on Cyl 2&3 tomorrow, but this is a fresh build, and I had similar problems with the old build (and a head gasket wasn't the issue then) so I am not really considering that it's a problem; just ticking a box.
Next up is fueling, and more importantly, the injector harness/loom.
Is there a way, with the MS2E (and a bunch of small cups, and some wire to hold the injectors in place, of course) to test fire the injectors for a period of time to verify fueling?
Furthermore, since I'm set on batch-fire, and wasted spark currently; does anyone know what wires run the injectors from the ECU all the way to the injectors? (It's not the ECU, car was running like **** before this.) Since this idle problem has existed before, I'd like to check the signaling wires from the ECU to the injectors to see if there's a fault.
MS output test function is awesome. Tested my fuel pump and injectors today: Pump pushed around 60 psi out, injectors all fired evenly, and dropped the same amount of fuel.
This problem isn't computer related (yet?), nor cop related, nor vacuum leak related.
The valve seats have undone themselves. Not the valves, or the valve train, but the seats, that you lap with the valve... are apparently shot? Engine was rebuilt in toto, apparently the head passed a leakdown test when they set it up before.
Leakdown test with the cams on (each cyl at TDC) and with the cams off yielded the same result of a massive leak through the intake. Looks like the seats have separated themselves from the head? (I'll grab a picture tomorrow when I go back and button up my head-less engine.)
I'm not sure if that's a point and laugh, an expression over the likelihood of the events, or an exclamation over me making a breathtakingly retarded comment...
The first one is deserved, the second one is about how I feel on the matter, and the third one... well, I have no experience machining a head, so if an education is in order, I suppose that's a class I should probably be in...
Don't the seats have to be put in with an oven and liquid nitrogen?
Site Quote: Turbo Kitten is watching you test Compression:
Pictures were terrible in both results, and quality: Leak test into each port yielded consistent leaks across all the chambers. Shipping head off to the machinist; he said it passed a leak-test in the shop, other than needing to grind the valves, the head I provided looked like it had been recently done.
I bought the head as a recent reman two years ago, (Seriously, head was cleaning tank fresh when I got it.)and had similar compression problems down the line (thought it was bad valve seating; not a bad valve seat).
Doesn't feel like the cyl walls are glazed; there's a noticeable difference between the hone grab of #1,4 and 2,3 (2,3 had the lower compression). Probably going to have to drive it like I stole it when I get it back together to seat everything proper.