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I drove 90 miles yesterday and watched some of the numbers in the MXlink over time.
Couple notes first off:
-LT FT on bank #2 went as high as 12% and 7% on B1.
-Idle not returning to +/- 750 and brake booster?
Later I setup the graphing program to watch cyl #1 and #6 with the engine RPM and FT1.
Now that the misfire is visible, it's apparent it's occurring very frequently like every second or two. It seems to have a pattern on steady driving and may be constant on idle.
red line is RPM - ignore green line in this example
In this image I had changed the graphing points so don't compare the colors from the previous image - here you can see cyl #1 is misfiring steadily (I was driving at around 40mph at 2500 RPM I remember)
It seems like when I let off the gas LT FT spikes up
I know some of this is sloppy data reporting but I'm still tinkering with this app trying to figure out what to grab but you can see the misfire now and it's very frequent and sometimes constant.
Now, this brings me to this issue which popped up again. Basically after pressing the clutch in and going to neutral (not that neutral matters) the engine RPM has about a 50/50% chance of actually going back to idle, or it gets stuck at 1200-1300RPM and won't go back down. I had this problem before and thought it was something on the TB but it comes and goes. You can see this ithis picture just being at a stop the idle is at ~1300 and won't go back no matter how long I let it sit. I have to rev it really high and let it 'fall' back down. after accelerating up into 2nd for example and going to neutral and stopping RPM won't return to +/-750
I started making an early hypothesis that it had something to do with having the brake pressed while I pressed the clutch letting the RPM fall, but I couldn't consistently recreate it. It **seemed** like if I had the brake pressed > clutched in > the RPM would not stop at 1200-1300, but if I did not press the brake and cluctched in the idle would go back to 750. However I couldn't really confirm this consistently.
Later I was testing the idle at a stop and pressing the brake pedal and pumping it firmly and I could make the engine RPM rise about 50 over a few seconds.
Here's a graph and I marked where I pumped the pedal a few times and held it very firmly down
.
I don't know if this could be connected to the significant misfires I'm seeing - I think the many helpful people in this thread are probably on to something about a valve or compression. Later today I'm hoping to check the cam teeth.
I turned it around once and I first lined up the teeth to the arrow and the bump on the cover - this is what it looked like - notice the WHITE line on the crank pulley is NOT lined up exactly with 0. I snipped all the images together so it's easier to see instead of separate pictures. - keep reading though -
Then I rotated the engine over again all the way and put the WHITE line on 0 - THEN looked at the teeth-
the exhaust cam is maybe off by a SMALL amount ?
The crank and cam alignment looks fine and pumping the brakes always raises the rpm like that.
The high revving after clutching in intermittently means the tps likely needs to be adjusted to read lower as the idl pin is not always engaging, if it is set too close to the transition point it sometimes falls on the wrong side and blipping the throttle can help re "set" it at times.
It is also possible someone tried to raise the rpm in the past via the throttle stop screw, or the throttle cable is too tight, both of those will cause the throttle to hang which also increases the tps value.
If the tps is out of adjustment range and you can't get it back in, then one of those is the likely culprit.
I have actually seen the tps being in the wrong position alone can cause misfires, so worth taking the time to make sure it is set correctly.
I would at this point double check the timing is set correctly with a timing light, but the tps needs to be in the right position or it wont go into diagnostic mode when you put the jumper in the diagnostic port.
When you put the jumper in and the engine noise changes, then the tps is in the right sport at that moment for checking the base timing. IF you don't hear the change, then the tps is not reading idle and you get that revving situation you are describing above.
I suspect your base timing is not at 10 degrees, and is worth a check at this point.
The ecu runs the engine off the crank sensor in the distributor, which is adjustable and should be set at 10 whenever it is out for a timing belt or head change etc..
Your ecu detects misfires using the crank sensor on the crank and a timing gear which is not adjustable and is fixed. So maybe there is a discrepancy going on there.
I just saw a post on FB where the crank timing gear had broken teeth on it, it is possible your gear chipped off a tooth and will always read misfires but yours don't look like a solid enough pattern for that, not really sure.
When you have a misfire, the combustion generally doesn't happen, and the gas and o2 goes into the exhaust unburnt.
The o2 sensor then picks up the o2, and think you are running lean cause of all the unburnt o2, and this is called a "false lean" reading.
The ecu then goes ahead and give you more fuel which is why your fuel trims are spiking, and could also be why there is so much carbon buildup on the pistons.
At this point it would just be guesses without taking everything apart. The software can tell you all that info but it doesn't narrow down if it is the cause or a symptom of something else going on.
So start with the basics, check the injector clips on 1 and 6, check the ignition components, verify that the base timing is correct, basically eliminate one by one.
To check the crank gear the crank pulley needs to come off which is removing a lot of parts, so rule out all the stuff you can reach first.
I just checked the timing with an Innova digital gun.
Car was warmed up for about 10 mins, then raced at 2500RPM for 90s and returned to 700RPM.
I connected TE1-E1 and put the light on the pulley. Saw 10 degrees on the white line. When I unplugged TE1-E1 I saw approximately 15 degrees estimating. When I set the gun to 10 degrees, the white line was on 0.
Here's a picture of the flash as best I could get. Also it sounds to me like there's a valve ticking very loud that ticks very loud then is quiet, then loud then quiet etc.
OK I spent a couple hours looking at more things - maybe bad news.
-Triple checked TPS (for the 500th time)
-I am now very aware of a whooshing sound when blipping the TB
-While stopping/starting the car testing things, one time it started making this horrible spinning/grinding noise from the head area - I stopped it the car and it kept spinning as whatever it was slowly wound down. I started it again and it was back to normal.
I started looking in the back by 5 & 6 for anything and could hear a faint whistling sound. I was somewhat confident this was coming from inside the brake booster . Is it normal? The hoses and check valve are good, no leaks. Reminder: the brake pedal becomes hard as a rock over night.
From then I started squeezing around the hoses near the P Q R valve and could hear something but I wasn't 100% sure from where.
THEN I blipped the TB and heard a very distinct whooshing sound which I thought was coming from the PCV hose to the TB. In this video you can see the hose visibly deforms when I open the TB. I don't think it was this hose though - keep reading.
I took off the hose thinking maybe it had a leak but it held vacuum and stopped the car to put a different one on. I might replace it anyway since it's deforming from air(?)
This is when I started it and the engine sounded horrible like I've never heard before, like a metallic high pitched noise - compare how it sounded in the prior video to how it sounded when this **** happened- I shut the car off and heard this winding down sound. I don't know what the hell this was but it did not sound good. Lots of wind noise sorry.
I started it up again and it went away?? Then I took off the rear plug cover and tried diagnose the whooshing sound further. I don't think it's the hose and think it's coming from the top of the head somewhere - could it be a stuck intake valve or a broken valve?
This is after I restarted it after that horrible sound and trying to find that whooshing air noise.
Also just to log the data because I did it here's the OB2 readings in Gsheets and I didn't get a screenshot but the usual P0301 and P0306 and P300 codes show in the scanner but there's no MIL/CEL
Only 2 thath ave a slight abnormal reading are the injector response time (by 0.1ms) and IAC stepping - but the scanner reads duplicate PIDs for these so who knows?
This was an overnight cold start and idle for about 15mins - no driving.
Crap, this is just getting worse. I took it out to go to the grocery store and got a in memory code from the scanner for "P0116 Engine Coolant Temperature Circuit Range/Performance Problem"
The p0116 code went away at the grocery store.
On the way back I get to a stoplight and held the engine to about 2300 to see if I could hear anything and the misfire count went crazy to 200+ and the CEL light came on.
Today I replaced the ECT sensor since I got that code which may be nothing who knows, but it's replaced with an Autozone one (hope it's not crap - probably will be)
And
I pulled out the ECU to check the caps.
I know visual inspection doens't tell all, but they look OK to me. No leaks, no swelling.
Additional update - ECT sensor code gone and now the engine temperature gauge is right on the lower halfway mark - I had seen recently that the car seemed unusually cold as the gauge was at the bottom mark or the 2nd one.
Confirmed there's some sort of whistling air sound near the brake booster.
Now here's something interesting - I can make the engine misfire consistently by revving in neutral between 2000-3000 - in that range the misfire count just goes bonkers. But accelerating and driving in that range doesn't do that- i just see a couple pop up like 2-10. normal acceleration
Now sitting in neutral and revving to 2000-2500 - I let off so I wouldn't trigger CEL
I think youve gotten ahead of yourself. remember KISS keep it simple stupid. We know 1 and 6 are the problem lets check for spark and one and six. Move the spark plugs if your getting spark to 2 and 5 and see if the misfire follows the plugs. If you have the distributor check the resistance of the wires and u can even move the wires but they have to also be moved accordingly on the distributor
Next check for fuel, You can listen to the injector pulsing with a stethoscope or see it with a noid light. you can always move them as well and see if the misfire moves
IF these check out good were moving on the Compression tests first then Leakdown tests.
edit did NOT resolve the problem but fixed a loose wire - I hooked up a plug light tester and noticed spark light was inconsistent. See video below - the soldering of the wire did not fix the problem however.
A long time ago when I had a 2step ignition I had used simple plastic wire ends to splice the 12v signal from the engine to the coil pos/neg. I plugged in a multimeter to the harness side and was NOT getting 12v to the coil connector them I moved the wires and I got 12v. Tested this with 2 multimeters to verify. the postiive side cable was loose in the conenctor so I just soldered it in.
Could this cause the coil to burn up? My MSD D6 had to be sent in for repairs cus it burnt out and when I got it back it burnt out again in a few months. I put the stock one back in and just thought it was defective after having it repaired and never looked back. The primary coil resistances may be out of spec again on the new NGK one as well - but I saw a post on a toyota forum that most meters are not sensitive enough for the primary coil readings.
Primary coil was like 0.02 and secondary was 9. I forgot the decimal places so this may be useless info.
today I checked the distributor (put engine at TDC and lined up rotor to #1) - no leaks - no cracks that I can see from outside. there's a nick on part of the plastic on the inside of the dizzy?
there's a piece of plastic chipped off at the top don't know if that's something
03-25-21, 10:59 AM
