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Messages - Masejoer

Engine Tech / Re: Troubleshooting persistent misfire
Make sure you don't have the LH and RH oxygen sensor connectors swapped. I did this inadvertently when installing the 5.0L engine in my car and I fought a rough idle and random cylinder lean condition for a few months before I figured it out.  The car would run great in open loop, but when it warmed up and went into closed loop it would run like crap, because it was leaning out the wrong side of cylinder banks.  It's an easy mistake because LH and RH connectors are keyed the same, yay Ford  :beatyoass:

I don't. I did some decade ago and found that the ecu would start to richen up one bank (thinking it was lean), and lean out the other (thinking it was rich). Eventually it'd fail out of closed loop and go open again. These computers really aren't the smartest in terms of things like this, or having functions that don't always have increasing values (computer flat out fails and stalls the engine), but they work.

The o2 sensor thing is really obvious in tuning software! I wish my issue was a simple as that  :frown:
Engine Tech / Re: Troubleshooting persistent misfire
I should be able to oscope some things this weekend, after trying to install some sn95 mustang seat frames with new 03/04 cobra foam and upholstery. Goodbye leaning driver seat!

Also have my new, longer 1/0 power wire here to re-do my current alternator cable for a cleaner install, and using non-set-screw terminals. Lots of time sinks planned for this weekend! Will also look into where I'd like to weld in some thick grounding bars. Been planning on cleaning up all the electrical connections, wire looming, and techflex sheathing for a long time. Been sitting on parts since summer 2012...
Engine Tech / Re: Troubleshooting persistent misfire
It sounds like metal hitting something. The exhaust isn't touching anything is it?

If it's not that you could try disabling one cylinder at a time on the bank to see if the noise goes away. At least you would be able to pin point the noise that way.

Yeah, this side is the one where the exhaust is right up against the transmission pan's lip. The 4r70w bellhousing is larger than the aod, so clearances on pre-fabbed exhaust pipes are lacking.
Electrical Tech / Re: Engine bay connector near coil
There are EVTMs linked in @TheFoeYouKnow  's sig.


Give it a look.

I've been through many areas of the EVTM looking for the red/yellow black/white 2-pin connector. The connector has round pins and very red (not pink), so it doesn't seem to have anything to do with the washer fluid reservoir. Most everything else in the EVTM has nothing to do with that part of the vehicle. I expected washer fluid or something with cruise control.

Maybe just the "washer pump test connector"? EVTM doesn't show any red wire though.
Engine Tech / Re: Troubleshooting persistent misfire
If I attach a stethoscope hose perpendicular to the side of my tail pipes, but blocking out open air, the exhaust drone is cut down, but I hear an occasional faint sound like this from the passenger side:

Higher tone, sort of a 'tapping on a shot-glass' sound when using the stethoscope.

Nothing on the driver side pipe.

My mid pipe does need to be re-created though (BBK pre-made). It's right up against the transmission pan lip.

Best recording I can get - pushed one of my calibration mics into a hose: LINKED MP3

The recording (1KHz 6dB high pass filter applied, gain applied) is different than to the ear, but this sure sounds like pinging.
Electrical Tech / Engine bay connector near coil
I've never known where this goes to - does anyone know? Located coming out of the harness near the ignition coil. It has two of the four wires that go into a larger black connector, which has 4 total pins.

Engine Tech / Re: Troubleshooting persistent misfire
The ones I remember looked like this but I bet you can do it with a regular scope too.  I'm not an electrical type person so never learn how.  Sorry.

Oscilloscopes are great - Voltage over time, with an adjustable time-scale. Just an extension of a point-in-time Voltmeter.
Engine Tech / Re: Troubleshooting persistent misfire
I have a couple portable 2-channel oscopes (20 and 60MHz), and a benchtop 100MHz 4-channel. Just need to see what type of signals I can probe at, from where, and have an idea of what I'm looking for on the ignition side. I don't normally scope beyond microcontroller work, and low Voltage vehicle signals.
Engine Tech / Re: Troubleshooting persistent misfire
Is that like an inductive setup? I'd imagine something could be put together, or a timing light hacked up, that would work to read from an oscope. I may put together something this weekend.

I forgot that I shipped my Quarterhorse off to Moates to get the updated revision. I won't be able to get datalogs for a couple weeks until I receive the replacement unit back.
Engine Tech / Re: Troubleshooting persistent misfire
No, I don't do anything with other local 'car people', as most are usually less about vehicle engineering, and more about "mods" to vehicles that often hinder performance, and they don't understand how. Not my type of crowd. A typical truck forum shows the demographic I'm talking about, where these types seem to run rampant.

I'd be curious about a coil, but I've gone down the route of "throw parts and time at it" before with various things. No sense in buying new parts if Ill be changing it up.

Anyone have a stock crankshaft pulley for not-$50? Need to get one for trigger wheel install.
Engine Tech / Re: Troubleshooting persistent misfire
You still have the old stock coil? Check there first. Mine was behaving similarly when the MSD coil on the car crapped out.

Put a stock replacement Motorcraft coil on and it's been fine since.

I thought your issue was a cracked spark plug?

It has a coil that has seemed to work (it may have been replaced 20,000 miles ago, but who knows at this point. A decade ago), but the coil is a part that I didn't have luck replacing a few years back. Rather than get a entirely new coil at what is likely $80-100, I'd prefer to get this EDIS-8 conversion underway.

I was tempted to tap into an inductive sensor and datalog the coil pulses via the dataq, so that I also have that data available to review. I'd really not care if the EDIS conversion simply fixed my issue though.

Edit: Coil from LMR is $60 shipped
Engine Tech / Re: Troubleshooting persistent misfire
What's your tps set to at CT KOEO? When you replaced the IAC and TPS how did you reset base idle just out of curiosity. Also can you share the datalog .CSV file for binary editor? For when its acting up obviously.

Binary Editor is reading 0.97V at idle.

Let me fire up the new BE version on my replacement laptop and get some newer datalogs (old laptop has BE2010), and I'll get a new cold to warm garage-idle datalog posted.
Engine Tech / Re: Troubleshooting persistent misfire
What I've done/re-tested lately:

- Smoke machine intake test, no leaks with oil filler cap taped down
- Distributor swapped out with a new unit, new TFI, as a test. No change. Caps/rotors still both look new.
- New BAP, TPS, air charge, engine temp sensors
- New IAC
- IAC block off
- Rocker arms checked to ensure preload
- EGR valve tested
- Cleaning of TFI plug
- Cleaned and increased contact tension of the salt and pepper connectors at engine harness
- New battery
- Shaken/wiggling harness connections when running to look for change in idle quality (none)
- 30lb EV6 Injectors flow tested - good.
- Reinstalled some original refurb/flow tested 19lb EV1 injectors to test stock tune.
- MAF seems to sweep fine, but reinstalled stock 1989 MAF to test stock tune.
- Leakdown test shows 8-10% across all cylinders. No sound from intake or exhaust - crankcase only. PHOTO PHOTO
- 165-170psi compression test across all cylinders
- plugged off vacuum lines an pcv, no vacuum at oil filler tube (lower intake gaskets should be good). Slight vacuum at oil filler tube with pcv re-attached.
- no exhaust smoke
- no coolant or oil issues
- stock tune (minus increasing CID to 306, and disabling thermactor) with stock injectors and MAF
- new engine bay grounds with conductive grease
- cleaned and re-mounted eec-iv computer grounds
- timing at 10 degrees base. According to tuning software, issue still exists at all timing so not a timing advance issue
- timing should be correct on balancer - markings seem to match TDC of various cylinders perfectly (for leakdown test). Timing chain doesn't appear to be off.
- no engine running codes. Cylinder balance test comes back as passing
- engine is idling fine at 650-750rpms, around the 672 being commanded. Should be more steady.
- 16in/Hg vacuum at warm idle with all vacuum accessories attached, 1300rpm and above get 20in/Hg
- Coolant temperature is a steady 206-208F at temperature sensor when idling or driving, 160F intake runner temperature at idle in garage
- I've tried completely isolating plug wires into air as a test, but no change
- Spark plugs all look great PHOTO
- Correct firing order PHOTO
- Timing light on each wire doesn't appear to have any missing ignitions. I hoped to find one with occasional missing flashes...
- Replaced capacitors in A9P
- Binary Editor datalogs generally look good - the stumble isn't timing swinging around.
- Idle doesn't improve if I richen up the AFR. Leaner than stoich just starts to stumble, as expected.
- Fuel pressure 40psi without vacuum, 33psi at idle with vacuum. PHOTO PHOTO
- New alternator due to failing bearings. New alternator's AC ripple is 29mA.
- EGR block off

Things that I still want to check:
- Replace salt/pepper engine harness connectors with 12-pin deutsch connectors
- New coil again? Years ago I tried a new aftermarket coil, but it would breakup badly at 2500+ rpms. I went back to my old coil.
- Unplug Quarterhorse completely and run stock tune only with stock MAF/injectors
- Exhaust smoke machine test
- Try a completely different A9P?

Other plans:
- EDIS-8 to ditch TFI altogether. Just need a crank pulley to take to machine shop with trigger wheel for welding/balancing
- Install my Lightning MAF, for potential better metering than the aftermarket unit, unrelated to stock air/fuel parts and tune
- Upgrade from 130A alternator to newer 200A, 0awg ground upgrade
- Maybe removing the exhaust to see if my issue has nothing to do with the motor, but ignition in the cats sending waves back up to the motor, messing with cylinder activity?
- New seal on oil filler lid since I get a slight leak under pressure from the smoke machine
Engine Tech / Re: Troubleshooting persistent misfire
My powertrain specifications:

Stock-type 306 rebuild from 15 years ago, 20k miles on the rotating assembly:
TRW-L2305F30 pistons
SLP-E-251K030 rings
SCA-35090P i-beams
Stock 1989 Mustang camshaft
Stock pan, pump, crank machines and balanced with the rotating assembly
Powerbond 50oz SFI balancer
Timing setup dot to dot, and seems correct for TDC marks on balancer for each cylinder when I tried leakdown tests

Rest of engine (newer than shortblock):
TW 170cc heads cut down to 54cc chambers (lots of clearance with 1.7 rockers, clayed)
Comp-cams high energy hydraulic roller lifters set to 0.025 preload
Whatever pushrod length was needed when the heads were initially installed
GT40 tubular intake with lower porrted by tmoss
19lb stock injectors, and 30lb FMS injectors
Stock MAF, and PMAS 75mm "24lb" MAF
Accufab 70mm throttle body
FMS stainless "gt40p compatible" shorty headers with 1-5/8" primaries
Autolite 3924 plugs gaps tested at .040 and.050
MSD spark wires, <100 miles
Stock distributor/TFI, and Richporter FD04 replacement
Standard "195" thermostat
New Motorcraft TPS
New Motorcraft air charge and engine temp sensors
Various gaskets, 9.8:1 static compression ratio.
EGR and IAC still installed
Currently have fresh 92 octane ethanol-free fuel

4R70w transmission/stock VB/clutches from 2003 3.8L
Larger capacity trains oil pan with cooling fins
PI Stallion 3000 stall converter
Stock driveshaft
8.8" rear differential with 3.55 gears, 26.6" wheel diameter

1989 A9P ECU with new capacitors
Quarterhorse tuning board
New Motorcraft fuel regulator
2.5" exhaust, catalytic converters intact (few hundred miles)
Larger, soldered engine grounds with contact areas using NO-OX grease
Dual Innovate LC-2 wideband sensors mounted horizontally near bottom of exhaust down-pipes
DataQ datalogger  for widebands
Young narrowband o2s that sweep well
1/0 gauge alternator power wire, 4awg timing cover to battery ground, 7awg dual braided head to firewall grounds, crimped and soldered terminals

Much of the above hasn't seen more than around 100 miles in over 5 years. A week ago it was driven to a glass shop, and likely doubled the mileage it has seen since being driven to a new house years ago.