92ehatch

I don't have the new leads installed except for the one from ignitor to distributor. I did install the others as a test one day but it didn't help. They fit so loose that i took them back off. I still can't rule them out since those were so poor.

brand new battery and alternator, voltage is good. Grounds are good as well amd my ignitor passes the resistance test in the fsm.

I'll check that my spark is solid and that i don't have any voltage leaks and report back. There are alot of things i have tried already.

i have all new coolant sensors, new csi time switch, new denso 02 sensor. Tried two different afms. Checked wire resistance from all sensors to ecu. Back probed ecu and verified voltages from sensors were correct. Mechanical and ignition timing set properly, no vacuum leaks, vacuum lines installed correctly, egr blocked off/removed, dash pot removed, cold idle valve cleaned and calibrated.

I have not verified solid spark
fuel pressure
i have 4 new injectors (4 hole, were titled as bosch but i can't confirm this ebay transaction)

Melrose 4r

yes no problems at all and knocking down 20-21 mpg on highway runs. just uses some oil.

Melrose 4r

Do you know anyone with a hand held air/fuel meter? It would be a good thing diagnostically if you could see whats going on while its running poorly, too lean or rich. Must be lean.

i've reread your problem description and it sounds like if it was a carbed engine it would be going lean as the throttle opens which would be accelerator pump or enrichment ckt. So i guess the comparable system on the EFI is the TPS.
could it have a dead spot electrically at part throttle?

92ehatch

I have a video in my build thread i may be able to link here. It shows the hard start that only occurs with a cold engine and hot ambient temp. It also allows you to hear the stumble when i give it throttle. The hard start is non existent when is cold outside, fires right up. The stumble doesn't care what temp it is.

the cold start injector is working properly, the timer also works (it's new) tested all electrical circuits with my fluke 87v. I did not do a voltage check on the tps while moving the throttle because, well my arms aren't that long.


and how it acts when i unplug the cold start injector
I have not yet verified if unplugging the csi helps when it is cold

Thommo Thompson

right, before u go on, put those new loose fitting leads on and also make sure the spark gap is correct. i personally have resolved this exact issue on a suzuki engine where we were unable to get new leads and had to make the broken leads work. the symptoms were exactly as u describe. the solution was to isolate each plug lead away from all metal earth points and to bang the spark plug gaps back to exactly tight original spec. too big a gap, OLD leaking HT leads and a slightly weak coil just cant jump it with the rich mixture at cranking rpm and missfires when accelerating.
u sure u measure the voltage at the coil positive with the coil energized at idle.
without it energized and running the engine it wont be loading up the wires with current required to test the wires. Im sure you already know this as u pointed out u are very competent with electrics.

Thommo Thompson

oh and undo ur engine to chassie earth straps and clean them. a good voltage at the coil is hopeless if it cant get from the enging back to the battery negative!!!
mine corrodes ever 2 months hhah and i gotta undo it and clean the stuoid thing

Co_94_PU

iTrader: (-1)

You have something going on with the ground strap to the intake, or cluster, the first video shows the temp gauge dropping out. This has effect on all the sensors over there as well as the ECU and injector banks.

Problem #1, endless cranking. Does cracking the throttle plate, pushing gas pedal have any positive effects?

Theory, too much fuel not enough oxygen.

Problem #2, throttle lag. When was the timing chain inspected? Was the tensioner replaced? Can you put an analog gauge on the oil pressure? Are you running "per specification" oil?

​With the chain tensioner being mostly oil pressure dependant there is going to be a bit of lag. It shouldn't really have any effect on cam timing , it is on the slack side of the chain, but if it has a weak link it could stretch on the powered side I guess.

You can tap the throttle and AFM signals from inside the cab at the ECU by back probing the plugs (probe inserted from the back side of the ECU plug) as I did when I initially set my tps in my thread.


The vafm signal could lag because of vacuum "leaks", abit from spring pressure, and also congestion of the idle by pass ( hidden under the plug ) or air filter.

92ehatch

the gauge fluctuation is the gauge itself, i can disassemble it, then tighten everything and it will work for a little while and then start doing it again.

i replaced and cleaned the ground to the motor mount/intake brace and the rear of the head to the chassis, as well as the ground from the power steering to the chassis.

timing chain is all new (just rebuilt everything) i also already back probed the ecu, twice, and everything checks out.

I'm going to look into the ignition system today as suggested, my other thoughts are tps or the ebay purchased fuel injectors (they are supposedly bosch 4 hole but they came in as some grey plastic things that i felt were not what they were labeled as)

I can not test the long crank problem until summer since it's not hot enough to have that problem, then when it is hot enough once it starts i have to wait hours for it to do it again

Co_94_PU

iTrader: (-1)

You said you couldn't/didn't check the TPS because "arm to short". If you monitor the signal at the ECU you will see if it's in range and not dropping out while running or manipulating the throttle.


Tps voltage test at ECU.

92ehatch

I had engine off with my child holding the leads to the back of the ecu pins and reading out as i manipulated the throttle and he would call out the readings. For some reason i don't remember why i had to have him hold them in. Maybe in the summer sun i want thinking to sit in the drivers seat, maybe i had the throttle cable off... who knows. I'll recheck that reading now. Even though my fluke is at work ands my home meter is a piece of. .. slow with no manual range so if it changes range it shows o.l. for a moment which is not good for testing.

i did check spark at the plugs, nice bright spark, blue, not orange. Voltage to ignitor is 11.78 volts with battery at 12.05. Voltage to ignitor plus and battery negative is also 11.78. Air gap in distributor is correct. Primary and secondary resistance is correct, pickup coil resistance is correct.

92ehatch

Correction, i never did the voltage tests at the ecu for the tps, only resistance tests.

test was done with engine off, battery voltage 12.05

i just did them. Still had to hold my leads in the ecu while someone else moved the throttle

idl to e2 throttle open 11.5v
vcc to e2 4.98
vta to e2 throttle closed .35
vta to e2 throttle open 3.64

the last one showing wide open throttle vta to e2 is under spec of 4 to 5volts. It does read fluid from closed to open with my cheap meter going o.l for a moment when it changes from 1.9xx volts to 2.xx volts. This of course being a range change in my meter.

so if .4 volts on my tps is enough to cause this whole problem I'll change it, but something tells me it's not.

92ehatch

I went through the fsm and checked voltages at all the efi system pins, injectors, vafm, temp sensors. They all check out.

92ehatch

I buttoned everything back up and started the truck and rechecked all voltages at the ecu for everything. Afm, tps, etc. Basically went Down the list on the fsm. All values are in spec except for the wot on tps is still only 3.64.

some values did come up due to the alternator running, so the ones that we're 11.xx came up to 13.xx with alternator voltage.

the only difference i noticed this time, i had the air filter out and could hear a backfire into the intake when it misfires on acceleration.

i tried advancing and retarding the ignition timing with no effect on the miss fire, only idle and throttle response were affected by these changes.

i sprayed all the ht wires and igniter with water and do not see any arcs coming from the wires. Spark plugs are gapped to .8mm as specified.

i think I'm going to replace the tps and take those fuel injectors out and replace them with the factory originals and verify that my rewired pig tails for my injectors are ok and i didn't screw something up there.

Thommo Thompson

jees, theres a lot of variables here.
cam out by 2 degrees, new injectors, and getting backfiring out intake. intake backfires are usually indicative of a lean condition.
is exhaust blocked?
haha. if the issues only started after the rebuild then it must be those injectors.

92ehatch

It ran fairly poor prior to the rebuild. Had trouble idling, very noisy, hard start condition. All the parts i changed tested bad.

the exhaust seems to flow fine, the cat was replaced at some point because it was stolen but i can't remember when that was done, way prior to me getting the truck. It was welded in so i can't look at it without cutting.

csi time switch was bad, ect was bad, gauge coolant sensor was bad, o2 sensor was bad, timing guides were bad, ignitor wire corroded at dizzy cap which cracked the cap. That's why i went though the rebuild.

i checked the number on the side of the injector, it cross references to a motocraft (ford) injector which does seem to be bosch made with everything i have found so far. They ohm out at around 14 or so. I have the resistor box removed.

i think i will change the tps, as i said it's the original and i opened it to rewind the spring because it wouldn't return properly to the idl spot. Even though it is working as of now i think it couldn't hurt.

i also think I'll order a fuel pressure Guage as that is the only system i haven't checked. At this point, i have spark, compression, timing, fuel is all that's left. If the fuel pressure checks ok,and the tps doesn't fix it then I'll remove the upper plenum and recheck my injector wiring and reinstall the factory injectors (after bench testing them off course)

92ehatch

Number from the side of the injector is xs4u-ab

all i can find is a flow rate of 182cc from an eBay listing for similar injectors. I'm pretty sure the 22re uses a 190cc injector so I'm not sure how 8cc would affect it.

92ehatch

Took a short video of the exhaust at the misfire. Black smoke indicating rich mixture.

Thommo Thompson

i just lost my long reply. im not typing it again.
I typed it out then my 8nternet dropped out before i hit send which causes the page to dropout and long typed out message goes into the abyss.
very angry.
im short, i said u cant see the amoke in the video, the smoke can be black from weak spark, EFI low rpm bogging is less likely fuel and more likely spark, because efi electric pump is constant, and edi fuel pressure regulator is based on engine vacuum (engine load)
bugger it i cant get the point across without all the intricate details.
can u just trust me and look further into the spark.

92ehatch

I'll do this. I need a new oem set of ignition wires anyway. I'll go ahead and order those in. I think in tossed the other set from o Reillys , couldn't find them.

I'll make a ground strap from my ignitor directly to the engine, which has 3 brand new grounds attached to it. This will ensure that my ignitor is grounded and the wires are new. The distributor cap and rotor are brand new toyota so those should be good. I think after that it will either fix it or eliminate spark as a possibility. Hell, after i checked it the other day i went and checked it again later. But those are unloaded tests.

i also have to say i didn't think it was fuel pressure related either which is why i haven't touched that part of the system, and why I've been checking other parts. I am starting to run out of ideas and testing that system couldn't hurt. I've always thought it was an electrical issue, which of course can be the hardest to track some times. I worked all sumer at it, then let it sit , now i'm back at it.

Thommo Thompson

haha yes, spark tests are difficult. for us diyers, sometimes the only way to really test things is to buy new parts and try it. ignition is one of those things.